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  <front>
    <journal-meta>
      <journal-id journal-id-type="publisher-id">abcic</journal-id>
      <journal-title-group>
        <journal-title>ABC Imagem Cardiovascular</journal-title>
        <abbrev-journal-title abbrev-type="publisher">ABC Imagem Cardiovasc.</abbrev-journal-title>
      </journal-title-group>
      <issn pub-type="ppub">2318-8219</issn>
      <issn pub-type="epub">2675-312X</issn>
      <publisher>
        <publisher-name>Departamento de Imagem Cardiovascular da Sociedade Brasileira de Cardiolodia (DIC/SBC)</publisher-name>
      </publisher>
    </journal-meta>
    <article-meta>
      <article-id specific-use="scielo-v3" pub-id-type="publisher-id">VMHGNLDwVpYDWXsCdrbwNWs</article-id>
      <article-id specific-use="scielo-v2" pub-id-type="publisher-id">S2675-312X2026000300601</article-id>
      <article-id pub-id-type="other">00601</article-id>
      <article-id pub-id-type="doi">10.36660/abcimg.20260059i</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Original Article</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Correlating Invasive and Echocardiographic Hemodynamic Measures in Patients with Heart Failure with Reduced Ejection Fraction</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0002-1568-5124</contrib-id>
          <name>
            <surname>Barbato</surname>
            <given-names>Jo&#227;o Pedro da Rosa</given-names>
          </name>
          <role>Conception and design of the research</role>
          <role>acquisition of data</role>
          <role>analysis and interpretation of the data</role>
          <role>statistical analysis</role>
          <role>obtaining financing</role>
          <role>writing of the manuscript</role>
          <role>critical revision of the manuscript for intellectual content</role>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
          <xref ref-type="corresp" rid="c1"/>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0003-2150-6337</contrib-id>
          <name>
            <surname>Scolari</surname>
            <given-names>Fernando Luis</given-names>
          </name>
          <role>Conception and design of the research</role>
          <role>analysis and interpretation of the data</role>
          <role>statistical analysis</role>
          <role>writing of the manuscript</role>
          <role>critical revision of the manuscript for intellectual content</role>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0002-5514-2562</contrib-id>
          <name>
            <surname>Machado</surname>
            <given-names>Guilherme Pinheiro</given-names>
          </name>
          <role>analysis and interpretation of the data</role>
          <role>statistical analysis</role>
          <role>critical revision of the manuscript for intellectual content</role>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0009-0001-7116-6193</contrib-id>
          <name>
            <surname>Amon</surname>
            <given-names>Andr&#233; Barcellos</given-names>
          </name>
          <role>acquisition of data</role>
          <role>analysis and interpretation of the data</role>
          <role>critical revision of the manuscript for intellectual content</role>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0003-2402-2565</contrib-id>
          <name>
            <surname>Crivelaro</surname>
            <given-names>Pedro Castilhos de Freitas</given-names>
          </name>
          <role>acquisition of data</role>
          <role>critical revision of the manuscript for intellectual content</role>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0001-8289-7357</contrib-id>
          <name>
            <surname>Menegazzo</surname>
            <given-names>Willian R.</given-names>
          </name>
          <role>Conception and design of the research</role>
          <role>acquisition of data</role>
          <role>analysis and interpretation of the data</role>
          <role>critical revision of the manuscript for intellectual content</role>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0009-0002-5671-1453</contrib-id>
          <name>
            <surname>Berger</surname>
            <given-names>Solano Vinicius</given-names>
          </name>
          <role>Conception and design of the research</role>
          <role>acquisition of data</role>
          <role>analysis and interpretation of the data</role>
          <role>critical revision of the manuscript for intellectual content</role>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0002-1989-1670</contrib-id>
          <name>
            <surname>Araujo</surname>
            <given-names>Gustavo Neves de</given-names>
          </name>
          <role>Conception and design of the research</role>
          <role>analysis and interpretation of the data</role>
          <role>statistical analysis</role>
          <role>writing of the manuscript</role>
          <role>critical revision of the manuscript for intellectual content</role>
          <xref ref-type="aff" rid="aff2">
            <sup>2</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0001-7102-6644</contrib-id>
          <name>
            <surname>Valle</surname>
            <given-names>Felipe Homem</given-names>
          </name>
          <role>Conception and design of the research</role>
          <role>analysis and interpretation of the data</role>
          <role>writing of the manuscript</role>
          <role>critical revision of the manuscript for intellectual content</role>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0001-7596-2827</contrib-id>
          <name>
            <surname>Wainstein</surname>
            <given-names>Rodrigo Vugman</given-names>
          </name>
          <role>Conception and design of the research</role>
          <role>analysis and interpretation of the data</role>
          <role>writing of the manuscript</role>
          <role>critical revision of the manuscript for intellectual content</role>
          <xref ref-type="aff" rid="aff1">
            <sup>1</sup>
          </xref>
        </contrib>
        <aff id="aff1">
          <label>1</label>
          <institution content-type="orgname">Hospital de Cl&#237;nicas de Porto Alegre</institution>
          <addr-line>
            <named-content content-type="city">Porto Alegre</named-content>
            <named-content content-type="state">RS</named-content>
          </addr-line>
          <country country="BR">Brazil</country>
          <institution content-type="original">Hospital de Cl&#237;nicas de Porto Alegre, Porto Alegre, RS &#8211; Brazil</institution>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution content-type="orgname">Hospital da Unimed Grande Florian&#243;polis</institution>
          <addr-line>
            <named-content content-type="city">Florian&#243;polis</named-content>
            <named-content content-type="state">RS</named-content>
          </addr-line>
          <country country="BR">Brazil</country>
          <institution content-type="original">Hospital da Unimed Grande Florian&#243;polis, Florian&#243;polis, RS &#8211; Brazil</institution>
        </aff>
      </contrib-group>
      <author-notes>
        <corresp id="c1"><label>Maling Address:</label><bold>Jo&#227;o Pedro da Rosa da Rosa Barbato</bold> &#8226; Hospital de Cl&#237;nicas de Porto Alegre. Rua Ramiro Barcelos, 2350. Postal code: <postal-code>90410-000</postal-code>. Porto Alegre, RS &#8211; Brazil E-mail: <email>jpdarosa94@gmail.com</email> </corresp>
        <fn fn-type="coi-statement">
          <label>Potential Conflict of Interest</label>
          <p>No potential conflict of interest relevant to this article was reported.</p>
        </fn>
        <fn fn-type="edited-by">
          <label>Editor responsible for the review:</label>
          <p>Marcelo Tavares</p>
        </fn>
      </author-notes>
      <pub-date date-type="pub" publication-format="electronic">
        <day>03</day>
        <month>09</month>
        <year>2026</year>
      </pub-date>
      <pub-date date-type="collection" publication-format="electronic">
        <year>2026</year>
      </pub-date>
      <volume>39</volume>
      <issue>3</issue>
      <elocation-id>e20260059</elocation-id>
      <history>
        <date date-type="received">
          <day>29</day>
          <month>04</month>
          <year>2026</year>
        </date>
        <date date-type="rev-recd">
          <day>28</day>
          <month>06</month>
          <year>2026</year>
        </date>
        <date date-type="accepted">
          <day>13</day>
          <month>07</month>
          <year>2026</year>
        </date>
      </history>
      <permissions>
        <license license-type="open-access" xlink:href="https://creativecommons.org/licenses/by/4.0/" xml:lang="en">
          <license-p>This is an open-access article distributed under the terms of the Creative Commons Attribution License</license-p>
        </license>
      </permissions>
      <abstract>
        <title>Abstract</title>
        <sec>
          <title>Background:</title>
          <p>The management of heart failure with reduced ejection fraction (HFrEF) has advanced with the use of invasive hemodynamic markers such as cardiac power output (CPO) and pulmonary artery pulsatility index (PAPI). Simultaneously, interest has grown in noninvasive prognostic indicators, especially the left ventricular outflow tract velocity&#8211;time integral (LVOT-VTI).</p>
        </sec>
        <sec>
          <title>Objective:</title>
          <p>This study aimed to assess the correlation between invasive and echocardiographic parameters, particularly CPO, PAPI, and LVOT-VTI, in patients with HFrEF.</p>
        </sec>
        <sec>
          <title>Methods:</title>
          <p>This cross-sectional, single-center study included inpatients and outpatients with chronic stable or acutely decompensated HFrEF. Individuals with cardiogenic shock (CS) were excluded. Right heart catheterization (RHC) and echocardiography were performed on the same day. Statistical significance was defined as a two-sided p value &lt; 0.05.</p>
        </sec>
        <sec>
          <title>Results:</title>
          <p>Significant correlations were observed between invasive and echocardiographic CPO (r = 0.737, p &lt; 0.001) and PAPI (r = 0.604, p &lt; 0.05). LVOT-VTI showed significant correlation with CPO measured via pulmonary artery catheter (PAC) (r = 0.469, p &lt; 0.01). Echocardiographic PAPI was measurable in only 16 patients. A sensitivity analysis of those receiving inotropes showed an even stronger correlation between invasive and echocardiographic CPO (r = 0.812, p = 0.005).</p>
        </sec>
        <sec>
          <title>Conclusion:</title>
          <p>Echocardiographic and invasive hemodynamic parameters showed significant correlations in HFrEF, particularly CPO, supporting echocardiography as a potential alternative for hemodynamic assessment. However, the low feasibility of noninvasive PAPI measurement highlights important limitations in this population.</p>
        </sec>
      </abstract>
      <kwd-group xml:lang="en">
        <title>Keywords:</title>
        <kwd>Systolic Heart Failure</kwd>
        <kwd>Hemodynamic Monitoring</kwd>
        <kwd>Heart Rate</kwd>
        <kwd>Echocardiography</kwd>
      </kwd-group>
      <funding-group>
        <funding-statement><bold>Sources of Funding</bold> This study was funded by the Fundo de Incentivo &#224; Pesquisa (FIPE).</funding-statement>
      </funding-group>
      <counts>
        <fig-count count="8"/>
        <table-count count="10"/>
        <equation-count count="0"/>
        <ref-count count="20"/>
      </counts>
    </article-meta>
  </front>
  <body>
    <sec sec-type="intro">
      <title>Introduction</title>
      <p>Heart failure (HF) is a growing global health issue, affecting an estimated 60 million people worldwide. Advancements in cardiac care and improved patient survival have contributed to the rising prevalence of this syndrome.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> The use of pulmonary artery catheter (PAC) for hemodynamic assessment remains a cornerstone in HF management. These invasive measurements are essential for diagnosing and optimizing treatment strategies in both chronic and decompensated HF, providing insights into disease progression and therapeutic response.<sup><xref ref-type="bibr" rid="B2">2</xref>,<xref ref-type="bibr" rid="B3">3</xref></sup> PAC use has increased in recent years, guided by a systematic approach that prioritizes parameters with the greatest prognostic impact, such as cardiac power output (CPO) and pulmonary artery pulsatility index (PAPI). These hemodynamic parameters have become essential tools in determining the need for mechanical circulatory support in patients with cardiogenic shock (CS).<sup><xref ref-type="bibr" rid="B4">4</xref></sup> Although initially studied in CS, CPO and PAPI also have significant prognostic value in chronic and acutely decompensated heart failure with reduced ejection fraction (HFrEF).<sup><xref ref-type="bibr" rid="B5">5</xref>&#8211;<xref ref-type="bibr" rid="B7">7</xref></sup></p>
      <p>Research on noninvasive measures with prognostic value in patients with heart disease has also expanded, aiming to shorten evaluation time and improve safety. Among echocardiographic parameters, the left ventricular outflow tract velocity&#8211;time integral (LVOT-VTI) has demonstrated good prognostic value in observational studies.<sup><xref ref-type="bibr" rid="B8">8</xref>,<xref ref-type="bibr" rid="B9">9</xref></sup> The LVOT-VTI is a Doppler-derived echocardiographic measurement that quantifies the distance blood travels through the LVOT during systole, serving as a key parameter in assessing stroke volume, cardiac output (CO) and overall hemodynamic status.<sup><xref ref-type="bibr" rid="B10">10</xref>,<xref ref-type="bibr" rid="B11">11</xref></sup></p>
      <fig id="f4">
        <caption>
          <title>CPO: cardiac power output; e-PAPI: echocardiography-derived pulmonary artery pulsatility index; PAPI: pulmonary artery pulsatility index; LVOT-VTI: left ventricle outflow tract velocity time integral.</title>
        </caption>
        <graphic xlink:href="2675-312X-abcic-39-03-e20260059-0059i-gf01.tif"/></fig>
      <p>The correlation between invasive and noninvasive measurements in acute decompensated HF-related CS has been recently investigated, revealing associations between CPO and PAPI measured via PAC and echocardiography.<sup><xref ref-type="bibr" rid="B12">12</xref></sup> Similarly, the relationship between PAC-derived and echocardiographic parameters has been explored in patients with chronic HF;<sup><xref ref-type="bibr" rid="B13">13</xref>,<xref ref-type="bibr" rid="B14">14</xref></sup> however, these studies have not focused on parameters such as CPO, PAPI, and LVOT-VTI.</p>
      <p>Therefore, the objective of this study was to evaluate the correlation between invasive and noninvasive measurements in inpatients and outpatients with chronic stable or decompensated HFrEF, with particular emphasis on CPO, PAPI, and LVOT-VTI. The main findings of this study are summarized in the <xref ref-type="fig" rid="f4">Central Illustration</xref>.</p>
    </sec>
    <sec sec-type="methods">
      <title>Methods</title>
      <p>This is a single-center cross-sectional study conducted at a university hospital in the South Region of Brazil. Participants indicated for routine evaluation by the HF team were recruited by actively searching outpatient and inpatient lists. Recruitment occurred between May 2023 and June 2024, using phone calls and direct contact with hospitalized patients. All patients were invited to undergo echocardiography before or after right heart catheterization (RHC). The research protocol was approved by the institutional ethics committee, and written informed consent was obtained from all participants.</p>
      <p>The study included patients aged 18 years or older with a diagnosis of HFrEF (left ventricular ejection fraction &lt; 40%). Patients were excluded if there were technical difficulties in obtaining echocardiographic measurements or if RHC measurements could not be performed. Additionally, patients with CS, active infection, those on mechanical ventilation, or undergoing hemodialysis were excluded. Patients who received diuretics or vasodilators between the two evaluation methods were also excluded.</p>
      <p>The study protocol involved performing a comprehensive echocardiographic assessment by two experienced echocardiographers (SVB and WRM) within the shortest possible time before or after the invasive hemodynamic evaluation using a PAC. All evaluations occurred within a six-hour interval between the two examination methods.</p>
      <sec>
        <title>RHC</title>
        <p>The invasive hemodynamic evaluation was performed using RHC with PAC inserted via micropuncture technique of the right basilic vein or the right internal jugular vein. The zero-reference level was established at the mid-axillary line, and measurements were recorded at end-expiration. The operator performing RHC was blinded to the echocardiographic measurements.</p>
        <p>CO was assessed using the thermodilution technique. Central venous pressure (CVP), pulmonary pressures, and pulmonary artery occlusion pressure (PAOP) were determined as the mean values over eight cardiac cycles. CPO was calculated using mean arterial pressure (MAP) according to the formula: CPO = CO &#215; MAP / 451. The PAPI was calculated as: PAPI = PASP &#151; PADP / CVP, where PASP and PADP indicate pulmonary artery systolic pressure and pulmonary artery diastolic pressure, respectively. The remaining derived hemodynamic parameters were calculated using the formulas described in <xref ref-type="table" rid="t1">Table 1</xref>.</p>
        <table-wrap id="t1">
          <label>Table 1</label>
          <caption>
            <title>PAC-derived parameters</title>
          </caption>
          <table frame="hsides" rules="groups">
            <colgroup width="50%">
              <col/>
              <col/>
            </colgroup>
            <thead style="border-top: thin solid; border-bottom: thin solid; border-color: #000000">
              <tr style="background-color:#C58874">
                <th align="left" valign="middle">Parameter</th>
                <th align="center" valign="middle">Formula</th>
              </tr>
            </thead>
            <tbody style="border-bottom: thin solid; border-color: #000000">
              <tr>
                <td align="left" valign="middle">CPO</td>
                <td align="center" valign="middle">CO &#215; MAP / 451</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">PAPI</td>
                <td align="center" valign="middle">(PASP &#8722; PADP) / CVP</td>
              </tr>
              <tr>
                <td align="left" valign="middle">TPG</td>
                <td align="center" valign="middle">MPAP &#8722; PAOP</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">PVR</td>
                <td align="center" valign="middle">TPG / CO</td>
              </tr>
            </tbody>
          </table>
          <table-wrap-foot>
            <fn id="TFN1">
              <p>CO: cardiac output; CPO: cardiac power output; CVP: central venous pressure; MAP: mean arterial pressure; MPAP: mean pulmonary artery pressure; PADP: pulmonary artery diastolic pressure; PAOP: pulmonary artery occlusion pressure; PAPI: pulmonary artery pulsatility index; PASP: pulmonary artery systolic pressure; PVR: pulmonary vascular resistance; TPG: transpulmonary gradient.</p>
            </fn>
          </table-wrap-foot>
        </table-wrap>
      </sec>
      <sec>
        <title>Echocardiography</title>
        <p>Transthoracic echocardiography was performed by two experienced examiners (Berger SV e Menegazzo WR), blinded to the results of the RHC measurements. All examinations were performed using the Philips Epiq CVx system. To assess interobserver variability, a preliminary study was conducted in a subset of 10 patients, who were not included in the 34 patients of the study sample. The evaluation was performed by the two echocardiographers. Echocardiography was performed on the same day of the RHC, with the shortest possible interval between the two tests, and patients were required to rest for at least 10 minutes before the exam. Measurements obtained via echocardiography followed the guidelines established by the American Society of Echocardiography.<sup><xref ref-type="bibr" rid="B10">10</xref></sup></p>
        <p>CO was calculated using the formula: CO = LVOT-VTI &#215; LVOT area &#215; heart rate. CPO was derived using the formula: CPO = CO &#215; MAP / 451, and PAPI was calculated using the formula: PAPI = (PASP &#8722; PADP) / eRAP [estimated right atrial pressure], where eRAP indicates estimated right atrial pressure. CVP was estimated based on the maximum diameter of the inferior vena cava (greater or less than 2.1 cm) and its variability during inspiration (greater or less than 50%). Ejection fraction was assessed using Simpson's method. PASP, PADP, mean pulmonary artery pressure (MPAP), and other derived formulas are described in <xref ref-type="table" rid="t2">Table 2</xref>.</p>
        <table-wrap id="t2">
          <label>Table 2</label>
          <caption>
            <title>Echocardiographic parameters</title>
          </caption>
          <table frame="hsides" rules="groups">
            <colgroup width="50%">
              <col/>
              <col/>
            </colgroup>
            <thead style="border-top: thin solid; border-bottom: thin solid; border-color: #000000">
              <tr style="background-color:#C58874">
                <th align="left" valign="middle">Parameter</th>
                <th align="center" valign="middle">Formula</th>
              </tr>
            </thead>
            <tbody style="border-bottom: thin solid; border-color: #000000">
              <tr>
                <td align="left" valign="middle">CO</td>
                <td align="center" valign="middle">LVOT-VTI &#215; LVOT area &#215; heart rate</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">CPO</td>
                <td align="center" valign="middle">CO &#215; MAP / 451</td>
              </tr>
              <tr>
                <td align="left" valign="middle">PAPI</td>
                <td align="center" valign="middle">(PASP &#8722; PADP) / eRAP</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">PASP</td>
                <td align="center" valign="middle">TR peak gradient + CVP</td>
              </tr>
              <tr>
                <td align="left" valign="middle">PADP</td>
                <td align="center" valign="middle">4 &#215; (end-diastolic pulmonary regurgitation velocity)&#178; + CVP</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">MPAP</td>
                <td align="center" valign="middle">4 &#215; (protodiastolic pulmonary regurgitation velocity)&#178; + CVP</td>
              </tr>
            </tbody>
          </table>
          <table-wrap-foot>
            <fn id="TFN2">
              <p>CO: cardiac output; CPO: cardiac power output; CVP: central venous pressure; eRAP: estimated right atrial pressure; LVOT: left ventricular outflow tract; LVOT-VTI: left ventricular outflow tract velocity&#8211;time integral; MAP: mean arterial pressure; MPAP: mean pulmonary artery pressure; PADP: pulmonary artery diastolic pressure; PAPI: pulmonary artery pulsatility index; PASP: pulmonary artery systolic pressure; TR: tricuspid regurgitation.</p>
            </fn>
          </table-wrap-foot>
        </table-wrap>
      </sec>
      <sec>
        <title>Statistical analysis</title>
        <p>The normality of continuous variables was assessed using histograms and the Shapiro&#8211;Wilk test. All continuous variables showed a normal distribution and were therefore expressed as mean &#177; standard deviation. Categorical variables were expressed as absolute and relative frequencies (n, %). Comparisons between groups were performed using the unpaired Student's t-test. For correlation analysis between invasive hemodynamic and echocardiographic measures, Pearson's correlation coefficient was used, as all continuous variables were normally distributed. Interobserver agreement was evaluated using intraclass correlation coefficient analysis, based on a two-way random-effects model, assessing consistency and average measurements. A statistical significance level of 5% (p &lt; 0.05) was adopted. All statistical analyses were conducted using SPSS Statistics for Windows, Version 26.0 (IBM Corp., Armonk, NY, United States).</p>
        <p>A sample of 27 patients was required based on the correlation between LVOT-VTI and stroke volume measured by PAC of r = 0.52 (95%, p &lt; 0.01) in a prior study,<sup><xref ref-type="bibr" rid="B15">15</xref></sup> assuming an alpha value of 0.05 and a power of 80% to identify a similar correlation in our sample. The correlation between LVOT-VTI and CPO assessed via PAC was not utilized in the sample size calculation because such data were not available in the published literature at the time of the study design.</p>
      </sec>
    </sec>
    <sec sec-type="results">
      <title>Results</title>
      <p>Between May 2023 and June 2024, a total of 34 patients were included in the study. The mean age was 50.8 &#177; 6.2 years, 61.7% were male, and 82.4% of patients had nonischemic HF. The mean left ventricular ejection fraction was 21.1% &#177; 6.6%. The majority of the sample consisted of inpatients (67.4%), whereas 26.5% were receiving inotropic therapy at the time of the examinations. <xref ref-type="table" rid="t3">Table 3</xref> provides an overview of the patient baseline characteristics and ongoing therapies.</p>
      <table-wrap id="t3">
        <label>Table 3</label>
        <caption>
          <title>Baseline characteristics and ongoing therapies</title>
        </caption>
        <table frame="hsides" rules="groups">
          <colgroup width="33%">
            <col/>
            <col/>
            <col/>
          </colgroup>
          <thead style="border-top: thin solid; border-bottom: thin solid; border-color: #000000">
            <tr style="background-color:#C58874">
              <th align="left" valign="middle">Parameter</th>
              <th align="center" valign="middle">Mean (SD) or Median (IQR)</th>
              <th align="center" valign="middle">n (%)</th>
            </tr>
          </thead>
          <tbody style="border-bottom: thin solid; border-color: #000000">
            <tr>
              <td align="left" valign="middle">Age (years)</td>
              <td align="center" valign="middle">50.8 &#177; 6.2</td>
              <td align="center" valign="middle">34 (100)</td>
            </tr>
            <tr style="background-color:#E8CCBF">
              <td align="left" valign="middle">Male sex (%)</td>
              <td align="center" valign="middle">61.7</td>
              <td align="center" valign="middle">34 (100)</td>
            </tr>
            <tr>
              <td align="left" valign="middle">Nonischemic HF etiology (%)</td>
              <td align="left" valign="middle"/>
              <td align="center" valign="middle">28 (82.4)</td>
            </tr>
            <tr style="background-color:#E8CCBF">
              <td align="left" valign="middle">Heart rate (bpm)</td>
              <td align="center" valign="middle">78.2 &#177; 15.2</td>
              <td align="center" valign="middle">34 (100)</td>
            </tr>
            <tr>
              <td align="left" valign="middle">Systolic blood pressure (mmHg)</td>
              <td align="center" valign="middle">101.6 &#177; 17.9</td>
              <td align="center" valign="middle">34 (100)</td>
            </tr>
            <tr style="background-color:#E8CCBF">
              <td align="left" valign="middle">Diastolic blood pressure (mmHg)</td>
              <td align="center" valign="middle">66.2 &#177; 13.2</td>
              <td align="center" valign="middle">34 (100)</td>
            </tr>
            <tr>
              <td align="left" valign="middle">MAP (mmHg)</td>
              <td align="center" valign="middle">73.4 &#177; 11.0</td>
              <td align="center" valign="middle">34 (100)</td>
            </tr>
            <tr style="background-color:#E8CCBF">
              <td align="left" valign="middle">Weight (kg)</td>
              <td align="center" valign="middle">77.0 &#177; 18.9</td>
              <td align="center" valign="middle">34 (100)</td>
            </tr>
            <tr>
              <td align="left" valign="middle">Height (cm)</td>
              <td align="center" valign="middle">167.6 &#177; 10.6</td>
              <td align="center" valign="middle">34 (100)</td>
            </tr>
            <tr style="background-color:#E8CCBF">
              <td align="left" valign="middle">Use of CRT-D (%)</td>
              <td align="left" valign="middle"/>
              <td align="center" valign="middle">3 (8.8)</td>
            </tr>
            <tr>
              <td align="left" valign="middle">ARNI (%)</td>
              <td align="left" valign="middle"/>
              <td align="center" valign="middle">10 (41.2)</td>
            </tr>
            <tr style="background-color:#E8CCBF">
              <td align="left" valign="middle">ACE inhibitors/ARBs (%)</td>
              <td align="left" valign="middle"/>
              <td align="center" valign="middle">14 (38.2)</td>
            </tr>
            <tr>
              <td align="left" valign="middle">Mineralocorticoid receptor antagonists (%)</td>
              <td align="left" valign="middle"/>
              <td align="center" valign="middle">31 (91.2)</td>
            </tr>
            <tr style="background-color:#E8CCBF">
              <td align="left" valign="middle">Beta-blockers (%)</td>
              <td align="left" valign="middle"/>
              <td align="center" valign="middle">31 (91.2)</td>
            </tr>
            <tr>
              <td align="left" valign="middle">Sodium-glucose cotransporter-2 inhibitors (%)</td>
              <td align="left" valign="middle"/>
              <td align="center" valign="middle">22 (64.7)</td>
            </tr>
            <tr style="background-color:#E8CCBF">
              <td align="left" valign="middle">Digoxin (%)</td>
              <td align="left" valign="middle"/>
              <td align="center" valign="middle">17 (50.0)</td>
            </tr>
            <tr>
              <td align="left" valign="middle">Hydralazine plus nitrates (%)</td>
              <td align="left" valign="middle"/>
              <td align="center" valign="middle">6 (17.6)</td>
            </tr>
          </tbody>
        </table>
        <table-wrap-foot>
          <fn id="TFN3">
            <p>ACE: angiotensin-converting enzyme; ARB: angiotensin II receptor blocker; ARNI: angiotensin receptor&#8211;neprilysin inhibitor; CRT-D: cardiac resynchronization therapy with defibrillator; HF: heart failure; IQR: interquartile range; SD: standard deviation; MAP: mean arterial pressure.</p>
          </fn>
        </table-wrap-foot>
      </table-wrap>
      <p>All patients receiving inotropic support were classified as having INTERMACS III HF, as their mean serum lactate was 1.4 &#177; 0.2 mmol/L, and none of them were receiving vasopressor support (clinical characteristics in <xref ref-type="sec" rid="sec1">Supplementary Table S1</xref>).</p>
      <p>Regarding clinical characteristics reviewed retrospectively in medical records, 24 of 34 patients underwent cardiopulmonary exercise testing, and the mean peak oxygen consumption was 15.9 &#177; 5.3 mL/kg/min; 9 patients (26.4%) underwent orthotopic heart transplantation, and 5 (14%) died.</p>
      <sec>
        <title>PAC parameters</title>
        <p>PAC measurements demonstrated elevated pulmonary pressures and impaired left and right ventricular hemodynamic parameters. Detailed invasive hemodynamic measurements are presented in <xref ref-type="table" rid="t4">Table 4</xref>.</p>
        <table-wrap id="t4">
          <label>Table 4</label>
          <caption>
            <title>PAC parameters</title>
          </caption>
          <table frame="hsides" rules="groups">
            <colgroup width="33%">
              <col/>
              <col/>
              <col/>
            </colgroup>
            <thead style="border-top: thin solid; border-bottom: thin solid; border-color: #000000">
              <tr style="background-color:#C58874">
                <th align="left" valign="middle">Measure</th>
                <th align="center" valign="middle">Mean (&#177; SD)</th>
                <th align="center" valign="middle">n (%)</th>
              </tr>
            </thead>
            <tbody style="border-bottom: thin solid; border-color: #000000">
              <tr>
                <td align="left" valign="middle">CO (L/min)</td>
                <td align="center" valign="middle">4.2 &#177; 1.2</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">CI (L/min/m&#178;)</td>
                <td align="center" valign="middle">2.2 &#177; 0.5</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">PAOP (mmHg)</td>
                <td align="center" valign="middle">18.6 &#177; 6.2</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">CPO (W)</td>
                <td align="center" valign="middle">0.7 &#177; 0.2</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">PAPI</td>
                <td align="center" valign="middle">3.2 &#177; 1.5</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">RVSWI (mmHg&#183;mL/m&#178;)</td>
                <td align="center" valign="middle">7.7 &#177; 2.9</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">CVP (mmHg)</td>
                <td align="center" valign="middle">7.7 &#177; 4.1</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">PASP (mmHg)</td>
                <td align="center" valign="middle">41.2 &#177; 10.3</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">MPAP (mmHg)</td>
                <td align="center" valign="middle">27.8 &#177; 7.7</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">PADP (mmHg)</td>
                <td align="center" valign="middle">20.8 &#177; 6.2</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">PVR (Wood units)</td>
                <td align="center" valign="middle">2.3 &#177; 1.5</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">Transpulmonary gradient (mmHg)</td>
                <td align="center" valign="middle">9.3 &#177; 4.7</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">CVP over PAOP</td>
                <td align="center" valign="middle">0.42 &#177; 0.2</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
            </tbody>
          </table>
          <table-wrap-foot>
            <fn id="TFN4">
              <p>I: cardiac index; CO: cardiac output; CPO: cardiac power output; CVP: central venous pressure; MPAP: mean pulmonary artery pressure; PADP: pulmonary artery diastolic pressure; PAOP: pulmonary artery occlusion pressure; PAPI: pulmonary artery pulsatility index; PASP: pulmonary artery systolic pressure; PVR: pulmonary vascular resistance; RVSWI: right ventricular stroke work index; SD: standard deviation.</p>
            </fn>
          </table-wrap-foot>
        </table-wrap>
      </sec>
      <sec>
        <title>Echocardiographic parameters</title>
        <p>Echocardiography demonstrated marked left ventricular dilation and mild right ventricular enlargement, accompanied by severe biventricular systolic dysfunction. Pulmonary artery pressures were elevated, consistent with the advanced HF profile of the study population. Detailed echocardiographic structural, functional, and hemodynamic parameters are presented in <xref ref-type="table" rid="t5">Table 5</xref>.</p>
        <table-wrap id="t5">
          <label>Table 5</label>
          <caption>
            <title>Echocardiographic measurements</title>
          </caption>
          <table frame="hsides" rules="groups">
            <colgroup width="33%">
              <col/>
              <col/>
              <col/>
            </colgroup>
            <thead style="border-top: thin solid; border-bottom: thin solid; border-color: #000000">
              <tr style="background-color:#C58874">
                <th align="left" valign="middle">Parameter</th>
                <th align="center" valign="middle">Mean (SD)</th>
                <th align="center" valign="middle">n (%)</th>
              </tr>
            </thead>
            <tbody style="border-bottom: thin solid; border-color: #000000">
              <tr>
                <td align="left" valign="middle">LA diameter (mm)</td>
                <td align="center" valign="middle">48 (&#177; 10.7)</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">LA reservoir strain</td>
                <td align="center" valign="middle">9.9 (&#177; 7.2)</td>
                <td align="center" valign="middle">32 (94.1)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">LA conduit strain</td>
                <td align="center" valign="middle">&#8722;6.7 (&#177; 4.6)</td>
                <td align="center" valign="middle">32 (94.1)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">LA contractile strain</td>
                <td align="center" valign="middle">&#8722;3.3 (&#177; 4.8)</td>
                <td align="center" valign="middle">32 (94.1)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">LV strain (%)</td>
                <td align="center" valign="middle">&#8722;6.6 (&#177; 3.2)</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">LVDD (mm)</td>
                <td align="center" valign="middle">71.8 (&#177; 7.7)</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">LVSD (mm)</td>
                <td align="center" valign="middle">64.8 (&#177; 8.5)</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">LVDV (mL)</td>
                <td align="center" valign="middle">236.9 (&#177; 69.7)</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">LVSV (mL)</td>
                <td align="center" valign="middle">189.2 (&#177; 62.3)</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">LVEF (%)</td>
                <td align="center" valign="middle">21.1 (&#177; 6.6)</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">CO (L/min)</td>
                <td align="center" valign="middle">3.6 (&#177; 1.2)</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">CPO (W)</td>
                <td align="center" valign="middle">0.61 (&#177; 0.35)</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">LVOT-VTI (cm)</td>
                <td align="center" valign="middle">12.8 (&#177; 4.3)</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">E/e&#8242; ratio</td>
                <td align="center" valign="middle">18.0 (&#177; 7.8)</td>
                <td align="center" valign="middle">32 (94.1)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">PAPI</td>
                <td align="center" valign="middle">4.4 (&#177; 3.7)</td>
                <td align="center" valign="middle">16 (47)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">CVP (mmHg)</td>
                <td align="center" valign="middle">7.29 (&#177; 4.8)</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">PASP (mmHg)</td>
                <td align="center" valign="middle">44.1 (&#177; 14.8)</td>
                <td align="center" valign="middle">27 (79.4)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">MPAP (mmHg)</td>
                <td align="center" valign="middle">28.8 (&#177; 9.8)</td>
                <td align="center" valign="middle">18 (52.9)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">PADP (mmHg)</td>
                <td align="center" valign="middle">20.2 (&#177; 7.7)</td>
                <td align="center" valign="middle">16 (47)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">TAPSE (mm)</td>
                <td align="center" valign="middle">16.1 (&#177; 4.1)</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">S&#8242; wave velocity (cm/s)</td>
                <td align="center" valign="middle">8.8 (&#177; 2.1)</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">RV free wall strain (%)</td>
                <td align="center" valign="middle">&#8722;14.0 (&#177; 7.3)</td>
                <td align="center" valign="middle">33 (97)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">FAC (%)</td>
                <td align="center" valign="middle">27.8 (&#177; 9.3)</td>
                <td align="center" valign="middle">33 (97)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">RV basal diameter (mm)</td>
                <td align="center" valign="middle">43.8 (&#177; 8.4)</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
            </tbody>
          </table>
          <table-wrap-foot>
            <fn id="TFN5">
              <p>CO: cardiac output; CPO: cardiac power output; CVP: central venous pressure; E/e&#8242;: ratio of early mitral inflow velocity (E) to early diastolic mitral annular velocity (e&#8242;); FAC: fractional area change; LA: left atrium; LV: left ventricle; LVDD: left ventricular diastolic diameter; LVSD: left ventricular systolic diameter; LVDV: left ventricular diastolic volume; LVSV: left ventricular systolic volume; LVEF: left ventricular ejection fraction; LVOT-VTI: left ventricular outflow tract velocity&#8211;time integral; MPAP: mean pulmonary artery pressure; PADP: pulmonary artery diastolic pressure; PAPI: pulmonary artery pulsatility index; PASP: pulmonary artery systolic pressure; RV: right ventricle; S&#8242;: systolic velocity of the tricuspid annulus; SD: standard deviation; TAPSE: tricuspid annular plane systolic excursion.</p>
            </fn>
          </table-wrap-foot>
        </table-wrap>
        <p>Echocardiographic PAPI was successfully obtained in 16 of the 34 enrolled patients, whereas it was possible to estimate MPAP and PADP in 18 and 16 patients, respectively, owing to the absence of pulmonary regurgitation required for their calculation.</p>
        <p>Interobserver agreement was excellent for CPO, LVOT-VTI, left ventricular ejection fraction, and E/e' ratio, whereas PAPI and fractional area change showed poor agreement (<xref ref-type="sec" rid="sec1">Supplementary Table S2</xref>).</p>
      </sec>
      <sec>
        <title>Correlation between invasive and noninvasive hemodynamic measures</title>
        <p>This study demonstrated a correlation between the invasive and echocardiographic assessments of CPO (<xref ref-type="fig" rid="f1">Figure 1</xref>). The CPO measured via PAC showed a positive correlation with CO obtained by echocardiography (r = 0.616, p &lt; 0.001). Similarly, a positive correlation was observed between CPO measured via PAC and LVOT-VTI (<xref ref-type="fig" rid="f2">Figure 2</xref>). There was also a positive correlation between CPO assessed by PAC and left ventricular ejection fraction, with a correlation coefficient of 0.365 (p &lt; 0.05).</p>
        <fig id="f1">
          <label>Figure 1</label>
          <caption>
            <title>Correlation analysis for CPO assessed by PAC and echocardiography. r = 0.737 (p &lt; 0.001).</title>
          </caption>
          <graphic xlink:href="2675-312X-abcic-39-03-e20260059-0059i-gf02.tif"/></fig>
        <fig id="f2">
          <label>Figure 2</label>
          <caption>
            <title>Correlation analysis for CPO and LVOT-VTI. r = 0.469 (p &lt; 0.01)</title>
          </caption>
          <graphic xlink:href="2675-312X-abcic-39-03-e20260059-0059i-gf03.tif"/></fig>
        <p>Regarding the assessment of right ventricular function, correlations were detected between PAPI assessed by PAC and by echocardiography (<xref ref-type="fig" rid="f3">Figure 3</xref>). Furthermore, PAPI measured via PAC correlated with tricuspid annular plane systolic excursion (TAPSE), with r = 0.553 (p &lt; 0.01), and right ventricular free wall strain, with a negative correlation coefficient of r = &#8722;0.344 (p &lt; 0.05). Additionally, a positive correlation was observed between PAPI assessed by PAC and peak systolic velocity at the tricuspid annulus (S' wave), with a correlation coefficient of 0.356 (p &lt; 0.05).</p>
        <fig id="f3">
          <label>Figure 3</label>
          <caption>
            <title>Correlation analysis for PAPI assessed by PAC and echocardiography. r = 0.604 (p &lt; 0.05)</title>
          </caption>
          <graphic xlink:href="2675-312X-abcic-39-03-e20260059-0059i-gf04.tif"/></fig>
        <p>With respect to LVOT-VTI, in addition to the previously mentioned correlation with PAC-derived CPO, correlation was observed between LVOT-VTI and CO measured by PAC (r = 0.538, p &lt; 0.01), as well as cardiac index measured by PAC (r = 0.542, p &lt; 0.01).</p>
      </sec>
      <sec>
        <title>Sensitivity analysis</title>
        <p>A sensitivity analysis was conducted to evaluate the population receiving inotropic support. The correlation between invasive and echocardiographic CPO was higher in this subgroup compared to the overall population: r = 0.812 (p = 0.008). Additionally, a sensitivity analysis was also conducted in patients with CPO &lt; 0.6 W. In this subset, the correlation between invasive and echocardiographic CPO was r = 0.704 (p = 0.005). In both groups, it was not possible to assess the correlation between invasive and echocardiographic PAPI because noninvasive PAPI measurement was feasible in only 3 of the 9 patients included in this subgroup.</p>
      </sec>
    </sec>
    <sec sec-type="discussion">
      <title>Discussion</title>
      <p>The assessment of correlations between invasive and noninvasive hemodynamic measurements aims to identify echocardiographic parameters that reliably reflect prognostically significant hemodynamic variables, such as CPO and PAPI. This approach intends to provide a more practical and safer diagnostic strategy for patients with advanced HF by minimizing the evaluation time and risks associated with invasive procedures.</p>
      <p>As reported by Burstein et al., in a retrospective cohort study, noninvasive CPO demonstrated a prognostic role in patients admitted to cardiac intensive care units. The study analyzed nearly 5000 patients, with 50% presenting with decompensated HF. CPO below 0.89 &#177; 0.37 W was associated with greater hospital mortality.<sup><xref ref-type="bibr" rid="B16">16</xref></sup> Echocardiographic PAPI also demonstrated prognostic value, being associated with 60-day mortality in acute decompensated HF-related CS (hazard ratio 2.96, 95% confidence interval 1.23&#8211;7.17, p = 0.02).<sup><xref ref-type="bibr" rid="B12">12</xref></sup> LVOT-VTI, as demonstrated by Kentzer et al. and Machado et al., also demonstrated significant prognostic value among cardiology patients, including those with HF and acute myocardial infarction.<sup><xref ref-type="bibr" rid="B9">9</xref>,<xref ref-type="bibr" rid="B17">17</xref></sup></p>
      <p>In our study, regarding left ventricle function parameters, invasively measured CPO and CPO estimated by echocardiography showed the strongest correlation. This association was further enhanced in the subgroup of patients receiving inotropic support. Furthermore, CPO measured by PAC also demonstrated correlation with CO assessed through echocardiography and with the LVOT-VTI and left ventricular ejection fraction.</p>
      <p>Regarding PAPI, the results revealed correlation between its invasive measurement via PAC and its echocardiographic estimation, as well as with TAPSE. The correlations between PAPI and S' wave velocity and between PAPI and right ventricular free wall strain were weaker. Based on literature review, this appears to be the first study to evaluate the correlations between invasive CPO and PAPI with echocardiographic measurements in patients with HFrEF.</p>
      <p>Stein et al. and Temporelli et al. reported a strong correlation between invasive and echocardiographic hemodynamic measurements in patients with chronic HF; however, CPO, PAPI and LVOT-VTI were not included among the variables analyzed in these studies.<sup><xref ref-type="bibr" rid="B13">13</xref>,<xref ref-type="bibr" rid="B14">14</xref></sup> Frea et al. published the largest study to date investigating the correlation between invasive and echocardiographic hemodynamic parameters in CS.<sup><xref ref-type="bibr" rid="B9">9</xref></sup> Their population consisted of patients with CS secondary to decompensated HF. In our cohort, 26.5% of patients were receiving inotropic support and classified as having INTERMACS III HF. Although our population had normal lactate levels and were not on vasopressor therapy at the time of evaluation, these two populations may share similar pathophysiological conditions. In the study by Frea et al.,<sup><xref ref-type="bibr" rid="B12">12</xref></sup> correlation between the two methods showed a Pearson coefficient r = 0.82, p &lt; 0.001 for CPO. The results of our study were in line with these findings, especially among patient in INTERMACS III, given that CPO measured by PAC and echocardiography showed the strongest correlation between the two methods in our population (r = 0.73, p &lt; 0.001), which was even greater in patients receiving inotropic support (r = 0.81, p = 0.008). Our study reaffirms the strength of correlation between invasive and echocardiographic CPO and its reproducibility, extending the findings observed in CS to patients with chronic and acutely decompensated HFrEF.</p>
      <p>Frea et al.<sup><xref ref-type="bibr" rid="B12">12</xref></sup> also demonstrated a strong correlation between invasive and echocardiographic PAPI assessments. One notable difference between the two studies lies in the reproducibility of echocardiographic PAPI. In the cited study, PAPI estimation was feasible in 97 out of 101 patients, whereas in our study, it was achievable in only 16 of 34 patients. Pulmonary regurgitation is a rare finding on echocardiography in patients with pulmonary hypertension, consequently reducing the accuracy of methods that evaluate measures derived from it.<sup><xref ref-type="bibr" rid="B18">18</xref></sup> There is also significant variability in PAC-derived PAPI thresholds capable of predicting adverse outcomes across different studied populations. Consequently, the cutoff values for PAPI differ between CS and HF.<sup><xref ref-type="bibr" rid="B19">19</xref>,<xref ref-type="bibr" rid="B20">20</xref></sup> For this reason, low sensitivity of pulmonary regurgitation and the distinction in PAPI thresholds between different populations may have contributed to the differences in reproducibility observed between the two studies. Therefore, based on our findings, we conclude that echocardiographic PAPI may not be a reliable diagnostic parameter in patients with chronic and acutely decompensated HF due to its low reproducibility.</p>
      <p>This study presents some limitations. First, the size of the analyzed population is a significant aspect to emphasize, especially after the publication by Frea et al.,<sup><xref ref-type="bibr" rid="B12">12</xref></sup> which occurred during the final recruitment phase of our study. Furthermore, the heterogeneity of our cohort represents another limitation, as our study includes individuals with diverse hemodynamic conditions and varying requirements for therapeutic support. To reduce population heterogeneity, we performed a sensitivity analysis among patients receiving inotropic support, attempting to exclude patients with less severe disease. The inability to obtain echocardiographic PAPI in part of the sample represents another limitation. Lastly, the extended interval between the two assessment methods may also be regarded as a potential limitation.</p>
    </sec>
    <sec sec-type="conclusions">
      <title>Conclusion</title>
      <p>This study demonstrated significant correlations between invasive and noninvasive hemodynamic measures in patients with HFrEF, particularly for prognostic parameters such as CPO, PAPI, and LVOT-VTI. CPO showed the strongest agreement between methods, especially in patients receiving inotropic support. While PAPI correlated across techniques, its limited reproducibility by echocardiography reduces its clinical utility in this population.</p>
    </sec>
  </body>
  <back>
    <fn-group>
      <fn fn-type="supported-by" id="fn1">
        <label>Sources of Funding</label>
        <p>This study was funded by the Fundo de Incentivo &#224; Pesquisa (FIPE).</p>
      </fn>
      <fn fn-type="other" id="fn2">
        <label>Study Association</label>
        <p>This article is part of the master's thesis submitted by Jo&#227;o Pedro da Rosa Barbato, from the Federal University of Rio Grande do Sul.</p>
      </fn>
      <fn fn-type="other" id="fn3">
        <label>Ethics Approval and Consent to Participate</label>
        <p>This study was approved by the Ethics Committee of Hospital de Cl&#237;nicas de Porto Alegre under the protocol number 5920490. All the procedures in this study were in accordance with the 1975 Helsinki Declaration, updated in 2013. Informed consent was obtained from all participants included in the study.</p>
      </fn>
      <fn fn-type="other" id="fn4">
        <label>Use of Artificial Intelligence</label>
        <p>The authors did not use any artificial intelligence tools in the development of this work.</p>
      </fn>
    </fn-group>
    <sec sec-type="data-availability" specific-use="data-in-article">
      <title>Availability of Research Data</title>
      <p>The underlying content of the research text is contained within the manuscript.</p>
    </sec>
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    <sec id="sec1" sec-type="supplementary-material">
      <title>*Supplemental Materials</title>
      <supplementary-material id="suppl1">
        <label>Supplemental Materials</label>
        <media mime-subtype="pdf" mimetype="application" xlink:href="https://minio.scielo.br/documentstore/2675-312X/VMHGNLDwVpYDWXsCdrbwNWs/c93ba0144c44ab2f5ea246ad94eac35d7fac8ebf.pdf"/>
        <p>For additional information, please <ext-link ext-link-type="uri" xlink:href="http://abcimaging.org/supplementary-material/2026/3903/ABCImag-2026-0059_AO_Material-Suplementar.pdf">click here</ext-link>.</p>
      </supplementary-material>
    </sec>
  </back>
  <sub-article article-type="translation" id="S1" xml:lang="pt">
    <front-stub>
      <article-id pub-id-type="doi">10.36660/abcimg.20260059</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Artigo Original</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Correla&#231;&#227;o Entre Medidas Hemodin&#226;micas Invasivas e Ecocardiogr&#225;ficas em Pacientes com Insufici&#234;ncia Card&#237;aca com Fra&#231;&#227;o de Eje&#231;&#227;o Reduzida</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0002-1568-5124</contrib-id>
          <name>
            <surname>Barbato</surname>
            <given-names>Jo&#227;o Pedro da Rosa</given-names>
          </name>
          <role>Concep&#231;&#227;o e desenho da pesquisa</role>
          <role>obten&#231;&#227;o de dados</role>
          <role>an&#225;lise e interpreta&#231;&#227;o dos dados</role>
          <role>an&#225;lise estat&#237;stica</role>
          <role>obten&#231;&#227;o de financiamento</role>
          <role>reda&#231;&#227;o do manuscrito</role>
          <role>revis&#227;o cr&#237;tica do manuscrito quanto ao conte&#250;do intelectual importante</role>
          <xref ref-type="aff" rid="aff3">
            <sup>1</sup>
          </xref>
          <xref ref-type="corresp" rid="c2"/>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0003-2150-6337</contrib-id>
          <name>
            <surname>Scolari</surname>
            <given-names>Fernando Luis</given-names>
          </name>
          <role>Concep&#231;&#227;o e desenho da pesquisa</role>
          <role>an&#225;lise e interpreta&#231;&#227;o dos dados</role>
          <role>an&#225;lise estat&#237;stica</role>
          <role>reda&#231;&#227;o do manuscrito</role>
          <role>revis&#227;o cr&#237;tica do manuscrito quanto ao conte&#250;do intelectual importante</role>
          <xref ref-type="aff" rid="aff3">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0002-5514-2562</contrib-id>
          <name>
            <surname>Machado</surname>
            <given-names>Guilherme Pinheiro</given-names>
          </name>
          <role>an&#225;lise e interpreta&#231;&#227;o dos dados</role>
          <role>an&#225;lise estat&#237;stica</role>
          <role>revis&#227;o cr&#237;tica do manuscrito quanto ao conte&#250;do intelectual importante</role>
          <xref ref-type="aff" rid="aff3">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0009-0001-7116-6193</contrib-id>
          <name>
            <surname>Amon</surname>
            <given-names>Andr&#233; Barcellos</given-names>
          </name>
          <role>obten&#231;&#227;o de dados</role>
          <role>an&#225;lise e interpreta&#231;&#227;o dos dados</role>
          <role>revis&#227;o cr&#237;tica do manuscrito quanto ao conte&#250;do intelectual importante</role>
          <xref ref-type="aff" rid="aff3">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0003-2402-2565</contrib-id>
          <name>
            <surname>Crivelaro</surname>
            <given-names>Pedro Castilhos de Freitas</given-names>
          </name>
          <role>obten&#231;&#227;o de dados</role>
          <role>revis&#227;o cr&#237;tica do manuscrito quanto ao conte&#250;do intelectual importante</role>
          <xref ref-type="aff" rid="aff3">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0001-8289-7357</contrib-id>
          <name>
            <surname>Menegazzo</surname>
            <given-names>Willian R.</given-names>
          </name>
          <role>Concep&#231;&#227;o e desenho da pesquisa</role>
          <role>obten&#231;&#227;o de dados</role>
          <role>an&#225;lise e interpreta&#231;&#227;o dos dados</role>
          <role>revis&#227;o cr&#237;tica do manuscrito quanto ao conte&#250;do intelectual importante</role>
          <xref ref-type="aff" rid="aff3">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0009-0002-5671-1453</contrib-id>
          <name>
            <surname>Berger</surname>
            <given-names>Solano Vinicius</given-names>
          </name>
          <role>Concep&#231;&#227;o e desenho da pesquisa</role>
          <role>obten&#231;&#227;o de dados</role>
          <role>an&#225;lise e interpreta&#231;&#227;o dos dados</role>
          <role>revis&#227;o cr&#237;tica do manuscrito quanto ao conte&#250;do intelectual importante</role>
          <xref ref-type="aff" rid="aff3">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0002-1989-1670</contrib-id>
          <name>
            <surname>Araujo</surname>
            <given-names>Gustavo Neves de</given-names>
          </name>
          <role>Concep&#231;&#227;o e desenho da pesquisa</role>
          <role>an&#225;lise e interpreta&#231;&#227;o dos dados</role>
          <role>an&#225;lise estat&#237;stica</role>
          <role>reda&#231;&#227;o do manuscrito</role>
          <role>revis&#227;o cr&#237;tica do manuscrito quanto ao conte&#250;do intelectual importante</role>
          <xref ref-type="aff" rid="aff4">
            <sup>2</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0001-7102-6644</contrib-id>
          <name>
            <surname>Valle</surname>
            <given-names>Felipe Homem</given-names>
          </name>
          <role>Concep&#231;&#227;o e desenho da pesquisa</role>
          <role>an&#225;lise e interpreta&#231;&#227;o dos dados</role>
          <role>reda&#231;&#227;o do manuscrito</role>
          <role>revis&#227;o cr&#237;tica do manuscrito quanto ao conte&#250;do intelectual importante</role>
          <xref ref-type="aff" rid="aff3">
            <sup>1</sup>
          </xref>
        </contrib>
        <contrib contrib-type="author">
          <contrib-id contrib-id-type="orcid">0000-0001-7596-2827</contrib-id>
          <name>
            <surname>Wainstein</surname>
            <given-names>Rodrigo Vugman</given-names>
          </name>
          <role>Concep&#231;&#227;o e desenho da pesquisa</role>
          <role>an&#225;lise e interpreta&#231;&#227;o dos dados</role>
          <role>reda&#231;&#227;o do manuscrito</role>
          <role>revis&#227;o cr&#237;tica do manuscrito quanto ao conte&#250;do intelectual importante</role>
          <xref ref-type="aff" rid="aff3">
            <sup>1</sup>
          </xref>
        </contrib>
        <aff id="aff3">
          <label>1</label>
          <addr-line>
            <named-content content-type="city">Porto Alegre</named-content>
            <named-content content-type="state">RS</named-content>
          </addr-line>
          <country country="BR">Brasil</country>
          <institution content-type="original">Hospital de Cl&#237;nicas de Porto Alegre, Porto Alegre, RS &#8211; Brasil</institution>
        </aff>
        <aff id="aff4">
          <label>2</label>
          <addr-line>
            <named-content content-type="city">Florian&#243;polis</named-content>
            <named-content content-type="state">RS</named-content>
          </addr-line>
          <country country="BR">Brasil</country>
          <institution content-type="original">Hospital da Unimed Grande Florian&#243;polis, Florian&#243;polis, RS &#8211; Brasil</institution>
        </aff>
      </contrib-group>
      <author-notes>
        <corresp id="c2"><label>Correspond&#234;ncia:</label><bold>Jo&#227;o Pedro da Rosa da Rosa Barbato</bold> &#8226; Hospital de Cl&#237;nicas de Porto Alegre. Rua Ramiro Barcelos, 2350. CEP: <postal-code>90410-000</postal-code>. Porto Alegre, RS &#8211; Brasil E-mail: <email>jpdarosa94@gmail.com</email> </corresp>
        <fn fn-type="coi-statement">
          <label>Potencial Conflito de Interesse</label>
          <p>Declaro n&#227;o haver conflito de interesses pertinentes.</p>
        </fn>
        <fn fn-type="edited-by">
          <label>Editor respons&#225;vel pela revis&#227;o:</label>
          <p>Marcelo Tavares</p>
        </fn>
      </author-notes>
      <abstract>
        <title>Resumo</title>
        <sec>
          <title>Introdu&#231;&#227;o:</title>
          <p>O manejo da insufici&#234;ncia card&#237;aca (IC) com fra&#231;&#227;o de eje&#231;&#227;o reduzida (ICFER) avan&#231;ou com o uso de marcadores hemodin&#226;micos invasivos, como a pot&#234;ncia card&#237;aca (CPO) e o &#237;ndice de pulsatilidade da art&#233;ria pulmonar (PAPI). Simultaneamente, cresceu o interesse em indicadores progn&#243;sticos n&#227;o invasivos, especialmente a integral velocidade&#8211;tempo do trato de sa&#237;da do ventr&#237;culo esquerdo (LVOT-VTI).</p>
        </sec>
        <sec>
          <title>Objetivo:</title>
          <p>O presente estudo visou avaliar a correla&#231;&#227;o entre par&#226;metros invasivos e ecocardiogr&#225;ficos, particularmente CPO, PAPI e LVOT-VTI, em pacientes com ICFER.</p>
        </sec>
        <sec>
          <title>M&#233;todos:</title>
          <p>Trata-se de um estudo transversal e unic&#234;ntrico que incluiu pacientes internados e ambulatoriais com ICFER cr&#244;nica est&#225;vel ou agudamente descompensada. Foram exclu&#237;dos aqueles com choque cardiog&#234;nico (CC). O cateterismo card&#237;aco direito (CCD) e o ecocardiograma foram realizados no mesmo dia. A signific&#226;ncia estat&#237;stica foi definida como um valor de p bicaudal &lt; 0,05.</p>
        </sec>
        <sec>
          <title>Resultados:</title>
          <p>Foram observadas correla&#231;&#245;es significativas entre a CPO invasiva e a CPO ecocardiogr&#225;fica (r = 0,737, p &lt; 0,001) e entre o PAPI invasivo e o PAPI ecocardiogr&#225;fico (r = 0,604, p &lt; 0,05). A LVOT-VTI apresentou correla&#231;&#227;o significativa com a CPO medida por cateter de art&#233;ria pulmonar (CAP) (r = 0,469, p &lt; 0,01). A PAPI ecocardiogr&#225;fica foi mensur&#225;vel em apenas 16 pacientes. Uma an&#225;lise de sensibilidade dos pacientes que receberam inotr&#243;picos mostrou uma correla&#231;&#227;o ainda mais forte entre a CPO invasiva e a CPO ecocardiogr&#225;fica (r = 0,812, p = 0,005).</p>
        </sec>
        <sec>
          <title>Conclus&#227;o:</title>
          <p>Em pacientes com ICFER, os par&#226;metros ecocardiogr&#225;ficos e hemodin&#226;micos invasivos apresentaram correla&#231;&#245;es significativas, particularmente a CPO, refor&#231;ando o potencial da ecocardiografia como uma alternativa para a avalia&#231;&#227;o hemodin&#226;mica. No entanto, a baixa viabilidade da medi&#231;&#227;o n&#227;o invasiva da PAPI destaca limita&#231;&#245;es importantes nessa popula&#231;&#227;o.</p>
        </sec>
      </abstract>
      <kwd-group xml:lang="pt">
        <title>Palavras-chave:</title>
        <kwd>Insufici&#234;ncia Card&#237;aca Sist&#243;lica</kwd>
        <kwd>Monitoriza&#231;&#227;o Hemodin&#226;mica</kwd>
        <kwd>Frequ&#234;ncia Card&#237;aca</kwd>
        <kwd>Ecocardiografia</kwd>
      </kwd-group>
      <funding-group>
        <funding-statement><bold>Fontes de Financiamento</bold> O presente estudo foi financiado pelo Fundo de Incentivo &#224; Pesquisa (FIPE).</funding-statement>
      </funding-group>
    </front-stub>
    <body>
      <fig id="f8">
        <caption>
          <title>CCD: cateterismo card&#237;aco direito; CPO: pot&#234;ncia card&#237;aca; eCPO: pot&#234;ncia card&#237;aca derivada da ecocardiografia; ePAPI: &#237;ndice de pulsatilidade da art&#233;ria pulmonar derivado da ecocardiografia; LVOT-VTI: integral velocidade&#8211;tempo do trato de sa&#237;da do ventr&#237;culo esquerdo; PAPI: &#237;ndice de pulsatilidade da art&#233;ria pulmonar.</title>
        </caption>
        <graphic xlink:href="2675-312X-abcic-39-03-e20260059-0059i-gf01-pt.tif"/></fig>
      <sec sec-type="intro">
        <title>Introdu&#231;&#227;o</title>
        <p>A insufici&#234;ncia card&#237;aca (IC) &#233; um problema de sa&#250;de global crescente, afetando cerca de 60 milh&#245;es de pessoas em todo o mundo. Avan&#231;os no tratamento card&#237;aco e a maior sobrevida dos pacientes contribu&#237;ram para o aumento da preval&#234;ncia dessa s&#237;ndrome.<sup><xref ref-type="bibr" rid="B1">1</xref></sup> O uso de cateter de art&#233;ria pulmonar (CAP) para avalia&#231;&#227;o hemodin&#226;mica permanece um pilar no manejo da IC. Essas medidas invasivas s&#227;o essenciais para o diagn&#243;stico e a otimiza&#231;&#227;o de estrat&#233;gias terap&#234;uticas tanto na IC cr&#244;nica quanto na descompensada, fornecendo informa&#231;&#245;es sobre a progress&#227;o da doen&#231;a e a resposta ao tratamento.<sup><xref ref-type="bibr" rid="B2">2</xref>,<xref ref-type="bibr" rid="B3">3</xref></sup> O uso de CAP aumentou nos &#250;ltimos anos, orientado por uma abordagem sistem&#225;tica que prioriza par&#226;metros com maior impacto progn&#243;stico, como a pot&#234;ncia card&#237;aca (CPO, do ingl&#234;s <italic>cardiac power output</italic>) e o &#237;ndice de pulsatilidade da art&#233;ria pulmonar (PAPI). Esses par&#226;metros hemodin&#226;micos tornaram-se ferramentas essenciais para determinar a necessidade de suporte circulat&#243;rio mec&#226;nico em pacientes com choque cardiog&#234;nico (CC).<sup><xref ref-type="bibr" rid="B4">4</xref></sup> Embora inicialmente estudados em pacientes com CC, a CPO e o PAPI tamb&#233;m apresentam valor progn&#243;stico significativo na insufici&#234;ncia card&#237;aca com fra&#231;&#227;o de eje&#231;&#227;o reduzida (ICFER) cr&#244;nica e agudamente descompensada.<sup><xref ref-type="bibr" rid="B5">5</xref>&#8211;<xref ref-type="bibr" rid="B7">7</xref></sup></p>
        <p>Pesquisas sobre medidas n&#227;o invasivas com valor progn&#243;stico em pacientes com cardiopatia tamb&#233;m se expandiram, visando reduzir o tempo de avalia&#231;&#227;o e melhorar a seguran&#231;a. Entre os par&#226;metros ecocardiogr&#225;ficos, a integral velocidade&#8211;tempo do trato de sa&#237;da do ventr&#237;culo esquerdo (LVOT-VTI) demonstrou bom valor progn&#243;stico em estudos observacionais.<sup><xref ref-type="bibr" rid="B8">8</xref>,<xref ref-type="bibr" rid="B9">9</xref></sup> A LVOT-VTI &#233; uma medida ecocardiogr&#225;fica derivada do Doppler que quantifica a dist&#226;ncia percorrida pelo sangue pelo trato de sa&#237;da do ventr&#237;culo esquerdo durante a s&#237;stole, servindo como um par&#226;metro fundamental na avalia&#231;&#227;o do volume sist&#243;lico, do d&#233;bito card&#237;aco (DC) e do estado hemodin&#226;mico global.<sup><xref ref-type="bibr" rid="B10">10</xref>,<xref ref-type="bibr" rid="B11">11</xref></sup></p>
        <p>A correla&#231;&#227;o entre medidas invasivas e n&#227;o invasivas em pacientes com CC associado &#224; IC descompensada aguda tem sido investigada recentemente, revelando associa&#231;&#245;es entre CPO e PAPI medidos via CAP e ecocardiografia.<sup><xref ref-type="bibr" rid="B12">12</xref></sup> Da mesma forma, a rela&#231;&#227;o entre par&#226;metros derivados do CAP e ecocardiogr&#225;ficos foi explorada em pacientes com IC cr&#244;nica;<sup><xref ref-type="bibr" rid="B13">13</xref>,<xref ref-type="bibr" rid="B14">14</xref></sup> no entanto, esses estudos n&#227;o focaram em par&#226;metros como CPO, PAPI e LVOT-VTI.</p>
        <p>Portanto, o objetivo do presente estudo foi avaliar a correla&#231;&#227;o entre medidas invasivas e n&#227;o invasivas em pacientes internados e ambulatoriais com ICFER cr&#244;nica est&#225;vel ou descompensada, com &#234;nfase em CPO, PAPI e LVOT-VTI. Os principais achados est&#227;o resumidos na <xref ref-type="fig" rid="f8">Figura Central</xref>.</p>
      </sec>
      <sec sec-type="methods">
        <title>M&#233;todos</title>
        <p>Trata-se de um estudo transversal e unic&#234;ntrico realizado em um hospital universit&#225;rio na Regi&#227;o Sul do Brasil. Os participantes com indica&#231;&#227;o de avalia&#231;&#227;o de rotina pela equipe de IC foram recrutados mediante busca ativa em listas de pacientes ambulatoriais e internados. O recrutamento ocorreu entre maio de 2023 e junho de 2024, utilizando-se contatos telef&#244;nicos e abordagem direta a pacientes hospitalizados. Todos os pacientes foram convidados a realizar ecocardiografia antes ou depois do cateterismo card&#237;aco direito (CCD). O protocolo de pesquisa foi aprovado pelo comit&#234; de &#233;tica institucional, e foi obtido o consentimento livre e esclarecido por escrito de todos os participantes.</p>
        <p>O estudo incluiu pacientes com 18 anos ou mais e diagn&#243;stico de ICFER (fra&#231;&#227;o de eje&#231;&#227;o do ventr&#237;culo esquerdo &lt; 40%). Foram exclu&#237;dos pacientes que apresentaram dificuldades t&#233;cnicas na obten&#231;&#227;o de medidas ecocardiogr&#225;ficas ou nos quais n&#227;o foi poss&#237;vel realizar as medidas do CCD. Tamb&#233;m foram exclu&#237;dos pacientes com CC, infec&#231;&#227;o ativa, em ventila&#231;&#227;o mec&#226;nica ou em hemodi&#225;lise. Pacientes que receberam diur&#233;ticos ou vasodilatadores entre os dois m&#233;todos de avalia&#231;&#227;o tamb&#233;m foram exclu&#237;dos.</p>
        <p>O protocolo do estudo envolveu a realiza&#231;&#227;o de uma avalia&#231;&#227;o ecocardiogr&#225;fica abrangente por dois ecocardiografistas experientes (SVB e WRM) no menor intervalo de tempo poss&#237;vel antes ou depois da avalia&#231;&#227;o hemodin&#226;mica invasiva com CAP. Todas as avalia&#231;&#245;es ocorreram dentro de um intervalo de 6 horas entre os dois m&#233;todos de exame.</p>
        <sec>
          <title>CCD</title>
          <p>A avalia&#231;&#227;o hemodin&#226;mica invasiva foi realizada por meio de CCD com CAP inserido pela t&#233;cnica de micropun&#231;&#227;o da veia bas&#237;lica direita ou da veia jugular interna direita. O n&#237;vel de refer&#234;ncia zero foi estabelecido na linha axilar m&#233;dia, e as medidas foram registradas ao final da expira&#231;&#227;o. O operador respons&#225;vel pelo CCD n&#227;o tinha conhecimento das medidas ecocardiogr&#225;ficas.</p>
          <p>O DC foi avaliado pela t&#233;cnica de termodilui&#231;&#227;o. A press&#227;o venosa central (PVC), as press&#245;es pulmonares e a press&#227;o de oclus&#227;o da art&#233;ria pulmonar (POAP) foram determinadas como os valores m&#233;dios de 8 ciclos card&#237;acos. A CPO foi calculada utilizando a press&#227;o arterial m&#233;dia (PAM), conforme a f&#243;rmula: CPO = DC &#215; PAM / 451. O PAPI foi calculado como: PAPI = PSAP &#151; PDAP / PVC, em que PSAP e PDAP indicam a press&#227;o sist&#243;lica e a press&#227;o diast&#243;lica da art&#233;ria pulmonar, respectivamente. Os demais par&#226;metros hemodin&#226;micos derivados foram calculados por meio das f&#243;rmulas descritas na <xref ref-type="table" rid="t6">Tabela 1</xref>.</p>
          <table-wrap id="t6">
            <label>Tabela 1</label>
            <caption>
              <title>Par&#226;metros derivados do CAP</title>
            </caption>
            <table frame="hsides" rules="groups">
              <colgroup width="50%">
                <col/>
                <col/>
              </colgroup>
              <thead style="border-top: thin solid; border-bottom: thin solid; border-color: #000000">
                <tr style="background-color:#C58874">
                  <th align="left" valign="middle">Par&#226;metro</th>
                  <th align="center" valign="middle">F&#243;rmula</th>
                </tr>
              </thead>
              <tbody style="border-bottom: thin solid; border-color: #000000">
                <tr>
                  <td align="left" valign="middle">CPO</td>
                  <td align="center" valign="middle">DC &#215; PAM / 451</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">PAPI</td>
                  <td align="center" valign="middle">(PSAP &#8722; PDAP) / PVC</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">GTP</td>
                  <td align="center" valign="middle">PMAP &#8722; POAP</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">RVP</td>
                  <td align="center" valign="middle">GTP / DC</td>
                </tr>
              </tbody>
            </table>
            <table-wrap-foot>
              <fn id="TFN6">
                <p>CPO: pot&#234;ncia card&#237;aca; DC: d&#233;bito card&#237;aco; GTP: gradiente transpulmonar; PAM: press&#227;o arterial m&#233;dia; PAPI: &#237;ndice de pulsatilidade da art&#233;ria pulmonar; PDAP: press&#227;o diast&#243;lica da art&#233;ria pulmonar; PMAP: press&#227;o m&#233;dia da art&#233;ria pulmonar; POAP: press&#227;o de oclus&#227;o da art&#233;ria pulmonar; PVC: press&#227;o venosa central; RVP: resist&#234;ncia vascular pulmonar.</p>
              </fn>
            </table-wrap-foot>
          </table-wrap>
        </sec>
        <sec>
          <title>Ecocardiografia</title>
          <p>A ecocardiografia transtor&#225;cica foi realizada por dois examinadores experientes (Berger SV e Menegazzo WR), que desconheciam os resultados das medi&#231;&#245;es do CCD. Todos os exames foram realizados em um sistema Philips Epiq CVx. Para avaliar a variabilidade interobservador, foi realizado um estudo preliminar com um subgrupo de 10 pacientes, os quais n&#227;o foram inclu&#237;dos na amostra de 34 pacientes do estudo. A avalia&#231;&#227;o foi realizada pelos dois ecocardiografistas. A ecocardiografia foi realizada no mesmo dia do CCD, com o menor intervalo poss&#237;vel entre os dois exames, e os pacientes permaneceram em repouso durante pelo menos 10 minutos antes do procedimento. As medi&#231;&#245;es obtidas por ecocardiografia seguiram as diretrizes estabelecidas pela American Society of Echocardiography.<sup><xref ref-type="bibr" rid="B10">10</xref></sup></p>
          <p>O DC foi calculado usando a f&#243;rmula: DC = LVOT-VTI &#215; &#225;rea do trato de sa&#237;da do ventr&#237;culo esquerdo &#215; frequ&#234;ncia card&#237;aca. A CPO foi derivada utilizando a f&#243;rmula: CPO = DC &#215; PAM / 451, e o PAPI foi calculado utilizando a f&#243;rmula: PAPI = (PSAP &#8722; PDAP) / eRAP [press&#227;o atrial direita estimada], em que eRAP indica a press&#227;o atrial direita estimada. A PVC foi estimada com base no di&#226;metro m&#225;ximo da veia cava inferior (maior ou menor que 2,1 cm) e em sua variabilidade durante a inspira&#231;&#227;o (maior ou menor que 50%). A fra&#231;&#227;o de eje&#231;&#227;o foi avaliada pelo m&#233;todo de Simpson. A PSAP, a PDAP, a press&#227;o m&#233;dia da art&#233;ria pulmonar (PMAP) e outras f&#243;rmulas derivadas est&#227;o descritas na <xref ref-type="table" rid="t7">Tabela 2</xref>.</p>
          <table-wrap id="t7">
            <label>Tabela 2</label>
            <caption>
              <title>Par&#226;metros ecocardiogr&#225;ficos</title>
            </caption>
            <table frame="hsides" rules="groups">
              <colgroup width="50%">
                <col/>
                <col/>
              </colgroup>
              <thead style="border-top: thin solid; border-bottom: thin solid; border-color: #000000">
                <tr style="background-color:#C58874">
                  <th align="left" valign="middle">Par&#226;metro</th>
                  <th align="center" valign="middle">F&#243;rmula</th>
                </tr>
              </thead>
              <tbody style="border-bottom: thin solid; border-color: #000000">
                <tr>
                  <td align="left" valign="middle">DC</td>
                  <td align="center" valign="middle">LVOT-VTI &#215; &#225;rea do LVOT &#215; frequ&#234;ncia card&#237;aca</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">CPO</td>
                  <td align="center" valign="middle">DC &#215; PAM / 451</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">PAPI</td>
                  <td align="center" valign="middle">(PSAP &#8722; PDAP) / eRAP</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">PSAP</td>
                  <td align="center" valign="middle">Gradiente de pico da RT + PVC</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">PDAP</td>
                  <td align="center" valign="middle">4 &#215; (velocidade de regurgita&#231;&#227;o pulmonar no final da di&#225;stole)&#178; + PVC</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">PMAP</td>
                  <td align="center" valign="middle">4 &#215; (velocidade de regurgita&#231;&#227;o pulmonar protodiast&#243;lica)&#178; + PVC</td>
                </tr>
              </tbody>
            </table>
            <table-wrap-foot>
              <fn id="TFN7">
                <p>CPO: pot&#234;ncia card&#237;aca; DC: d&#233;bito card&#237;aco; eRAP: press&#227;o atrial direita estimada; LVOT: trato de sa&#237;da do ventr&#237;culo esquerdo; LVOT-VTI: integral velocidade&#8211;tempo do trato de sa&#237;da do ventr&#237;culo esquerdo; PAM: press&#227;o arterial m&#233;dia; PAPI: &#237;ndice de pulsatilidade da art&#233;ria pulmonar; PDAP: press&#227;o diast&#243;lica da art&#233;ria pulmonar; PMAP: press&#227;o m&#233;dia da art&#233;ria pulmonar; PSAP: press&#227;o sist&#243;lica da art&#233;ria pulmonar; PVC: press&#227;o venosa central; RT: regurgita&#231;&#227;o tric&#250;spide.</p>
              </fn>
            </table-wrap-foot>
          </table-wrap>
        </sec>
        <sec>
          <title>An&#225;lise estat&#237;stica</title>
          <p>A normalidade das vari&#225;veis cont&#237;nuas foi avaliada por meio de histogramas e do teste de Shapiro-Wilk. Todas as vari&#225;veis cont&#237;nuas apresentaram distribui&#231;&#227;o normal e, portanto, foram expressas como m&#233;dia &#177; desvio-padr&#227;o. As vari&#225;veis categ&#243;ricas foram expressas em frequ&#234;ncias absolutas e relativas (n, %). As compara&#231;&#245;es entre os grupos foram realizadas utilizando o teste t de Student para amostras independentes. Para a an&#225;lise de correla&#231;&#227;o entre as medidas hemodin&#226;micas invasivas e ecocardiogr&#225;ficas, utilizou-se o coeficiente de correla&#231;&#227;o de Pearson, visto que todas as vari&#225;veis cont&#237;nuas apresentavam distribui&#231;&#227;o normal. A concord&#226;ncia interobservador foi avaliada por meio da an&#225;lise do coeficiente de correla&#231;&#227;o intraclasse, com base em um modelo de efeitos aleat&#243;rios de dois fatores, avaliando a consist&#234;ncia e as medidas m&#233;dias. Adotou-se um n&#237;vel de signific&#226;ncia estat&#237;stica de 5% (p &lt; 0,05). Todas as an&#225;lises estat&#237;sticas foram realizadas utilizando o software SPSS Statistics for Windows, vers&#227;o 26.0 (IBM Corp., Armonk, New York, Estados Unidos).</p>
          <p>Calculou-se a necessidade de uma amostra de 27 pacientes com base na correla&#231;&#227;o entre o LVOT-VTI e o volume sist&#243;lico medido por PAC de r = 0,52 (95%, p &lt; 0,01) observada em um estudo anterior,<sup><xref ref-type="bibr" rid="B15">15</xref></sup> assumindo um valor alfa de 0,05 e um poder estat&#237;stico de 80% para identificar uma correla&#231;&#227;o semelhante em nossa amostra. A correla&#231;&#227;o entre o LVOT-VTI e a CPO avaliada via PAC n&#227;o foi utilizada no c&#225;lculo do tamanho amostral, pois tais dados n&#227;o estavam dispon&#237;veis na literatura publicada &#224; &#233;poca do delineamento do estudo.</p>
        </sec>
      </sec>
      <sec sec-type="results">
        <title>Resultados</title>
        <p>Entre maio de 2023 e junho de 2024, foram inclu&#237;dos 34 pacientes no estudo. A idade m&#233;dia foi de 50,8 &#177; 6,2 anos, 61,7% eram do sexo masculino e 82,4% dos pacientes apresentavam IC n&#227;o isqu&#234;mica. A fra&#231;&#227;o de eje&#231;&#227;o do ventr&#237;culo esquerdo m&#233;dia foi de 21,1% &#177; 6,6%. A maior parte da amostra consistia em pacientes internados (67,4%), enquanto 26,5% recebiam suporte inotr&#243;pica no momento dos exames. A <xref ref-type="table" rid="t8">Tabela 3</xref> apresenta um panorama das caracter&#237;sticas basais dos pacientes e das terapias em curso.</p>
        <table-wrap id="t8">
          <label>Tabela 3</label>
          <caption>
            <title>Caracter&#237;sticas basais e terapias em curso</title>
          </caption>
          <table frame="hsides" rules="groups">
            <colgroup width="33%">
              <col/>
              <col/>
              <col/>
            </colgroup>
            <thead style="border-top: thin solid; border-bottom: thin solid; border-color: #000000">
              <tr style="background-color:#C58874">
                <th align="left" valign="middle">Par&#226;metro</th>
                <th align="center" valign="middle">M&#233;dia (DP) ou mediana (IIQ)</th>
                <th align="center" valign="middle">n (%)</th>
              </tr>
            </thead>
            <tbody style="border-bottom: thin solid; border-color: #000000">
              <tr>
                <td align="left" valign="middle">Idade (anos)</td>
                <td align="center" valign="middle">50,8 &#177; 6,2</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">Sexo masculino (%)</td>
                <td align="center" valign="middle">61,7</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">Etiologia n&#227;o isqu&#234;mica da IC (%)</td>
                <td align="left" valign="middle"/>
                <td align="center" valign="middle">28 (82,4)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">Frequ&#234;ncia card&#237;aca (bpm)</td>
                <td align="center" valign="middle">78,2 &#177; 15,2</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">Press&#227;o arterial sist&#243;lica (mmHg)</td>
                <td align="center" valign="middle">101,6 &#177; 17,9</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">Press&#227;o arterial diast&#243;lica (mmHg)</td>
                <td align="center" valign="middle">66,2 &#177; 13,2</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">PAM (mmHg)</td>
                <td align="center" valign="middle">73,4 &#177; 11,0</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">Peso (kg)</td>
                <td align="center" valign="middle">77,0 &#177; 18,9</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">Altura (cm)</td>
                <td align="center" valign="middle">167,6 &#177; 10,6</td>
                <td align="center" valign="middle">34 (100)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">Uso de TRC-D (%)</td>
                <td align="left" valign="middle"/>
                <td align="center" valign="middle">3 (8,8)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">ARNI (%)</td>
                <td align="left" valign="middle"/>
                <td align="center" valign="middle">10 (41,2)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">IECA/BRA (%)</td>
                <td align="left" valign="middle"/>
                <td align="center" valign="middle">14 (38,2)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">ARM (%)</td>
                <td align="left" valign="middle"/>
                <td align="center" valign="middle">31 (91,2)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">Betabloqueadores (%)</td>
                <td align="left" valign="middle"/>
                <td align="center" valign="middle">31 (91,2)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">Inibidores do cotransportador de s&#243;dio-glicose 2 (%)</td>
                <td align="left" valign="middle"/>
                <td align="center" valign="middle">22 (64,7)</td>
              </tr>
              <tr style="background-color:#E8CCBF">
                <td align="left" valign="middle">Digoxina (%)</td>
                <td align="left" valign="middle"/>
                <td align="center" valign="middle">17 (50,0)</td>
              </tr>
              <tr>
                <td align="left" valign="middle">Hidralazina e nitratos (%)</td>
                <td align="left" valign="middle"/>
                <td align="center" valign="middle">6 (17,6)</td>
              </tr>
            </tbody>
          </table>
          <table-wrap-foot>
            <fn id="TFN8">
              <p>ARM: antagonista do receptor mineralocorticoide; ARNI: inibidor do receptor de angiotensina-neprilisina; BRA: bloqueadores dos receptores de angiotensina II; DP: desvio-padr&#227;o; IC: insufici&#234;ncia card&#237;aca; IECA: inibidores da enzima conversora de angiotensina; IIQ: intervalo interquartil; TRC-D: terapia de ressincroniza&#231;&#227;o card&#237;aca com desfibrilador; PAM: press&#227;o arterial m&#233;dia.</p>
            </fn>
          </table-wrap-foot>
        </table-wrap>
        <p>Todos os pacientes que recebiam suporte inotr&#243;pico foram classificados como portadores de IC com perfil INTERMACS III, uma vez que o lactato s&#233;rico m&#233;dio era de 1,4 &#177; 0,2 mmol/L e nenhum deles recebia suporte vasopressor (caracter&#237;sticas cl&#237;nicas na <xref ref-type="sec" rid="sec2">Tabela Suplementar S1</xref>).</p>
        <p>Quanto &#224;s caracter&#237;sticas cl&#237;nicas revisadas retrospectivamente nos prontu&#225;rios, 24 dos 34 pacientes foram submetidos a teste cardiopulmonar de exerc&#237;cio, e o consumo de oxig&#234;nio de pico m&#233;dio foi de 15,9 &#177; 5,3 mL/kg/min; 9 pacientes (26,4%) foram submetidos a transplante card&#237;aco ortot&#243;pico e 5 (14%) faleceram.</p>
        <sec>
          <title>Par&#226;metros derivados do CAP</title>
          <p>As medidas obtidas pelo CAP demonstraram press&#245;es pulmonares elevadas e comprometimento dos par&#226;metros hemodin&#226;micos dos ventr&#237;culos esquerdo e direito. As medidas hemodin&#226;micas invasivas detalhadas est&#227;o apresentadas na <xref ref-type="table" rid="t9">Tabela 4</xref>.</p>
          <table-wrap id="t9">
            <label>Tabela 4</label>
            <caption>
              <title>Par&#226;metros derivados do CAP</title>
            </caption>
            <table frame="hsides" rules="groups">
              <colgroup width="33%">
                <col/>
                <col/>
                <col/>
              </colgroup>
              <thead style="border-top: thin solid; border-bottom: thin solid; border-color: #000000">
                <tr style="background-color:#C58874">
                  <th align="left" valign="middle">Medida</th>
                  <th align="center" valign="middle">M&#233;dia (&#177; DP)</th>
                  <th align="center" valign="middle">n (%)</th>
                </tr>
              </thead>
              <tbody style="border-bottom: thin solid; border-color: #000000">
                <tr>
                  <td align="left" valign="middle">DC (L/min)</td>
                  <td align="center" valign="middle">4,2 &#177; 1,2</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">&#205;ndice card&#237;aco (L/min/m&#178;)</td>
                  <td align="center" valign="middle">2,2 &#177; 0,5</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">POAP (mmHg)</td>
                  <td align="center" valign="middle">18,6 &#177; 6,2</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">CPO (W)</td>
                  <td align="center" valign="middle">0,7 &#177; 0,2</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">PAPI</td>
                  <td align="center" valign="middle">3,2 &#177; 1,5</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">ITSVD (mmHg&#183;mL/m&#178;)</td>
                  <td align="center" valign="middle">7,7 &#177; 2,9</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">PVC (mmHg)</td>
                  <td align="center" valign="middle">7,7 &#177; 4,1</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">PSAP (mmHg)</td>
                  <td align="center" valign="middle">41,2 &#177; 10,3</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">PMAP (mmHg)</td>
                  <td align="center" valign="middle">27,8 &#177; 7,7</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">PDAP (mmHg)</td>
                  <td align="center" valign="middle">20,8 &#177; 6,2</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">RVP (unidades Wood)</td>
                  <td align="center" valign="middle">2,3 &#177; 1,5</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">Gradiente transpulmonar (mmHg)</td>
                  <td align="center" valign="middle">9,3 &#177; 4,7</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">PVC / POAP</td>
                  <td align="center" valign="middle">0,42 &#177; 0,2</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
              </tbody>
            </table>
            <table-wrap-foot>
              <fn id="TFN9">
                <p>CPO: pot&#234;ncia card&#237;aca; DC: d&#233;bito card&#237;aco; DP: desvio-padr&#227;o; ITSVD: &#237;ndice de trabalho sist&#243;lico do ventr&#237;culo direito; PAPI: &#237;ndice de pulsatilidade da art&#233;ria pulmonar; PDAP: press&#227;o diast&#243;lica da art&#233;ria pulmonar; PMAP: press&#227;o m&#233;dia da art&#233;ria pulmonar; POAP: press&#227;o de oclus&#227;o da art&#233;ria pulmonar; PSAP: press&#227;o sist&#243;lica da art&#233;ria pulmonar; PVC: press&#227;o venosa central; RVP: resist&#234;ncia vascular pulmonar.</p>
              </fn>
            </table-wrap-foot>
          </table-wrap>
        </sec>
        <sec>
          <title>Par&#226;metros ecocardiogr&#225;ficos</title>
          <p>A ecocardiografia demonstrou dilata&#231;&#227;o acentuada do ventr&#237;culo esquerdo e discreto aumento do ventr&#237;culo direito, acompanhados de disfun&#231;&#227;o sist&#243;lica biventricular grave. A eleva&#231;&#227;o das press&#245;es da art&#233;ria pulmonar foi consistente com o perfil de IC avan&#231;ada da popula&#231;&#227;o do estudo. Os par&#226;metros ecocardiogr&#225;ficos estruturais, funcionais e hemodin&#226;micos detalhados est&#227;o apresentados na <xref ref-type="table" rid="t10">Tabela 5</xref>.</p>
          <table-wrap id="t10">
            <label>Tabela 5</label>
            <caption>
              <title>Medidas ecocardiogr&#225;ficas</title>
            </caption>
            <table frame="hsides" rules="groups">
              <colgroup width="33%">
                <col/>
                <col/>
                <col/>
              </colgroup>
              <thead style="border-top: thin solid; border-bottom: thin solid; border-color: #000000">
                <tr style="background-color:#C58874">
                  <th align="left" valign="middle">Par&#226;metro</th>
                  <th align="center" valign="middle">M&#233;dia (DP)</th>
                  <th align="center" valign="middle">n (%)</th>
                </tr>
              </thead>
              <tbody style="border-bottom: thin solid; border-color: #000000">
                <tr>
                  <td align="left" valign="middle">Di&#226;metro do AE (mm)</td>
                  <td align="center" valign="middle">48 (&#177; 10,7)</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">Strain de reservat&#243;rio do AE</td>
                  <td align="center" valign="middle">9,9 (&#177; 7,2)</td>
                  <td align="center" valign="middle">32 (94,1)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">Strain de conduto do AE</td>
                  <td align="center" valign="middle">&#8722;6,7 (&#177; 4,6)</td>
                  <td align="center" valign="middle">32 (94,1)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">Strain contr&#225;til do AE</td>
                  <td align="center" valign="middle">&#8722;3,3 (&#177; 4,8)</td>
                  <td align="center" valign="middle">32 (94,1)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">Strain do VE (%)</td>
                  <td align="center" valign="middle">&#8722;6,6 (&#177; 3,2)</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">DDVE (mm)</td>
                  <td align="center" valign="middle">71,8 (&#177; 7,7)</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">DSVE (mm)</td>
                  <td align="center" valign="middle">64,8 (&#177; 8,5)</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">VDVE (mL)</td>
                  <td align="center" valign="middle">236,9 (&#177; 69,7)</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">VSVE (mL)</td>
                  <td align="center" valign="middle">189,2 (&#177; 62,3)</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">FEVE (%)</td>
                  <td align="center" valign="middle">21,1 (&#177; 6,6)</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">DC (L/min)</td>
                  <td align="center" valign="middle">3,6 (&#177; 1,2)</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">CPO (W)</td>
                  <td align="center" valign="middle">0,61 (&#177; 0,35)</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">LVOT-VTI (cm)</td>
                  <td align="center" valign="middle">12,8 (&#177; 4,3)</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">E/e&#8242;</td>
                  <td align="center" valign="middle">18,0 (&#177; 7,8)</td>
                  <td align="center" valign="middle">32 (94,1)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">PAPI</td>
                  <td align="center" valign="middle">4,4 (&#177; 3,7)</td>
                  <td align="center" valign="middle">16 (47)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">PVC (mmHg)</td>
                  <td align="center" valign="middle">7,29 (&#177; 4,8)</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">PSAP (mmHg)</td>
                  <td align="center" valign="middle">44,1 (&#177; 14,8)</td>
                  <td align="center" valign="middle">27 (79,4)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">PMAP (mmHg)</td>
                  <td align="center" valign="middle">28,8 (&#177; 9,8)</td>
                  <td align="center" valign="middle">18 (52,9)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">PDAP (mmHg)</td>
                  <td align="center" valign="middle">20,2 (&#177; 7,7)</td>
                  <td align="center" valign="middle">16 (47)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">TAPSE (mm)</td>
                  <td align="center" valign="middle">16,1 (&#177; 4,1)</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">Velocidade da onda S&#8242; (cm/s)</td>
                  <td align="center" valign="middle">8,8 (&#177; 2,1)</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">Strain da parede livre do VD (%)</td>
                  <td align="center" valign="middle">&#8722;14,0 (&#177; 7,3)</td>
                  <td align="center" valign="middle">33 (97)</td>
                </tr>
                <tr>
                  <td align="left" valign="middle">FAC (%)</td>
                  <td align="center" valign="middle">27,8 (&#177; 9,3)</td>
                  <td align="center" valign="middle">33 (97)</td>
                </tr>
                <tr style="background-color:#E8CCBF">
                  <td align="left" valign="middle">Di&#226;metro basal do VD (mm)</td>
                  <td align="center" valign="middle">43,8 (&#177; 8,4)</td>
                  <td align="center" valign="middle">34 (100)</td>
                </tr>
              </tbody>
            </table>
            <table-wrap-foot>
              <fn id="TFN10">
                <p>AE: &#225;trio esquerdo; CPO: pot&#234;ncia card&#237;aca; DC: d&#233;bito card&#237;aco; DDVE: di&#226;metro diast&#243;lico do ventr&#237;culo esquerdo; DP: desvio-padr&#227;o; DSVE: di&#226;metro sist&#243;lico do ventr&#237;culo esquerdo; E/e&#8242;: rela&#231;&#227;o entre a velocidade de enchimento mitral precoce (E) e a velocidade diast&#243;lica precoce do anel mitral (e&#8242;); FAC: varia&#231;&#227;o da &#225;rea fracionada; FEVE: fra&#231;&#227;o de eje&#231;&#227;o do ventr&#237;culo esquerdo; LVOT-VTI: integral velocidade&#8211;tempo do trato de sa&#237;da do ventr&#237;culo esquerdo; PAPI: &#237;ndice de pulsatilidade da art&#233;ria pulmonar; PDAP: press&#227;o diast&#243;lica da art&#233;ria pulmonar; PMAP: press&#227;o m&#233;dia da art&#233;ria pulmonar; PSAP: press&#227;o sist&#243;lica da art&#233;ria pulmonar; PVC: press&#227;o venosa central; S&#8242;: velocidade sist&#243;lica do anel tric&#250;spide; TAPSE: excurs&#227;o sist&#243;lica do plano do anel tric&#250;spide; VD: ventr&#237;culo direito; VDVE: volume diast&#243;lico do ventr&#237;culo esquerdo; VE: ventr&#237;culo esquerdo; VSVE: volume sist&#243;lico do ventr&#237;culo esquerdo.</p>
              </fn>
            </table-wrap-foot>
          </table-wrap>
          <p>O PAPI ecocardiogr&#225;fico foi obtido com sucesso em 16 dos 34 pacientes inclu&#237;dos, enquanto foi poss&#237;vel estimar a PMAP e a PDAP em 18 e 16 pacientes, respectivamente, devido &#224; aus&#234;ncia de regurgita&#231;&#227;o pulmonar necess&#225;ria para o c&#225;lculo.</p>
          <p>A concord&#226;ncia interobservador foi excelente para CPO, LVOT-VTI, fra&#231;&#227;o de eje&#231;&#227;o do ventr&#237;culo esquerdo e rela&#231;&#227;o E/e', enquanto o PAPI e a varia&#231;&#227;o da &#225;rea fracionada apresentaram concord&#226;ncia insatisfat&#243;ria (<xref ref-type="sec" rid="sec2">Tabela Suplementar S2</xref>).</p>
        </sec>
        <sec>
          <title>Correla&#231;&#227;o entre medidas hemodin&#226;micas invasivas e n&#227;o invasivas</title>
          <p>O presente estudo demonstrou uma correla&#231;&#227;o entre a CPO invasiva e a CPO ecocardiogr&#225;fica (<xref ref-type="fig" rid="f5">Figura 1</xref>). A CPO medida via PAC apresentou correla&#231;&#227;o positiva com o DC obtido por ecocardiografia (r = 0,616; p &lt; 0,001). De modo semelhante, observou-se correla&#231;&#227;o positiva entre a CPO medida via PAC e o LVOT-VTI (<xref ref-type="fig" rid="f6">Figura 2</xref>). Houve tamb&#233;m correla&#231;&#227;o positiva entre a CPO avaliada por PAC e a fra&#231;&#227;o de eje&#231;&#227;o do ventr&#237;culo esquerdo, com coeficiente de correla&#231;&#227;o de 0,365 (p &lt; 0,05).</p>
          <fig id="f5">
            <label>Figura 1</label>
            <caption>
              <title>An&#225;lise de correla&#231;&#227;o entre a CPO avaliada por CAP e por ecocardiografia. r = 0,737 (p &lt; 0,001)</title>
            </caption>
            <graphic xlink:href="2675-312X-abcic-39-03-e20260059-0059i-gf02-pt.tif"/></fig>
          <fig id="f6">
            <label>Figura 2</label>
            <caption>
              <title>An&#225;lise de correla&#231;&#227;o entre a CPO e a LVOT-VTI. r = 0,469 (p &lt; 0,01).</title>
            </caption>
            <graphic xlink:href="2675-312X-abcic-39-03-e20260059-0059i-gf03-pt.tif"/></fig>
          <p>Quanto &#224; avalia&#231;&#227;o da fun&#231;&#227;o do ventr&#237;culo direito, foram observadas correla&#231;&#245;es entre o PAPI avaliado por PAC e por ecocardiografia (<xref ref-type="fig" rid="f7">Figura 3</xref>). Al&#233;m disso, o PAPI medido via PAC correlacionou-se com a excurs&#227;o sist&#243;lica do plano do anel tric&#250;spide (TAPSE), com r = 0,553 (p &lt; 0,01), e com o strain da parede livre do ventr&#237;culo direito, apresentando coeficiente de correla&#231;&#227;o negativo de r = &#8722;0,344 (p &lt; 0,05). Adicionalmente, observou-se correla&#231;&#227;o positiva entre o PAPI avaliado por PAC e a velocidade sist&#243;lica de pico no anel tric&#250;spide (onda S'), com coeficiente de correla&#231;&#227;o de 0,356 (p &lt; 0,05).</p>
          <fig id="f7">
            <label>Figura 3</label>
            <caption>
              <title>An&#225;lise de correla&#231;&#227;o entre o &#237;ndice de PAPI avaliado por CAP e por ecocardiografia. r = 0,604 (p &lt; 0,05)</title>
            </caption>
            <graphic xlink:href="2675-312X-abcic-39-03-e20260059-0059i-gf04-pt.tif"/></fig>
          <p>Em rela&#231;&#227;o &#224; LVOT-VTI, al&#233;m da correla&#231;&#227;o anteriormente mencionada com a CPO derivada do PAC, foi observada uma correla&#231;&#227;o entre a LVOT-VTI e o DC medido por PAC (r = 0,538; p &lt; 0,01), bem como com o &#237;ndice card&#237;aco medido por PAC (r = 0,542, p &lt; 0,01).</p>
        </sec>
        <sec>
          <title>An&#225;lise de sensibilidade</title>
          <p>Foi realizada uma an&#225;lise de sensibilidade para avaliar a popula&#231;&#227;o que recebia suporte inotr&#243;pico. A correla&#231;&#227;o entre a CPO invasiva e a CPO ecocardiogr&#225;fica foi maior nesse subgrupo em compara&#231;&#227;o com a popula&#231;&#227;o geral: r = 0,812 (p = 0,008). Tamb&#233;m foi realizada uma an&#225;lise de sensibilidade em pacientes com CPO &lt; 0,6 W. Nesse subgrupo, a correla&#231;&#227;o entre a CPO invasiva e a CPO ecocardiogr&#225;fica foi de r = 0,704 (p = 0,005). Em ambos os grupos, n&#227;o foi poss&#237;vel avaliar a correla&#231;&#227;o entre o PAPI invasivo e o PAPI ecocardiogr&#225;fico, uma vez que a medi&#231;&#227;o n&#227;o invasiva do PAPI foi vi&#225;vel em apenas 3 dos 9 pacientes inclu&#237;dos neste subgrupo.</p>
        </sec>
      </sec>
      <sec sec-type="discussion">
        <title>Discuss&#227;o</title>
        <p>A avalia&#231;&#227;o da correla&#231;&#227;o entre medidas hemodin&#226;micas invasivas e n&#227;o invasivas visa identificar par&#226;metros ecocardiogr&#225;ficos que reflitam de forma confi&#225;vel vari&#225;veis hemodin&#226;micas com significado progn&#243;stico, como CPO e PAPI. Essa abordagem pretende oferecer uma estrat&#233;gia diagn&#243;stica mais pr&#225;tica e segura para pacientes com IC avan&#231;ada, minimizando o tempo de avalia&#231;&#227;o e os riscos associados a procedimentos invasivos.</p>
        <p>Conforme relatado por Burstein et al. em um estudo de coorte retrospectivo, a CPO n&#227;o invasiva demonstrou valor progn&#243;stico em pacientes admitidos em unidades de terapia intensiva cardiol&#243;gica. O estudo analisou cerca de 5.000 pacientes, sendo que 50% apresentavam IC descompensada. Valores de CPO abaixo de 0,89 &#177; 0,37 W associaram-se a uma maior mortalidade hospitalar.<sup><xref ref-type="bibr" rid="B16">16</xref></sup> O PAPI ecocardiogr&#225;fico tamb&#233;m demonstrou valor progn&#243;stico, associando-se &#224; mortalidade em 60 dias em casos de CC relacionado &#224; IC aguda descompensada (raz&#227;o de risco 2,96; intervalo de confian&#231;a de 95% 1,23&#8211;7,17; p = 0,02).<sup><xref ref-type="bibr" rid="B12">12</xref></sup> O LVOT-VTI, conforme demonstrado por Jentzer et al. e Machado et al., tamb&#233;m apresentou valor progn&#243;stico significativo entre pacientes com doen&#231;as cardiovasculares, incluindo aqueles com IC e infarto agudo do mioc&#225;rdio.<sup><xref ref-type="bibr" rid="B9">9</xref>,<xref ref-type="bibr" rid="B17">17</xref></sup></p>
        <p>Em rela&#231;&#227;o aos par&#226;metros de fun&#231;&#227;o ventricular esquerda, em nosso estudo, a CPO medida de forma invasiva e a CPO estimada por ecocardiografia apresentaram a correla&#231;&#227;o mais forte. Essa associa&#231;&#227;o foi ainda mais pronunciada no subgrupo de pacientes que recebiam suporte inotr&#243;pico. Al&#233;m disso, a CPO medida via CAP tamb&#233;m demonstrou correla&#231;&#227;o com o DC avaliado por ecocardiografia, bem como com a LVOT-VTI e a fra&#231;&#227;o de eje&#231;&#227;o do ventr&#237;culo esquerdo.</p>
        <p>Quanto ao PAPI, os resultados revelaram uma correla&#231;&#227;o entre sua medida invasiva via CAP e sua estimativa ecocardiogr&#225;fica, bem como com a TAPSE. As correla&#231;&#245;es entre o PAPI e a velocidade da onda S&#8217; e entre PAPI e o strain da parede livre do ventr&#237;culo direito foram mais fracas. Com base na revis&#227;o da literatura, este &#233;, at&#233; onde sabemos, o primeiro estudo a avaliar as correla&#231;&#245;es entre CPO e PAPI invasivos e ecocardiogr&#225;ficos em pacientes com ICFER.</p>
        <p>Stein et al. e Temporelli et al. relataram uma forte correla&#231;&#227;o entre medidas hemodin&#226;micas invasivas e ecocardiogr&#225;ficas em pacientes com IC cr&#244;nica; no entanto, CPO, PAPI e LVOT-VTI n&#227;o foram inclu&#237;dos entre as vari&#225;veis analisadas nesses estudos.<sup><xref ref-type="bibr" rid="B13">13</xref>,<xref ref-type="bibr" rid="B14">14</xref></sup> Frea et al.<sup><xref ref-type="bibr" rid="B12">12</xref></sup> publicaram o maior estudo realizado at&#233; o momento investigando a correla&#231;&#227;o entre par&#226;metros hemodin&#226;micos invasivos e ecocardiogr&#225;ficos no CC.<sup><xref ref-type="bibr" rid="B9">9</xref></sup> A popula&#231;&#227;o do estudo consistia em pacientes com CC secund&#225;rio a IC descompensada. Em nossa coorte, 26,5% dos pacientes recebiam suporte inotr&#243;pico e foram classificados como portadores de IC com perfil INTERMACS III. Embora nossa popula&#231;&#227;o apresentasse n&#237;veis normais de lactato e n&#227;o estivesse em uso de terapia vasopressora no momento da avalia&#231;&#227;o, essas duas popula&#231;&#245;es podem compartilhar condi&#231;&#245;es fisiopatol&#243;gicas semelhantes. No estudo de Frea et al.,<sup><xref ref-type="bibr" rid="B12">12</xref></sup> a correla&#231;&#227;o entre os dois m&#233;todos mostrou um coeficiente de Pearson r = 0,82 (p &lt; 0,001) para a CPO. Os resultados do nosso estudo foram consistentes com esses achados, especialmente entre os pacientes classificados como INTERMACS III, visto que a CPO medida por CAP e ecocardiografia apresentou a correla&#231;&#227;o mais forte entre os dois m&#233;todos em nossa popula&#231;&#227;o (r = 0,73; p &lt; 0,001), sendo ainda mais forte nos pacientes que recebiam suporte inotr&#243;pico (r = 0,81; p = 0,008). Nosso estudo reafirma a for&#231;a da correla&#231;&#227;o entre a CPO invasiva e a CPO ecocardiogr&#225;fica, bem como sua reprodutibilidade, estendendo os achados observados no CC para pacientes com ICFER cr&#244;nica e agudamente descompensada.</p>
        <p>Frea et al.<sup><xref ref-type="bibr" rid="B12">12</xref></sup> tamb&#233;m demonstraram uma forte correla&#231;&#227;o entre o PAPI invasivo e o PAPI ecocardiogr&#225;fico. Uma diferen&#231;a not&#225;vel entre os dois estudos reside na reprodutibilidade do PAPI ecocardiogr&#225;fico. No estudo citado, a estimativa do PAPI foi vi&#225;vel em 97 de 101 pacientes, enquanto em nosso estudo foi poss&#237;vel em apenas 16 de 34 pacientes. A regurgita&#231;&#227;o pulmonar &#233; um achado ecocardiogr&#225;fico raro em pacientes com hipertens&#227;o pulmonar, o que reduz a acur&#225;cia de m&#233;todos que avaliam medidas derivadas dela.<sup><xref ref-type="bibr" rid="B18">18</xref></sup> Existe tamb&#233;m uma variabilidade significativa nos pontos de corte do PAPI derivado do CAP capazes de prever desfechos adversos entre as diferentes popula&#231;&#245;es estudadas. Consequentemente, os valores de corte do PAPI diferem entre CC e IC.<sup><xref ref-type="bibr" rid="B19">19</xref>,<xref ref-type="bibr" rid="B20">20</xref></sup> Por esse motivo, a baixa sensibilidade da regurgita&#231;&#227;o pulmonar e a distin&#231;&#227;o nos limiares de PAPI entre diferentes popula&#231;&#245;es podem ter contribu&#237;do para as diferen&#231;as de reprodutibilidade observadas entre os dois estudos. Portanto, com base em nossos achados, conclu&#237;mos que o PAPI ecocardiogr&#225;fico pode n&#227;o ser um par&#226;metro diagn&#243;stico confi&#225;vel em pacientes com IC cr&#244;nica e agudamente descompensada, devido &#224; sua baixa reprodutibilidade.</p>
        <p>O presente estudo apresenta algumas limita&#231;&#245;es. Em primeiro lugar, o tamanho da popula&#231;&#227;o analisada &#233; um aspecto significativo a ser enfatizado, especialmente ap&#243;s a publica&#231;&#227;o de Frea et al.,<sup><xref ref-type="bibr" rid="B12">12</xref></sup> que ocorreu durante a fase final de recrutamento do nosso estudo. Al&#233;m disso, a heterogeneidade da nossa coorte representa outra limita&#231;&#227;o, visto que o nosso estudo inclui indiv&#237;duos com diversas condi&#231;&#245;es hemodin&#226;micas e diferentes necessidades de suporte terap&#234;utico. Para reduzir a heterogeneidade da popula&#231;&#227;o, realizamos uma an&#225;lise de sensibilidade entre os pacientes que receberam suporte inotr&#243;pico, tentando excluir aqueles com doen&#231;a menos grave. A impossibilidade de obter o PAPI ecocardiogr&#225;fico em parte da amostra representa outra limita&#231;&#227;o. Por fim, o intervalo prolongado entre os dois m&#233;todos de avalia&#231;&#227;o tamb&#233;m pode ser considerado uma limita&#231;&#227;o potencial.</p>
      </sec>
      <sec sec-type="conclusions">
        <title>Conclus&#227;o</title>
        <p>O presente estudo demonstrou correla&#231;&#245;es significativas entre medidas hemodin&#226;micas invasivas e n&#227;o invasivas em pacientes com ICFER, particularmente para par&#226;metros progn&#243;sticos como CPO, PAPI e LVOT-VTI. A CPO apresentou a correla&#231;&#227;o mais forte entre os m&#233;todos, especialmente em pacientes sob suporte inotr&#243;pico. Embora o PAPI tenha apresentado correla&#231;&#227;o entre as t&#233;cnicas, sua reprodutibilidade limitada na ecocardiografia reduz sua utilidade cl&#237;nica nessa popula&#231;&#227;o.</p>
      </sec>
    </body>
    <back>
      <fn-group>
        <fn fn-type="supported-by" id="fn5">
          <label>Fontes de Financiamento</label>
          <p>O presente estudo foi financiado pelo Fundo de Incentivo &#224; Pesquisa (FIPE).</p>
        </fn>
        <fn fn-type="other" id="fn6">
          <label>Vincula&#231;&#227;o Acad&#234;mica</label>
          <p>Este artigo &#233; parte da disserta&#231;&#227;o de Mestrado de Jo&#227;o Pedro da Rosa Barbato pela Universidade Federal do Rio Grande do Sul.</p>
        </fn>
        <fn fn-type="other" id="fn7">
          <label>Aprova&#231;&#227;o &#201;tica e Consentimento Informado</label>
          <p>Este estudo foi aprovado pelo Comit&#234; de &#201;tica do Hospital de Cl&#237;nicas de Porto Alegre, sob o n&#250;mero de protocolo 5920490. Todos os procedimentos envolvidos nesse estudo est&#227;o de acordo com a Declara&#231;&#227;o de Helsinki de 1975, atualizada em 2013. O consentimento informado foi obtido de todos os participantes inclu&#237;dos no estudo.</p>
        </fn>
        <fn fn-type="other" id="fn8">
          <label>Uso de Intelig&#234;ncia Artificial</label>
          <p>Os autores n&#227;o utilizaram ferramentas de intelig&#234;ncia artificial no desenvolvimento deste trabalho.</p>
        </fn>
      </fn-group>
      <sec sec-type="data-availability" specific-use="data-in-article">
        <title>Disponibilidade de Dados</title>
        <p>Os conte&#250;dos subjacentes ao texto da pesquisa est&#227;o contidos no manuscrito.</p>
      </sec>
      <sec id="sec2" sec-type="supplementary-material">
        <title>*Material suplementar</title>
        <supplementary-material id="suppl2">
          <label>Material suplementar</label>
          <media mime-subtype="pdf" mimetype="application" xlink:href="https://minio.scielo.br/documentstore/2675-312X/VMHGNLDwVpYDWXsCdrbwNWs/c93ba0144c44ab2f5ea246ad94eac35d7fac8ebf.pdf"/>
          <p>Para informa&#231;&#227;o adicional, por favor, <ext-link ext-link-type="uri" xlink:href="http://abcimaging.org/supplementary-material/2026/3903/ABCImag-2026-0059_AO_Material-Suplementar.pdf">clique aqui</ext-link>.</p>
        </supplementary-material>
      </sec>
    </back>
  </sub-article>
</article>
