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<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" article-type="case-report" dtd-version="1.1" specific-use="sps-1.8" xml:lang="en">
  <front>
    <journal-meta>
      <journal-id journal-id-type="nlm-ta">Arq Bras Cardiol</journal-id>
      <journal-id journal-id-type="publisher-id">abc</journal-id>
      <journal-title-group>
        <journal-title>Arquivos Brasileiros de Cardiologia</journal-title>
        <abbrev-journal-title abbrev-type="publisher">Arq. Bras. Cardiol.</abbrev-journal-title>
      </journal-title-group>
      <issn pub-type="ppub">0066-782X</issn>
      <issn pub-type="epub">1678-4170</issn>
      <publisher>
        <publisher-name>Sociedade Brasileira de Cardiologia - SBC</publisher-name>
      </publisher>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="publisher-id" specific-use="scielo-v3">qnrSDkDCr6ctbBkDmbBRG4J</article-id>
      <article-id pub-id-type="publisher-id" specific-use="scielo-v2">S0066-782X2018001500430</article-id>
      <article-id pub-id-type="doi">10.5935/abc.20180179</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Case Report</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Partial Papillary Muscle Rupture after Myocardial Infarction and Early Severe Obstructive Bioprosthetic Valve Thrombosis: an Unusual Combination</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Silveira</surname>
            <given-names>In&#234;s</given-names>
          </name>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="corresp" rid="c1"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Oliveira</surname>
            <given-names>Marta</given-names>
          </name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Gomes</surname>
            <given-names>Catarina</given-names>
          </name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Cabral</surname>
            <given-names>Sofia</given-names>
          </name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Luz</surname>
            <given-names>Andr&#233;</given-names>
          </name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Torres</surname>
            <given-names>Severo</given-names>
          </name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff1">
          <label>1</label>
          <institution content-type="orgname">Centro Hospitalar do Porto</institution>
          <addr-line>
            <city>Porto</city>
          </addr-line>
          <country country="PT">Portugal</country>
          <institution content-type="original">Centro Hospitalar do Porto, Porto - Portugal</institution>
        </aff>
      </contrib-group>
      <author-notes>
        <corresp id="c1"><bold>Mailing Address: In&#234;s Silveira</bold>, Largo Prof. Abel Salazar, 4099-001 Porto - Portugal. E-mail: <email>Ines.c.silveira@gmail.com</email></corresp>
        <fn fn-type="con">
          <p>
            <bold>Author contributions</bold>
          </p>
          <p>Conception and design of the research: Silveira I, Oliveira M; Writing of the manuscript: Silveira I, Oliveira M, Gomes C; Critical revision of the manuscript for intellectual content: Gomes C, Cabral S, Luz A, Torres S.</p>
        </fn>
        <fn fn-type="conflict">
          <p>
            <bold>Potential Conflict of Interest</bold>
          </p>
          <p>No potential conflict of interest relevant to this article was reported.</p>
        </fn>
      </author-notes>
      <pub-date pub-type="epub-ppub">
        <month>09</month>
        <year>2018</year>
      </pub-date>
      <volume>111</volume>
      <issue>3</issue>
      <fpage>430</fpage>
      <lpage>433</lpage>
      <history>
        <date date-type="received">
          <day>02</day>
          <month>12</month>
          <year>2017</year>
        </date>
        <date date-type="rev-recd">
          <day>04</day>
          <month>04</month>
          <year>2018</year>
        </date>
        <date date-type="accepted">
          <day>25</day>
          <month>04</month>
          <year>2018</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, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.</license-p>
        </license>
      </permissions>
      <kwd-group xml:lang="en">
        <title>Keywords:</title>
        <kwd>Myocardial Infarction/complications</kwd>
        <kwd>Thrombolytic Therapy</kwd>
        <kwd>Atrioventricular Block/complications</kwd>
        <kwd>Pacemaker Artificial</kwd>
        <kwd>Heart Arrest</kwd>
        <kwd>Heart Rupture</kwd>
        <kwd>Post-Infarction</kwd>
        <kwd>Bioprosthesis</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec sec-type="intro">
      <title>Introduction</title>
      <p>Mechanical complications after myocardial infarction (MI) have become uncommon since the introduction of primary angioplasty.<xref ref-type="bibr" rid="B1">1</xref> They can lead to a rapid clinical deterioration and a fatal outcome, with patient's survival being depen&#173;dent on their prompt recognition and intervention. We describe a case of two rare mechanical complications: a partial papillary muscle rupture after MI, followed by an early severe obstructive thrombosis of the implanted bioprosthetic valve.</p>
      <sec>
        <title>Case report</title>
        <p>We report a case of a 70 year-old male, with a history of dyslipidaemia and smoking habits, who suffered an inferior ST elevation myocardial infarction (STEMI). Given the impossibility to achieve a timely percutaneous coronary artery intervention, thrombolysis was performed within 4 hours of symptoms onset. Advanced atrioventricular block requiring a transcutaneous pacemaker occurred soon after, followed by cardiorespiratory arrest in ventricular fibrillation, which was reversed after one cycle of advanced life support. The patient was transported by airplane to a percutaneous coronary intervention (PCI)-capable centre. Coronary angiography showed a 50-60% stenosis in the proximal segment of the right coronary artery, which was treated with a bare metal stent. Echocardiography showed a moderate left ventricular systolic dysfunction (estimated ejection fraction of 35%), with inferior, inferolateral and inferoseptal akinesia and moderate mitral regurgitation. On the fifth day, the patient was transferred to our centre, after a 10-hour flight. On admission to intensive care unit, the patient was in cardiogenic shock with inotropes and non-invasive ventilation. A bedside transthoracic echocardiography revealed a severe mitral valve regurgitation of uncertain mechanism, along with moderate left ventricle systolic dysfunction and right ventricle systolic compromise. Additional characterisation by transoesophageal echocardiography revealed a 9 mm disruption of the posteromedial papillary muscle consistent with a contained, albeit morphologically imminent, rupture. The instability of the sub-valvular apparatus, leading to a broad posterior leaflet prolapse, caused severe mitral regurgitation with an eccentric jet with Coanda effect, reaching the left atria roof (<xref ref-type="fig" rid="f1">Figure 1</xref>). The patient underwent urgent mitral valve replacement with a biological prosthetic valve (St. Jude #29), with preservation of anterior and posterior leaflets. The patient experienced a favourable post-operative recovery and was discharged 12 days after surgery with anticoagulant therapy for three months, in addition to dual antiplatelet therapy. On the fourth month after surgery, the patient initiated progressive heart failure symptoms (NYHA class III) without any further complaints. Additional transthoracic and transoesophageal evaluations were performed, revealing a significant restriction of the prosthetic mitral valve leaflets mobility due to thrombotic material deposition, leading to severe obstruction, with a mean gradient of 19 mmHg and an effective orifice area estimated by PISA method of 0.4 cm.<xref ref-type="bibr" rid="B2">2</xref> Additionally, in continuity with the prosthesis, a large mural thrombus was present covering the left atrial posteroseptal wall (<xref ref-type="fig" rid="f2">Figure 2</xref>). Urgent surgery, within twenty-four hours after diagnosis, was performed involving mitral bioprosthesis replacement with another biologic prosthesis with significant improvement in clinical status. After an extensive study, no evidence was found of atrial fibrillation or thrombotic disorders. Pathology examination of the excised prosthetic material confirmed prosthetic thrombosis, with no signs of endocarditis.</p>
        <p>
          <fig id="f1">
            <label>Figure 1</label>
            <caption>
              <title>Transoesophageal echocardiogram two-chamber view showing a 9 mm disruption of the posteromedial papillary muscle (pointed with an arrow) consistent with a contained, but morphologically imminent rupture, leading to a broad posterior leaflet prolapse and a severe mitral regurgitation with an eccentric jet. LA: Left Atria; LV: Left Ventricle.</title>
            </caption>
            <graphic xlink:href="1678-4170-abc-111-03-0430-80179-gf01.jpg"/></fig>
        </p>
        <p>
          <fig id="f2">
            <label>Figure 2</label>
            <caption>
              <title>Transoesophageal echocardiogram long axis view and 3D zoom on face view of the mitral valve presenting a significant thickening of mitral bioprosthetic cusps due to thrombotic material deposition, leading to severe obstruction of the prosthetic valve and a large mural thrombus covering the left atrial posteroseptal wall (pointed with an arrow). BPMV: Bioprosthetic Mitral Valve; LA: Left Atria; LV: Left Ventricle.</title>
            </caption>
            <graphic xlink:href="1678-4170-abc-111-03-0430-80179-gf02.jpg"/></fig>
        </p>
      </sec>
    </sec>
    <sec sec-type="discussion">
      <title>Discussion</title>
      <p>In the current era of early mechanical reperfusion, the incidence of papillary muscle rupture (PMR) after MI has decreased, being less than 0.5%. Although rare, complete or partial PMR is a serious complication which can lead to rapid clinical deterioration and death.<xref ref-type="bibr" rid="B1">1</xref><sup>,</sup><xref ref-type="bibr" rid="B2">2</xref> A great deal of foresight is essential for an early recognition of this condition, especially in uncommon scenarios, like the case reported. Moreover, the patient was submitted to thrombolytic therapy and prolonged air travel in the acute phase of MI, which could have contributed to additional ischemia and injury.</p>
      <p>Transthoracic echocardiography (TTE) is of critical importance in the evaluation of patients in cardiogenic shock after MI, and so it is the ini&#173;tial imaging modality used. It has a sensitivity of 65-85% for the diagnosis of PMR.<xref ref-type="bibr" rid="B3">3</xref> However, in some cases TTE is insufficient to accurately ascertain the mechanism causing mitral regurgitation, so an additional characterization with transoesophageal echocardiogram (TEE) becomes crucial to establish diagnosis. TEE can offer superior visibility and characterization of the posterior structures - such as mitral valve apparatus - with a diagnostic yield between 95% and 100%.<xref ref-type="bibr" rid="B4">4</xref><sup>,</sup><xref ref-type="bibr" rid="B5">5</xref> Although partial PMR may be more difficult to identify than complete rupture, it should always be closely investigated in the setting of a flail/prolapse mitral leaflet.<xref ref-type="bibr" rid="B5">5</xref> In our case, only TEE evaluation provided a full characterisation of mitral valve structure and an accurate identification of the mitral valve apparatus disarray. Due to the adverse hemodynamic complications associated with PMR, emergent identification and treatment are essential to improve patient outcomes. The natural history of post-MI PMR is extremely unfavourable under medical treatment alone.<xref ref-type="bibr" rid="B6">6</xref> Partial PMR is also considered a surgical emergency as most of the cases will progress to complete rupture.<xref ref-type="bibr" rid="B7">7</xref> In our case, the instability of the sub-valvular apparatus was notorious with potential imminent complete rupture, as can be seen in <xref ref-type="fig" rid="f1">Figure 1</xref>.</p>
      <p>Bioprosthetic valves are advantageous over mechanical ones due to their comparatively lower incidence of thromboembolic events and avoidance of long-term anticoagulation. Clinically significant bioprosthetic valve thrombosis (BPVT) is considered a rare phenomenon, however accumulated evidence suggests that it is an under-recognised complication.<xref ref-type="bibr" rid="B8">8</xref> Its diagnosis remains challenging due to a general lack of awareness on this condition. A combination of clinical and echocardiographic features is helpful for diagnosis. Specific predisposing factors to BPVT include low cardiac output, left atrial dilatation, prior history of thromboembolic events, atrial fibrillation and hypercoagulability. New-onset acute heart failure symptoms, progressive dyspnoea, new thromboembolic event and regression of heart failure symptoms with anticoagulation therapy should be considered as flags for this condition. Some echocardiographic features support the diagnosis of BPVT, such as: direct visualisation of valve thrombosis, like the reported case; a 50% mean gradient increase compared with post-operative evaluation; increased cusp thickness (&gt;2 mm), especially on the downstream aspect of the BPV; abnormal leaflet mobility; regression of BPV abnormalities with anticoagulation, usually within 1-3 months of its initiation or reduced leaflet motion in a cardiac CT scan.<xref ref-type="bibr" rid="B8">8</xref><sup>,</sup><xref ref-type="bibr" rid="B9">9</xref> The optimal treatment of BPVT remains a matter of debate. The strategy depends on clinical presentation, patient's hemodynamic status, presence of BPV obstruction and valve location. Conventional treatment options include surgery, fibrinolysis and anticoagulation, but anticoagulation coupled with surgery remains the mainstay of treatment.<xref ref-type="bibr" rid="B10">10</xref> Although independence from long term anticoagulation is an advantage of bioprosthetic valve replacement, cases like the one we described highlight the importance of considering this condition even in patients without significant risk factors, who display heart failure symptoms early after valve replacement. Post-operatively, patients must be categorised according to risk, and perhaps long-term anticoagulation should be considered for high risk patients, as well as periodic echocardiographic evaluation of biological prosthetic valves. In both complications described in this case, echocardiographic characterization with 2D/3D images was essential for the establishment of a correct diagnosis and for guiding treatment.</p>
      <p>This case illustrates two uncommon cardiac mechanical complications, being peculiar their association in the same patient. Despite their distinct pathophysiology, both conditions represent cardiac emergencies requiring a high index of suspicion and an accurate diagnosis. Cardiovascular imaging stands as an extremely valuable supporting technique in a critical-care setting. The precise recognition of the partial papillary muscle rupture (occasionally a missed diagnosis) and the early obstructive bioprosthetic valve thrombosis allowed a prompt and successfully surgical correction of these conditions, with significant impact on patient's health and recovery.</p>
    </sec>
  </body>
  <back>
    <fn-group>
      <fn fn-type="financial-disclosure">
        <p>
          <bold>Sources of Funding</bold>
        </p>
        <p>There were no external funding sources for this study.</p>
      </fn>
      <fn fn-type="other">
        <p>
          <bold>Study Association</bold>
        </p>
        <p>This study is not associated with any thesis or dissertation work.</p>
      </fn>
    </fn-group>
    <ref-list>
      <title>References</title>
      <ref id="B1">
        <label>1</label>
        <mixed-citation>1 Figueras J, Alcalde O, Barrabe&#180;s JA, Serra V, Alguersuari J, Cortadellas J, et al. Changes in hospital mortality rates in 425 patients with acute ST-elevation myocardial infarction and cardiac rupture over a 30-year period. Circulation. 2008;118(25):2783-9.</mixed-citation>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name>
              <surname>Figueras</surname>
              <given-names>J</given-names>
            </name>
            <name>
              <surname>Alcalde</surname>
              <given-names>O</given-names>
            </name>
            <name>
              <surname>Barrabe&#180;s</surname>
              <given-names>JA</given-names>
            </name>
            <name>
              <surname>Serra</surname>
              <given-names>V</given-names>
            </name>
            <name>
              <surname>Alguersuari</surname>
              <given-names>J</given-names>
            </name>
            <name>
              <surname>Cortadellas</surname>
              <given-names>J</given-names>
            </name>
            <etal/>
          </person-group>
          <article-title>Changes in hospital mortality rates in 425 patients with acute ST-elevation myocardial infarction and cardiac rupture over a 30-year period</article-title>
          <source>Circulation</source>
          <year>2008</year>
          <volume>118</volume>
          <issue>25</issue>
          <fpage>2783</fpage>
          <lpage>2789</lpage>
        </element-citation>
      </ref>
      <ref id="B2">
        <label>2</label>
        <mixed-citation>2 Bouma W, Wijdh-den Hamer IJ, Koene BM, Kuijprs M, Natour E, Erasmus ME, et al. Long-term survival after mitral valve surgery for post-myocardial infarction papillary muscle rupture. J Cardiothorac Surg. Jan 27 2015;10:11.</mixed-citation>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name>
              <surname>Bouma</surname>
              <given-names>W</given-names>
            </name>
            <name>
              <surname>Wijdh-den Hamer</surname>
              <given-names>IJ</given-names>
            </name>
            <name>
              <surname>Koene</surname>
              <given-names>BM</given-names>
            </name>
            <name>
              <surname>Kuijprs</surname>
              <given-names>M</given-names>
            </name>
            <name>
              <surname>Natour</surname>
              <given-names>E</given-names>
            </name>
            <name>
              <surname>Erasmus</surname>
              <given-names>ME</given-names>
            </name>
            <etal/>
          </person-group>
          <article-title>Long-term survival after mitral valve surgery for post-myocardial infarction papillary muscle rupture</article-title>
          <source>J Cardiothorac Surg</source>
          <day>27</day>
          <month>1</month>
          <year>2015</year>
          <volume>10</volume>
          <fpage>11</fpage>
          <lpage>11</lpage>
        </element-citation>
      </ref>
      <ref id="B3">
        <label>3</label>
        <mixed-citation>3 Czarnecki A, Thakrar A, Fang T, Lytwyn M, Ahmade R, Pascoe E, et al. Acute severe mitral regurgitation: con&#173;sideration of papillary muscle architecture. Cardiovasc Ultrasound. Jan 18 2008; 6:5.</mixed-citation>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name>
              <surname>Czarnecki</surname>
              <given-names>A</given-names>
            </name>
            <name>
              <surname>Thakrar</surname>
              <given-names>A</given-names>
            </name>
            <name>
              <surname>Fang</surname>
              <given-names>T</given-names>
            </name>
            <name>
              <surname>Lytwyn</surname>
              <given-names>M</given-names>
            </name>
            <name>
              <surname>Ahmade</surname>
              <given-names>R</given-names>
            </name>
            <name>
              <surname>Pascoe</surname>
              <given-names>E</given-names>
            </name>
            <etal/>
          </person-group>
          <article-title>Acute severe mitral regurgitation: con&#173;sideration of papillary muscle architecture</article-title>
          <source>Cardiovasc Ultrasound</source>
          <day>18</day>
          <month>1</month>
          <year>2008</year>
          <volume>6</volume>
          <fpage>5</fpage>
          <lpage>5</lpage>
        </element-citation>
      </ref>
      <ref id="B4">
        <label>4</label>
        <mixed-citation>4 Sochowski RA, Chan KL, Ascah K, Bedard P. Comparison of accuracy of transesophageal versus transthoracic echocardiography for the detection of mitral valve prolapse with ruptured chordae tendinae (flail mitral leaf&#173;let). Am J Cardiol.1991;67(15):1251-5.</mixed-citation>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name>
              <surname>Sochowski</surname>
              <given-names>RA</given-names>
            </name>
            <name>
              <surname>Chan</surname>
              <given-names>KL</given-names>
            </name>
            <name>
              <surname>Ascah</surname>
              <given-names>K</given-names>
            </name>
            <name>
              <surname>Bedard</surname>
              <given-names>P</given-names>
            </name>
          </person-group>
          <article-title>Comparison of accuracy of transesophageal versus transthoracic echocardiography for the detection of mitral valve prolapse with ruptured chordae tendinae (flail mitral leaf&#173;let)</article-title>
          <source>Am J Cardiol</source>
          <year>1991</year>
          <volume>67</volume>
          <issue>15</issue>
          <fpage>1251</fpage>
          <lpage>1255</lpage>
        </element-citation>
      </ref>
      <ref id="B5">
        <label>5</label>
        <mixed-citation>5 Havins J, Lick S, Boor P, Arora H, Ahmad M. Real time three-dimensional transesophageal echocardiography in partial posteromedial papillary muscle rupture. Echocardiography. 2013;30(6):E179-E81.</mixed-citation>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name>
              <surname>Havins</surname>
              <given-names>J</given-names>
            </name>
            <name>
              <surname>Lick</surname>
              <given-names>S</given-names>
            </name>
            <name>
              <surname>Boor</surname>
              <given-names>P</given-names>
            </name>
            <name>
              <surname>Arora</surname>
              <given-names>H</given-names>
            </name>
            <name>
              <surname>Ahmad</surname>
              <given-names>M</given-names>
            </name>
          </person-group>
          <article-title>Real time three-dimensional transesophageal echocardiography in partial posteromedial papillary muscle rupture</article-title>
          <source>Echocardiography</source>
          <year>2013</year>
          <volume>30</volume>
          <issue>6</issue>
          <fpage>E179</fpage>
          <lpage>EE81</lpage>
        </element-citation>
      </ref>
      <ref id="B6">
        <label>6</label>
        <mixed-citation>6 Calvo FE, Figueras J, Cortadellas J, Soler J. Severe mitral regurgitation complicating acute myocardial infarction. Clinical and angiographic differences between patients with and without papillary muscle rupture. Eur Heart J. 1997;18(10):1606-10.</mixed-citation>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name>
              <surname>Calvo</surname>
              <given-names>FE</given-names>
            </name>
            <name>
              <surname>Figueras</surname>
              <given-names>J</given-names>
            </name>
            <name>
              <surname>Cortadellas</surname>
              <given-names>J</given-names>
            </name>
            <name>
              <surname>Soler</surname>
              <given-names>J</given-names>
            </name>
          </person-group>
          <article-title>Severe mitral regurgitation complicating acute myocardial infarction. Clinical and angiographic differences between patients with and without papillary muscle rupture</article-title>
          <source>Eur Heart J</source>
          <year>1997</year>
          <volume>18</volume>
          <issue>10</issue>
          <fpage>1606</fpage>
          <lpage>1610</lpage>
        </element-citation>
      </ref>
      <ref id="B7">
        <label>7</label>
        <mixed-citation>7 Christ G, Siostrzonek P, Maurer G, Baumgartenr H. Partial papillary muscle rupture complicating acute myocardial infarction. Diagnosis by multiplane transoesophageal echocardiography. Eur Heart J. 1995;16(11):1736-8.</mixed-citation>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name>
              <surname>Christ</surname>
              <given-names>G</given-names>
            </name>
            <name>
              <surname>Siostrzonek</surname>
              <given-names>P</given-names>
            </name>
            <name>
              <surname>Maurer</surname>
              <given-names>G</given-names>
            </name>
            <name>
              <surname>Baumgartenr</surname>
              <given-names>H</given-names>
            </name>
          </person-group>
          <article-title>Partial papillary muscle rupture complicating acute myocardial infarction. Diagnosis by multiplane transoesophageal echocardiography</article-title>
          <source>Eur Heart J</source>
          <year>1995</year>
          <volume>16</volume>
          <issue>11</issue>
          <fpage>1736</fpage>
          <lpage>1738</lpage>
        </element-citation>
      </ref>
      <ref id="B8">
        <label>8</label>
        <mixed-citation>8 Oliver JM, Galloge P, Gonzalez A, Dominguez FJ, Gamallo C, Mesa JM. Bioprosthetic mitral valve thrombosis: clinical profile, Transesophageal echocardiographic features, and follow-up after anticoagulant therapy. J Am Soc Echocardiogr. 1996;9(5):691-9.</mixed-citation>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name>
              <surname>Oliver</surname>
              <given-names>JM</given-names>
            </name>
            <name>
              <surname>Galloge</surname>
              <given-names>P</given-names>
            </name>
            <name>
              <surname>Gonzalez</surname>
              <given-names>A</given-names>
            </name>
            <name>
              <surname>Dominguez</surname>
              <given-names>FJ</given-names>
            </name>
            <name>
              <surname>Gamallo</surname>
              <given-names>C</given-names>
            </name>
            <name>
              <surname>Mesa</surname>
              <given-names>JM</given-names>
            </name>
          </person-group>
          <article-title>Bioprosthetic mitral valve thrombosis: clinical profile, Transesophageal echocardiographic features, and follow-up after anticoagulant therapy</article-title>
          <source>J Am Soc Echocardiogr</source>
          <year>1996</year>
          <volume>9</volume>
          <issue>5</issue>
          <fpage>691</fpage>
          <lpage>699</lpage>
        </element-citation>
      </ref>
      <ref id="B9">
        <label>9</label>
        <mixed-citation>9 Egbe AC, Pislaru SV, Pellikka PA, Poterucha JT, Schaff HV, Malozewski JJ, et al. Bioprosthetic valve thrombosis versus structural failure: clinical and echocardiographic predictors. J Am Coll Cardiol. 2015;66(21):2285-94.</mixed-citation>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name>
              <surname>Egbe</surname>
              <given-names>AC</given-names>
            </name>
            <name>
              <surname>Pislaru</surname>
              <given-names>SV</given-names>
            </name>
            <name>
              <surname>Pellikka</surname>
              <given-names>PA</given-names>
            </name>
            <name>
              <surname>Poterucha</surname>
              <given-names>JT</given-names>
            </name>
            <name>
              <surname>Schaff</surname>
              <given-names>HV</given-names>
            </name>
            <name>
              <surname>Malozewski</surname>
              <given-names>JJ</given-names>
            </name>
            <etal/>
          </person-group>
          <article-title>Bioprosthetic valve thrombosis versus structural failure: clinical and echocardiographic predictors</article-title>
          <source>J Am Coll Cardiol</source>
          <year>2015</year>
          <volume>66</volume>
          <issue>21</issue>
          <fpage>2285</fpage>
          <lpage>2294</lpage>
        </element-citation>
      </ref>
      <ref id="B10">
        <label>10</label>
        <mixed-citation>10 Lengyel M, Fuster V, Keltai M, Roudaut R, Schulte HD, Seward JB, et al. Guidelines for management of left-sided prosthetic valve thrombosis: a role for thrombolytic therapy. Consensus conference on prosthetic valve thrombosis. J Am Coll Cardiol. 1997;30(6):1521-6.</mixed-citation>
        <element-citation publication-type="journal">
          <person-group person-group-type="author">
            <name>
              <surname>Lengyel</surname>
              <given-names>M</given-names>
            </name>
            <name>
              <surname>Fuster</surname>
              <given-names>V</given-names>
            </name>
            <name>
              <surname>Keltai</surname>
              <given-names>M</given-names>
            </name>
            <name>
              <surname>Roudaut</surname>
              <given-names>R</given-names>
            </name>
            <name>
              <surname>Schulte</surname>
              <given-names>HD</given-names>
            </name>
            <name>
              <surname>Seward</surname>
              <given-names>JB</given-names>
            </name>
            <etal/>
          </person-group>
          <article-title>Guidelines for management of left-sided prosthetic valve thrombosis: a role for thrombolytic therapy. Consensus conference on prosthetic valve thrombosis</article-title>
          <source>J Am Coll Cardiol</source>
          <year>1997</year>
          <volume>30</volume>
          <issue>6</issue>
          <fpage>1521</fpage>
          <lpage>1526</lpage>
        </element-citation>
      </ref>
    </ref-list>
  </back>
  <sub-article article-type="translation" id="s1" xml:lang="pt">
    <front-stub>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Relato de Caso</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Rutura Parcial de M&#250;sculo Papilar ap&#243;s Infarto do Mioc&#225;rdio e Trombose Obstrutiva Severa Precoce de Biopr&#243;tese valvar: Uma Combina&#231;&#227;o Invulgar</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Silveira</surname>
            <given-names>In&#234;s</given-names>
          </name>
          <xref ref-type="aff" rid="aff2">1</xref>
          <xref ref-type="corresp" rid="c2"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Oliveira</surname>
            <given-names>Marta</given-names>
          </name>
          <xref ref-type="aff" rid="aff2">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Gomes</surname>
            <given-names>Catarina</given-names>
          </name>
          <xref ref-type="aff" rid="aff2">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Cabral</surname>
            <given-names>Sofia</given-names>
          </name>
          <xref ref-type="aff" rid="aff2">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Luz</surname>
            <given-names>Andr&#233;</given-names>
          </name>
          <xref ref-type="aff" rid="aff2">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Torres</surname>
            <given-names>Severo</given-names>
          </name>
          <xref ref-type="aff" rid="aff2">1</xref>
        </contrib>
        <aff id="aff2">
          <label>1</label>
          <institution content-type="original">Centro Hospitalar do Porto, Porto - Portugal</institution>
        </aff>
      </contrib-group>
      <author-notes>
        <corresp id="c2"><bold>Correspond&#234;ncia: In&#234;s Silveira</bold>, Largo Prof. Abel Salazar, 4099-001 Porto - Portugal. E-mail: <email>Ines.c.silveira@gmail.com</email></corresp>
        <fn fn-type="con">
          <p>
            <bold>Contribui&#231;&#227;o dos autores</bold>
          </p>
          <p>Concep&#231;&#227;o e desenho da pesquisa: Silveira I, Oliveira M; Reda&#231;&#227;o do manuscrito: Silveira I, Oliveira M, Gomes C; Revis&#227;o cr&#237;tica do manuscrito quanto ao conte&#250;do intelectual importante: Gomes C, Cabral S, Luz A, Torres S.</p>
        </fn>
        <fn fn-type="conflict">
          <p>
            <bold>Potencial conflito de interesses</bold>
          </p>
          <p>Declaro n&#227;o haver conflito de interesses pertinentes.</p>
        </fn>
      </author-notes>
      <kwd-group xml:lang="pt">
        <title>Palavras-chave:</title>
        <kwd>Infarto do Mioc&#225;rdio/complica&#231;&#245;es</kwd>
        <kwd>Terapia trombol&#237;tica</kwd>
        <kwd>Bloqueio Atriventricular/complica&#231;&#245;es</kwd>
        <kwd>Marcapasso Artificial</kwd>
        <kwd>Parada card&#237;aca</kwd>
        <kwd>Ruptura Card&#237;aca P&#243;s Infarto</kwd>
        <kwd>Biopr&#243;tese</kwd>
      </kwd-group>
    </front-stub>
    <body>
      <sec sec-type="intro">
        <title>Introdu&#231;&#227;o</title>
        <p>Complica&#231;&#245;es mec&#226;nicas ap&#243;s infarto do mioc&#225;rdio (IM) tornaram-se incomuns desde a introdu&#231;&#227;o da angioplastia prim&#225;ria.<xref ref-type="bibr" rid="B1">1</xref> Estas podem levar &#224; deteriora&#231;&#227;o r&#225;pida do quadro cl&#237;nico e a um desfecho fatal, e a sobrevida do paciente depende de identifica&#231;&#227;o e interven&#231;&#227;o imediatos. Este artigo descreve um caso de duas complica&#231;&#245;es mec&#226;nicas raras: uma ruptura parcial do m&#250;sculo papilar ap&#243;s infarto do mioc&#225;rdio, seguida de uma trombose obstrutiva severa precoce de biopr&#243;tese valvar.</p>
        <sec>
          <title>Relato de Caso</title>
          <p>Paciente do sexo masculino, 70 anos, com hist&#243;ria de dislipidemia e tabagismo, que sofreu um infarto do mioc&#225;rdio com supradesnivelamento do segmento ST (IAMCSST) em regi&#227;o inferior. Dada a impossibilidade de uma interven&#231;&#227;o coron&#225;ria percut&#226;nea em tempo &#250;til, foi realizada tromb&#243;lise dentro de 4 horas do in&#237;cio dos sintomas. Logo em seguida, ocorreu bloqueio atrioventricular avan&#231;ado, necessitando de marcapasso transcut&#226;neo, seguido de parada cardiorrespirat&#243;ria em fibrila&#231;&#227;o ventricular, revertida ap&#243;s um ciclo de suporte avan&#231;ado de vida. O paciente foi transportado de avi&#227;o para um centro com interven&#231;&#227;o coron&#225;ria percut&#226;nea (ICP). A angiografia coron&#225;ria mostrou uma estenose de 50-60% no segmento proximal da art&#233;ria coron&#225;ria direita, que foi tratada com stent met&#225;lico. O ecocardiograma mostrou disfun&#231;&#227;o sist&#243;lica moderada do ventr&#237;culo esquerdo (fra&#231;&#227;o de eje&#231;&#227;o estimada de 35%), com acinesia inferior, &#237;nfero-lateral e &#237;nfero-septal, e regurgita&#231;&#227;o mitral moderada. No quinto dia, o paciente foi transferido para o nosso centro, ap&#243;s um v&#244;o de 10 horas. Ao dar entrada na unidade de terapia intensiva, o paciente estava em choque cardiog&#234;nico, sob inotr&#243;picos e ventila&#231;&#227;o n&#227;o invasiva. O ecocardiograma transtor&#225;cico &#224; beira do leito revelou regurgita&#231;&#227;o mitral grave de mecanismo incerto, al&#233;m de disfun&#231;&#227;o sist&#243;lica moderada do ventr&#237;culo esquerdo e comprometimento sist&#243;lico do ventr&#237;culo direito. Caracteriza&#231;&#227;o adicional atrav&#233;s de ecocardiograma transesof&#225;gico revelou uma ruptura de 9 mm do m&#250;sculo papilar posteromedial, consistente com uma ruptura contida, embora morfologicamente iminente. A instabilidade do aparelho subvalvar, que levou a amplo prolapso do folheto posterior, provocou grave regurgita&#231;&#227;o mitral com jato exc&#234;ntrico com efeito Coanda, atingindo o teto do &#225;trio esquerdo (<xref ref-type="fig" rid="f3">Figura 1</xref>). O paciente foi submetido a substitui&#231;&#227;o valvar mitral de urg&#234;ncia por pr&#243;tese biol&#243;gica (St. Jude #29), com preserva&#231;&#227;o dos folhetos anterior e posterior. Teve uma recupera&#231;&#227;o p&#243;s-operat&#243;ria favor&#225;vel e recebeu alta hospitalar 12 dias ap&#243;s a cirurgia, com terapia anticoagulante por tr&#234;s meses, al&#233;m de terapia antiplaquet&#225;ria dupla. No quarto m&#234;s ap&#243;s a cirurgia, o paciente apresentou sintomas de insufici&#234;ncia card&#237;aca progressiva (classe III da NYHA), sem outras queixas. Foram realizadas an&#225;lises transtor&#225;cicas e transesof&#225;gicas adicionais, que revelaram uma restri&#231;&#227;o consider&#225;vel da mobilidade dos folhetos prot&#233;ticos mitrais devido &#224; deposi&#231;&#227;o de material tromb&#243;tico, levando a obstru&#231;&#227;o grave, com um gradiente m&#233;dio de 19 mmHg e uma &#225;rea de orif&#237;cio efetiva estimada pelo m&#233;todo PISA de 0,4 cm<sup>2</sup>.<xref ref-type="bibr" rid="B2">2</xref> Al&#233;m disso, em continuidade com a pr&#243;tese, havia um grande trombo mural cobrindo a parede p&#243;stero-septal do &#225;trio esquerdo (<xref ref-type="fig" rid="f4">Figura 2</xref>). Foi realizada cirurgia de urg&#234;ncia 24 horas ap&#243;s o diagn&#243;stico, envolvendo a substitui&#231;&#227;o da biopr&#243;tese mitral por outra pr&#243;tese biol&#243;gica, com melhora significativa do quadro cl&#237;nico. Ap&#243;s extensa investiga&#231;&#227;o, n&#227;o foram encontradas evid&#234;ncias de fibrila&#231;&#227;o atrial ou dist&#250;rbios tromb&#243;ticos. O exame anatomopatol&#243;gico do material prot&#233;tico ressecado confirmou trombose prost&#233;tica, sem sinais de endocardite.</p>
          <p>
            <fig id="f3">
              <label>Figura 1</label>
              <caption>
                <title>Vis&#227;o de duas c&#226;maras por ecocardiograma transesof&#225;gico mostrando ruptura de 9 mm do m&#250;sculo papilar posteromedeial (apontada com uma seta), consistente com uma ruptura contida, mas morfologicamente iminente, levando a prolapso amplo do folheto posterior e regurgita&#231;&#227;o mitral grave com jato exc&#234;ntrico. AE: &#225;trio esquerdo; VE: ventr&#237;culo esquerdo.</title>
              </caption>
              <graphic xlink:href="1678-4170-abc-111-03-0430-80179-gf01-pt.jpg"/></fig>
          </p>
          <p>
            <fig id="f4">
              <label>Figura 2</label>
              <caption>
                <title>Vis&#227;o do eixo longo e zoom 3D na face da v&#225;lvula mitral por ecocardiograma transesof&#225;gico mostrando espessamento consider&#225;vel da biopr&#243;tese mitral devido &#224; deposi&#231;&#227;o de material tromb&#243;tico, levando a obstru&#231;&#227;o grave da pr&#243;tese valvar e a um grande trombo mural cobrindo a parede p&#243;stero-septal do &#225;trio esquerdo (apontada com uma seta). BPVM: Biopr&#243;tese valvar Mitral; AE: &#225;trio esquerdo; VE: ventr&#237;culo esquerdo.</title>
              </caption>
              <graphic xlink:href="1678-4170-abc-111-03-0430-80179-gf02-pt.jpg"/></fig>
          </p>
        </sec>
      </sec>
      <sec sec-type="discussion">
        <title>Discuss&#227;o</title>
        <p>Na era atual de reperfus&#227;o mec&#226;nica precoce, a incid&#234;ncia de ruptura do m&#250;sculo papilar (RMP) ap&#243;s IM diminuiu, sendo inferior a 0,5%. Embora rara, a RMP completa ou parcial &#233; uma complica&#231;&#227;o grave que pode levar &#224; deteriora&#231;&#227;o r&#225;pida do quadro cl&#237;nico e a &#243;bito.<xref ref-type="bibr" rid="B1">1</xref><sup>,</sup><xref ref-type="bibr" rid="B2">2</xref> Uma grande prud&#234;ncia &#233; essencial para a identifica&#231;&#227;o precoce dessa condi&#231;&#227;o, especialmente em cen&#225;rios incomuns, como no caso relatado. Al&#233;m disso, o paciente foi submetido a terapia trombol&#237;tica e a transporte a&#233;reo prolongado na fase aguda do infarto do mioc&#225;rdio, o que poderia ter contribu&#237;do para isquemia e les&#245;es adicionais.</p>
        <p>A ecocardiografia transtor&#225;cica (ETT) &#233; fundamental na avalia&#231;&#227;o de pacientes em choque cardiog&#234;nico ap&#243;s IM, sendo por isso a modalidade inicial de imagiologia utilizada. Sua sensibilidade para o diagn&#243;stico de RMP &#233; de 65 a 85%.<xref ref-type="bibr" rid="B3">3</xref> No entanto, em alguns casos, o ETT &#233; insuficiente para determinar o mecanismo causador da regurgita&#231;&#227;o mitral com precis&#227;o; por isso, torna-se crucial obter uma caracteriza&#231;&#227;o adicional com o ecocardiograma transesof&#225;gico (ETE) para estabelecer o diagn&#243;stico. O ETE pode oferecer maior visibilidade e caracteriza&#231;&#227;o das estruturas posteriores - como o aparelho valvar mitral - com rendimento diagn&#243;stico entre 95% e 100%.<xref ref-type="bibr" rid="B4">4</xref><sup>,</sup><xref ref-type="bibr" rid="B5">5</xref> Embora a RMP parcial possa ser mais dif&#237;cil de identificar do que a completa, deve sempre ser investigada cuidadosamente no contexto de um prolapso do folheto mitral.<xref ref-type="bibr" rid="B5">5</xref> No caso aqui apresentado, somente a avalia&#231;&#227;o do ETE forneceu caracteriza&#231;&#227;o completa da estrutura da v&#225;lvula mitral e identifica&#231;&#227;o precisa do desarranjo do aparelho valvar mitral. Devido &#224;s complica&#231;&#245;es hemodin&#226;micas adversas associadas &#224; RMP, a identifica&#231;&#227;o e tratamento imediatos s&#227;o essenciais para um desfecho favor&#225;vel do paciente. A evolu&#231;&#227;o natural do RMP p&#243;s-IM &#233; extremamente desfavor&#225;vel somente sob tratamento m&#233;dico.<xref ref-type="bibr" rid="B6">6</xref> A RMP parcial tamb&#233;m &#233; considerada uma emerg&#234;ncia cir&#250;rgica, pois a maioria dos casos evolui para ruptura completa.<xref ref-type="bibr" rid="B7">7</xref> No caso sob estudo, a instabilidade do aparelho subvalvar foi not&#243;ria, com ruptura completa potencial e iminente, como pode ser visto na <xref ref-type="fig" rid="f3">Figura 1</xref>.</p>
        <p>As v&#225;lvulas bioprot&#233;ticas s&#227;o vantajosas em rela&#231;&#227;o &#224;s mec&#226;nicas devido &#224; sua menor incid&#234;ncia de eventos tromboemb&#243;licos e &#224; aus&#234;ncia da anticoagula&#231;&#227;o a longo prazo. A trombose de biopr&#243;tese valvar (TBPV) clinicamente significativa &#233; considerada um fen&#244;meno raro, por&#233;m acumula-se evid&#234;ncia que sugere ser uma complica&#231;&#227;o pouco identificada.<xref ref-type="bibr" rid="B8">8</xref> Seu diagn&#243;stico ainda &#233; um desafio devido &#224; falta geral de conscientiza&#231;&#227;o sobre essa condi&#231;&#227;o. A combina&#231;&#227;o de caracter&#237;sticas cl&#237;nicas e ecocardiogr&#225;ficas &#233; &#250;til para seu diagn&#243;stico. Fatores predisponentes espec&#237;ficos para a TBPV incluem baixo d&#233;bito card&#237;aco, dilata&#231;&#227;o atrial esquerda, hist&#243;ria pr&#233;via de eventos tromboemb&#243;licos, fibrila&#231;&#227;o atrial e hipercoagulabilidade. Sintomas de insufici&#234;ncia card&#237;aca aguda de in&#237;cio recente, dispneia progressiva, novo evento tromboemb&#243;lico e regress&#227;o dos sintomas de insufici&#234;ncia card&#237;aca sob terapia de anticoagula&#231;&#227;o devem ser considerados como indicadores desta condi&#231;&#227;o. Algumas caracter&#237;sticas ecocardiogr&#225;ficas refor&#231;am o diagn&#243;stico de TBPV, como: visualiza&#231;&#227;o direta de trombose valvar, como no caso relatado; aumento de gradiente m&#233;dio de 50% em compara&#231;&#227;o com a avalia&#231;&#227;o p&#243;s-operat&#243;ria; espessura da c&#250;spide aumentada (&gt; 2 mm), principalmente no aspecto a jusante da BPV; mobilidade anormal dos folhetos; regress&#227;o das anormalidades do BPV com anticoagula&#231;&#227;o, geralmente dentro de um a tr&#234;s meses ap&#243;s o in&#237;cio ou movimentos reduzidos dos folhetos em tomografia computadorizada card&#237;aca.<xref ref-type="bibr" rid="B8">8</xref><sup>,</sup><xref ref-type="bibr" rid="B9">9</xref> O tratamento ideal da TBPV continua a ser objeto de debate. A estrat&#233;gia depende da apresenta&#231;&#227;o cl&#237;nica, do estado hemodin&#226;mico do paciente, da presen&#231;a de obstru&#231;&#227;o &#224; biopr&#243;tese valvar (BPV) e da localiza&#231;&#227;o da v&#225;lvula. As op&#231;&#245;es convencionais de tratamento incluem cirurgia, fibrin&#243;lise e anticoagula&#231;&#227;o, mas a base do tratamento continua sendo a anticoagula&#231;&#227;o associada &#224; cirurgia.<xref ref-type="bibr" rid="B10">10</xref> Embora a independ&#234;ncia da anticoagula&#231;&#227;o de longo prazo seja uma vantagem da substitui&#231;&#227;o valvar bioprot&#233;tica, casos como o descrito aqui destacam a import&#226;ncia de se considerar essa condi&#231;&#227;o mesmo em pacientes sem fatores de risco consider&#225;veis, que apresentam sintomas de insufici&#234;ncia card&#237;aca precocemente ap&#243;s a troca valvar. No p&#243;s-operat&#243;rio, os pacientes devem ser categorizados de acordo com o risco, e talvez a anticoagula&#231;&#227;o a longo prazo deva ser considerada para pacientes de alto risco, bem como a avalia&#231;&#227;o ecocardiogr&#225;fica peri&#243;dica de pr&#243;teses biol&#243;gicas. Em ambas as complica&#231;&#245;es descritas neste caso, a caracteriza&#231;&#227;o ecocardiogr&#225;fica com imagens 2D/3D foi essencial para definir um diagn&#243;stico correto e orientar o tratamento.</p>
        <p>Este caso ilustra duas complica&#231;&#245;es mec&#226;nicas card&#237;acas incomuns, sendo peculiar sua associa&#231;&#227;o no mesmo paciente. Apesar das fisiopatologias distintas, ambas as condi&#231;&#245;es representam emerg&#234;ncias card&#237;acas que exigem alto &#237;ndice de suspeita e diagn&#243;stico preciso. A imagiologia cardiovascular &#233; uma t&#233;cnica de apoio extremamente valiosa numa situa&#231;&#227;o de cuidados cr&#237;ticos. A identifica&#231;&#227;o precisa da ruptura parcial do m&#250;sculo papilar (ocasionalmente um diagn&#243;stico despercebido) e da trombose obstrutiva precoce da biopr&#243;tese valvar permitiram uma corre&#231;&#227;o cir&#250;rgica r&#225;pida e bem-sucedida dessas condi&#231;&#245;es, com impacto significativo na sa&#250;de e na recupera&#231;&#227;o do paciente.</p>
      </sec>
    </body>
    <back>
      <fn-group>
        <fn fn-type="financial-disclosure">
          <p>
            <bold>Fontes de financiamento</bold>
          </p>
          <p>O presente estudo n&#227;o teve fontes de financiamento externas.</p>
        </fn>
        <fn fn-type="other">
          <p>
            <bold>Vincula&#231;&#227;o acad&#234;mica</bold>
          </p>
          <p>N&#227;o h&#225; vincula&#231;&#227;o deste estudo a programas de p&#243;s-gradua&#231;&#227;o.</p>
        </fn>
      </fn-group>
    </back>
  </sub-article>
</article>
