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<article article-type="case-report" dtd-version="1.1" specific-use="sps-1.9" xml:lang="en" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">
	<front>
		<journal-meta>
			<journal-id journal-id-type="publisher-id">dic</journal-id>
			<journal-title-group>
				<journal-title>ABC Imagem Cardiovascular</journal-title>
				<abbrev-journal-title abbrev-type="publisher">Arq Bras Cardiol: Imagem cardiovasc.</abbrev-journal-title>
			</journal-title-group>
			<issn pub-type="epub">2675-312X</issn>
			<publisher>
				<publisher-name>Sociedade Brasileira de Cardiologia</publisher-name>
			</publisher>
		</journal-meta>
		<article-meta>
			<article-id pub-id-type="doi">10.36660/abcimg.2023361i</article-id>
			<article-categories>
				<subj-group subj-group-type="heading">
					<subject>Case Report</subject>
				</subj-group>
			</article-categories>
			<title-group>
				<article-title>New Application of FFRCT in Clinical Practice: Evaluation of Interarterial Anomalous Coronary Course</article-title>
			</title-group>
			<contrib-group>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0003-4085-8311</contrib-id>
					<name>
						<surname>Trindade</surname>
						<given-names>Fábio Bordin</given-names>
					</name>
					<role>Conception and design of the research,writing of the manuscript,literature review</role>
					<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0001-9652-2927</contrib-id>
					<name>
						<surname>Morais</surname>
						<given-names>Thamara Carvalho</given-names>
					</name>
					<role>critical revision of the manuscript for intellectual content,literature review,realization of the FFRct</role>
					<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
					<xref ref-type="aff" rid="aff2"><sup>2</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0002-3053-3583</contrib-id>
					<name>
						<surname>Dantas</surname>
						<given-names>Roberto Nery</given-names>
						<suffix>Junior</suffix>
					</name>
					<role>critical revision of the manuscript for intellectual content,literature review</role>
					<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
					<xref ref-type="aff" rid="aff2"><sup>2</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0001-5547-6821</contrib-id>
					<name>
						<surname>Torres</surname>
						<given-names>Roberto Vitor Almeida</given-names>
					</name>
					<role>obtaining and reconstructing 2D and 3D images</role>
					<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
					<xref ref-type="aff" rid="aff2"><sup>2</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0002-4932-444X</contrib-id>
					<name>
						<surname>Soares</surname>
						<given-names>Clarice Santos Parreira</given-names>
					</name>
					<role>writing of the manuscript</role>
					<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0001-7215-9369</contrib-id>
					<name>
						<surname>Parga</surname>
						<given-names>José Rodrigues</given-names>
						<suffix>Filho</suffix>
					</name>
					<role>critical revision of the manuscript for intellectual content</role>
					<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
					<xref ref-type="aff" rid="aff2"><sup>2</sup></xref>
				</contrib>
			</contrib-group>
			<aff id="aff1">
				<label>1</label>
				<institution content-type="orgname">Hospital Sírio-Libanês</institution>
				<addr-line>
					<named-content content-type="city">São Paulo</named-content>
					<named-content content-type="state">SP</named-content>
				</addr-line>
				<country country="BR">Brazil</country>
				<institution content-type="original">Hospital Sírio-Libanês, São Paulo, SP – Brazil</institution>
			</aff>
			<aff id="aff2">
				<label>2</label>
				<institution content-type="orgdiv2">Instituto do Coração</institution>
				<institution content-type="orgdiv1">Faculdade de Medicina</institution>
				<institution content-type="orgname">Universidade de São Paulo</institution>
				<addr-line>
					<named-content content-type="city">São Paulo</named-content>
					<named-content content-type="state">SP</named-content>
				</addr-line>
				<country country="BR">Brazil</country>
				<institution content-type="original">Instituto do Coração da Faculdade de Medicina, Universidade de São Paulo (InCor/FMUSP), São Paulo, SP – Brazil</institution>
			</aff>
			<author-notes>
				<corresp id="c01"> Mailing Address: Fábio Bordin Trindade • Hospital Sírio-Libânes. Rua Adma Jafet, 115. CEP: 01308-050. Bela Vista. São Paulo, SP – Brazil E-mail: <email>fabio.trindade@hsl.org.br</email>
				</corresp>
				<fn fn-type="conflict">
					<p>Potential Conflict of Interest</p>
					<p>No potential conflict of interest relevant to this article was reported.</p>
				</fn>
				<fn fn-type="edited-by">
					<p>Editor responsible for the review: Leonardo Sara da Silva</p>
				</fn>
			</author-notes>
			<pub-date date-type="pub" publication-format="electronic">
				<day>10</day>
				<month>05</month>
				<year>2023</year>
			</pub-date>
			<pub-date date-type="collection" publication-format="electronic">
				<year>2023</year>
			</pub-date>
			<volume>36</volume>
			<issue>2</issue>
			<elocation-id>e361</elocation-id>
			<history>
				<date date-type="received">
					<day>8</day>
					<month>11</month>
					<year>2022</year>
				</date>
				<date date-type="rev-recd">
					<day>16</day>
					<month>02</month>
					<year>2023</year>
				</date>
				<date date-type="accepted">
					<day>17</day>
					<month>02</month>
					<year>2023</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>
			<kwd-group xml:lang="en">
				<kwd>Fractional Flow Reserve, Myocardial</kwd>
				<kwd>Congenital Abnormalities</kwd>
				<kwd>Tomography, X-Ray Computed</kwd>
				<kwd>Myocardial Ischemia</kwd>
				<kwd>Machine Learning</kwd>
			</kwd-group>
			<counts>
				<fig-count count="6"/>
				<table-count count="0"/>
				<equation-count count="0"/>
				<ref-count count="8"/>
			</counts>
		</article-meta>
	</front>
	<body>
		<p>A 58-year-old male patient, who worked as an airline pilot, sought emergency cardiology care due to palpitations and ill-defined chest discomfort, which had onset at rest 1 hour before admission, without irradiation or associated symptoms. He had personal history of diabetes mellitus, obesity, generalized anxiety disorder, and a mild COVID-19 episode 3 months prior (not requiring hospitalization), in addition to family history of early coronary artery disease (his father had an infarction at 40 years of age). Physical examination showed no relevant alterations. The electrocardiogram showed only sinus tachycardia and nonspecific ventricular repolarization changes. Serial troponin testing was performed, and all results were within normal limits. Echocardiogram showed preserved left ventricular ejection fraction (71%), absence of alterations in segmental contractility, and discreet diastolic dysfunction (altered relaxation). Following the institutional chest pain protocol, the patient was referred for computed tomography angiography (CTA) of the coronary arteries, which showed right coronary artery with an anomalous origin in the left coronary sinus and an interarterial (suprapulmonary) course, with significant luminal reduction (&gt; 50%) in the ostium and proximal segment (<xref ref-type="fig" rid="f01">Figure 1</xref>). After the diagnostic finding, the patient was recruited in a research protocol for evaluation of myocardial ischemia by tomography by means of non-invasive quantification of the myocardial fractional flow reserve (FFRCT). Software based on artificial intelligence (cFFR, version 3.0.0) available on a research platform (Syngovia Frontier Platform, Siemens Healthineers) was used. The calculation of FFRCT demonstrated ischemia in the right coronary artery territory (<xref ref-type="fig" rid="f02">Figure 2</xref>; FFRCT 0.63 [reference values: FFRCT ≤ 0.75 = indicates ischemia; between 0.76 and 0.80 = borderline zone; &gt; 0.80 = excludes ischemia]).<sup><xref ref-type="bibr" rid="B1">1</xref></sup> The patient continued investigation with coronary angiography with invasive FFR (iFFR), which confirmed flow limitation in the anomalous right coronary artery (<xref ref-type="fig" rid="f03">Figure 3A</xref>; iFFR 0.68 [reference values: iFFR ≤ 0.8 indicates ischemia; &gt; 0.8 excludes ischemia]).<sup><xref ref-type="bibr" rid="B2">2</xref></sup> At that moment, treatment with drug-eluting stent implantation was chosen (<xref ref-type="fig" rid="f03">Figure 3B</xref>), with good angiographic results and no complications. After 6 months, the patient was asymptomatic, with no recurrence of symptoms.</p>
		<p>
			<fig id="f01">
				<label>Figure 1</label>
				<caption>
					<title>– Three-dimensional reconstruction of the coronary tree with origin of the anomalous right coronary artery (arrow) in the left coronary sinus and interarterial course (A); two-dimensional curved planar reconstruction of the anomalous right coronary artery (arrow) with significant luminal reduction (&gt; 50%) of the ostium and proximal segment (B).</title>
				</caption>
				<graphic xlink:href="2675-312X-dic-36-02-e361-gf01.tif"/>
			</fig>
		</p>
		<p>
			<fig id="f02">
				<label>Figure 2</label>
				<caption>
					<title>– Two-dimensional curved planar reformatting (A), with delimitation of the coronary lumen (B) of the anomalous right coronary artery. Three-dimensional reconstruction with representation of FFRCT values throughout the entire coronary tree (C). FFRCT demonstrates coronary flow limitation, calculated approximately 1 cm after the luminal reduction in the ostium/proximal third of the anomalous right coronary artery (arrow).</title>
				</caption>
				<graphic xlink:href="2675-312X-dic-36-02-e361-gf02.tif"/>
			</fig>
		</p>
		<p>
			<fig id="f03">
				<label>Figure 3</label>
				<caption>
					<title>– Ischemia in the right coronary artery confirmed by iFFR (reference value for ischemia ≤ 0.8) (A); invasive coronary angiography demonstrating the final result after drug-eluting stent implantation (arrow) in the proximal segment of the anomalous pathway (B).</title>
				</caption>
				<graphic xlink:href="2675-312X-dic-36-02-e361-gf03.tif"/>
			</fig>
		</p>
		<sec sec-type="discussion">
			<title>Discussion</title>
			<p>Anomalous origin and course of coronary arteries are rare congenital heart diseases, affecting less than 1% of the general population.<sup><xref ref-type="bibr" rid="B3">3</xref>,<xref ref-type="bibr" rid="B4">4</xref></sup> Anomalous coronary origin with an interarterial (suprapulmonary) course is characterized by the course of the coronary artery between the ascending aorta and the pulmonary artery trunk, most commonly involving the right coronary artery.<sup><xref ref-type="bibr" rid="B3">3</xref>,<xref ref-type="bibr" rid="B5">5</xref></sup> Most individuals are asymptomatic, but, among symptomatic patients, chest pain and dyspnea on exertion are the most prevalent complaints. There is also an increase in rates of arrhythmia, sudden death, and acute myocardial infarction.<sup><xref ref-type="bibr" rid="B4">4</xref>,<xref ref-type="bibr" rid="B6">6</xref></sup> Sudden death is the main complication of this anatomical variant, occurring in approximately 30% of patients.<sup><xref ref-type="bibr" rid="B3">3</xref>,<xref ref-type="bibr" rid="B4">4</xref>,<xref ref-type="bibr" rid="B6">6</xref></sup> In these cases, the narrowing and stretching of the anomalous ostium, mainly during physical exercise and in stressful situations, with consequent reduction in coronary flow, is the substrate for potentially fatal ischemic alterations.<sup><xref ref-type="bibr" rid="B3">3</xref>,<xref ref-type="bibr" rid="B4">4</xref>,<xref ref-type="bibr" rid="B6">6</xref></sup> Since electrocardiogram, in most cases, does not reveal ischemic alterations, diagnosis is generally made through an incidental finding on imaging exams.<sup><xref ref-type="bibr" rid="B4">4</xref></sup> These exams are of great importance, especially coronary CTA, which, in addition to being a non-invasive exam with high negative predictive value, allows detailed anatomical visualization (angle of the origin, presence of intramural trajectory in the aorta, degree of ostial/proximal luminal reduction) and the correct classification in relation to the pulmonary valve plane (suprapulmonary versus subpulmonary).<sup><xref ref-type="bibr" rid="B2">2</xref>,<xref ref-type="bibr" rid="B6">6</xref>,<xref ref-type="bibr" rid="B7">7</xref></sup></p>
			<p>Recent studies have demonstrated that coronary CTA is an accurate test for identifying myocardial ischemia through FFRCT, when compared to invasive measurement (iFFR) by coronary angiography.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B2">2</xref>,<xref ref-type="bibr" rid="B7">7</xref>,<xref ref-type="bibr" rid="B8">8</xref></sup> The detection of ischemia in coronary CTA is of great importance in decision-making, mainly in plaques considered moderate (50% to 69% luminal reduction) or when there is diagnostic doubt, reducing the number of unnecessary referrals to coronary angiography in cases without ischemia on FFRct.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B2">2</xref>,<xref ref-type="bibr" rid="B8">8</xref></sup> Due to the excellent accuracy between the methods in the analysis of a coronary tree without anomaly, the applicability of the method in the context of coronary anomaly has been extrapolated.<sup><xref ref-type="bibr" rid="B5">5</xref>,<xref ref-type="bibr" rid="B7">7</xref></sup> Our group applied the most current version of a tool for calculating FFRCT currently available only on a research platform developed by Siemens Healthineers (cFRR, version 3.0.0) in the clinical case described. This research tool is available for installation on standard configuration computers, and it uses artificial intelligence tools, with reduced processing time.<sup><xref ref-type="bibr" rid="B8">8</xref></sup> Currently, commercially available options require the step of sending images in DICOM format for processing in specific centers, with delivery of results at least 24 hours after the images have been sent.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B2">2</xref></sup> The research tool used in this clinical case has advantages, such as fast processing time on standard configuration computers in the analysis room and use of tomographic images from the standard routine protocol, without requiring the addition of a specific protocol or a higher dose of radiation, without the use of stressors.<sup><xref ref-type="bibr" rid="B2">2</xref>,<xref ref-type="bibr" rid="B8">8</xref></sup> This tool, in general, has some limitations, such as difficulty in defining the coronary borders in the presence of excessive calcification, and the need for high-quality images, without movement artifacts, for adequate automatic detection of the central luminal line and the lines that delimit the coronary borders, allowing adequate calculation of FFRct.<sup><xref ref-type="bibr" rid="B8">8</xref></sup> It is important to emphasize that this tool distinguishes the interarterial pathways associated with ischemia, considering only the flow obstacle during rest, without estimating the risk of ischemic events associated with dynamic changes secondary to intense exercise. Use of this tool is scarce in the literature,<sup><xref ref-type="bibr" rid="B5">5</xref></sup> and it still does not have a robust body of evidence. Nevertheless, in the clinical case described, the FFRCT tool was applied in a context different than what is usual, where luminal reduction was not determined by coronary atheromatosis, but by ostial angulation and compression of the proximal segment of the anomalous interarterial pathway. The ischemic response was considered a parameter of poor prognosis; subsequently, the confirmatory invasive functional test (iFFR) was indicated to assist in the therapeutic decision.</p>
			<p>Treatment of coronary anomalies involves the following two strategies: conservative treatment with clinical follow-up of patients in asymptomatic cases; or invasive (surgical or percutaneous) treatment, myocardial revascularization surgery being the preferred technique in symptomatic patients under 30 years of age.<sup><xref ref-type="bibr" rid="B4">4</xref>,<xref ref-type="bibr" rid="B6">6</xref>,<xref ref-type="bibr" rid="B7">7</xref></sup> Percutaneous coronary intervention with drug-eluting stent implantation, as in the clinical case described, has emerged more recently as a promising alternative therapy.<sup><xref ref-type="bibr" rid="B4">4</xref></sup></p>
		</sec>
		<sec sec-type="conclusions">
			<title>Conclusion</title>
			<p>Considered a rare anatomical variation, interarterial course is a potentially fatal coronary anomaly, even in asymptomatic patients. In the case described, the novel application of FFRCT based on artificial intelligence proved to be an excellent diagnostic alternative in this anatomical context, given that it is a non-invasive method capable of detecting ischemic coronary luminal reductions in accordance with iFFR, with future potential to guide planning and decision-making in myocardial revascularization interventions.</p>
		</sec>
	</body>
	<back>
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							<given-names>JM</given-names>
						</name>
						<etal>et al</etal>
					</person-group>
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			</ref>
		</ref-list>
		<fn-group>
			<fn fn-type="other">
				<label/>
				<p>Study Association</p>
				<p>This study is not associated with any thesis or dissertation work.</p>
			</fn>
			<fn fn-type="other">
				<label/>
				<p>Ethics Approval and Consent to Participate</p>
				<p>This article does not contain any studies with human participants or animals performed by any of the authors.</p>
			</fn>
		</fn-group>
		<fn-group>
			<fn fn-type="supported-by">
				<p>Sources of Funding: There were no external funding sources for this study.</p>
			</fn>
		</fn-group>
	</back>
	<sub-article article-type="translation" id="TRpt" xml:lang="pt">
		<front-stub>
			<article-id pub-id-type="doi">10.36660/abcimg.2023361</article-id>
			<article-categories>
				<subj-group subj-group-type="heading">
					<subject>Relato de Caso</subject>
				</subj-group>
			</article-categories>
			<title-group>
				<article-title>Nova Aplicação do FFRct na Prática Clínica: Avaliação de Trajeto Coronariano Anômalo Interarterial</article-title>
			</title-group>
			<contrib-group>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0003-4085-8311</contrib-id>
					<name>
						<surname>Trindade</surname>
						<given-names>Fábio Bordin</given-names>
					</name>
					<role>Concepção e desenho da pesquisa,redação do manuscrito,revisão da literatura</role>
					<xref ref-type="aff" rid="aff1002"><sup>1</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0001-9652-2927</contrib-id>
					<name>
						<surname>Morais</surname>
						<given-names>Thamara Carvalho</given-names>
					</name>
					<role>revisão crítica do manuscrito quanto ao conteúdo intelectual importante,revisão da literatura,realização do FFRct</role>
					<xref ref-type="aff" rid="aff1002"><sup>1</sup></xref>
					<xref ref-type="aff" rid="aff2002"><sup>2</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0002-3053-3583</contrib-id>
					<name>
						<surname>Dantas</surname>
						<given-names>Roberto Nery</given-names>
						<suffix>Junior</suffix>
					</name>
					<role>revisão crítica do manuscrito quanto ao conteúdo intelectual importante,revisão da literatura</role>
					<xref ref-type="aff" rid="aff1002"><sup>1</sup></xref>
					<xref ref-type="aff" rid="aff2002"><sup>2</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0001-5547-6821</contrib-id>
					<name>
						<surname>Torres</surname>
						<given-names>Roberto Vitor Almeida</given-names>
					</name>
					<role>obtenção e reconstrução das imagens em 2D e 3D</role>
					<xref ref-type="aff" rid="aff1002"><sup>1</sup></xref>
					<xref ref-type="aff" rid="aff2002"><sup>2</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0002-4932-444X</contrib-id>
					<name>
						<surname>Soares</surname>
						<given-names>Clarice Santos Parreira</given-names>
					</name>
					<role>redação do manuscrito</role>
					<xref ref-type="aff" rid="aff1002"><sup>1</sup></xref>
				</contrib>
				<contrib contrib-type="author">
					<contrib-id contrib-id-type="orcid">0000-0001-7215-9369</contrib-id>
					<name>
						<surname>Parga</surname>
						<given-names>José Rodrigues</given-names>
						<suffix>Filho</suffix>
					</name>
					<role>revisão crítica do manuscrito quanto ao conteúdo intelectual importante</role>
					<xref ref-type="aff" rid="aff1002"><sup>1</sup></xref>
					<xref ref-type="aff" rid="aff2002"><sup>2</sup></xref>
				</contrib>
			</contrib-group>
			<aff id="aff1002">
				<label>1</label>
				<country country="BR">Brasil</country>
				<institution content-type="original">Hospital Sírio-Libanês, São Paulo, SP – Brasil</institution>
			</aff>
			<aff id="aff2002">
				<label>2</label>
				<country country="BR">Brasil</country>
				<institution content-type="original">Instituto do Coração da Faculdade de Medicina, Universidade de São Paulo (InCor/FMUSP), São Paulo, SP – Brasil</institution>
			</aff>
			<author-notes>
				<corresp id="c01002"> Correspondência: Fábio Bordin Trindade • Hospital Sírio-Libânes. Rua Adma Jafet, 115. CEP: 01308-050. Bela Vista. São Paulo, SP – Brasil E-mail: fabio.trindade@hsl.org.br </corresp>
				<fn fn-type="conflict">
					<p>Potencial Conflito de Interesse</p>
					<p>Declaro não haver conflito de interesses pertinentes.</p>
				</fn>
				<fn fn-type="edited-by">
					<p>Editor responsável pela revisão: Leonardo Sara da Silva</p>
				</fn>
			</author-notes>
			<kwd-group xml:lang="pt">
				<kwd>Reserva fracionada de fluxo miocárdico</kwd>
				<kwd>Anormalidades Congênitas</kwd>
				<kwd>Tomografia computadorizada por raios X</kwd>
				<kwd>Isquemia Miocárdica</kwd>
				<kwd>Aprendizado de máquina</kwd>
			</kwd-group>
		</front-stub>
		<body>
			<p>Paciente masculino de 58 anos, piloto de avião, procurou pronto-atendimento cardiológico devido a palpitações e desconforto torácico mal caracterizado, com início em repouso há uma hora da admissão, sem irradiação ou sintomas associados. Apresentava antecedentes pessoais de diabetes mellitus, obesidade, transtorno de ansiedade generalizada, episódio leve de COVID-19 há 3 meses (sem necessidade de internação) e história familiar de doença arterial coronariana precoce (pai com infarto aos 40 anos). Exame físico sem alterações relevantes. O eletrocardiograma apresentava apenas taquicardia sinusal e alterações de repolarização ventricular inespecíficas. Foi realizada coleta seriada de troponina, todas dentro da normalidade. O ecocardiograma demonstrou fração de ejeção do ventrículo esquerdo preservada (71%), ausência de alterações da contratilidade segmentar e discreta disfunção diastólica (alteração de relaxamento). Seguindo o protocolo de dor torácica institucional, o paciente foi encaminhado para angiotomografia (angioTC) de artérias coronárias que evidenciou artéria coronária direita (CD) com origem anômala no seio coronariano esquerdo e trajeto interarterial (suprapulmonar), com redução luminal significativa (&gt;50%) no óstio e segmento proximal (<xref ref-type="fig" rid="f01002">Figura 1</xref>). Após achado diagnóstico, o paciente foi recrutado em protocolo de pesquisa, para avaliação de isquemia miocárdica por tomografia através da quantificação não-invasiva da reserva fracionada de fluxo miocárdico (FFRct). Foi utilizado software baseado em inteligência artificial (cFFR, versão 3.0.0) disponível em plataforma de pesquisa (Syngovia Frontier Platform, Siemens Healthineers). O cálculo da FFRct demonstrou isquemia em território de CD (<xref ref-type="fig" rid="f02002">Figura 2</xref>; FFRct 0,63 – Valores de referência: FFRct ≤ 0,75 = indica isquemia; entre 0,76 e 0,80 = zona <italic>borderline</italic>; &gt; 0,80 = exclui isquemia).<sup><xref ref-type="bibr" rid="B1">1</xref></sup> O paciente prosseguiu investigação com cineangiocoronariografia com FFR invasivo (FFRi) que confirmou a limitação de fluxo na CD anômala (<xref ref-type="fig" rid="f03002">Figura 3A</xref>; FFRi 0,68 – Valores de referência: FFRi ≤ 0,8 indica isquemia; &gt; 0,8 exclui isquemia),<sup><xref ref-type="bibr" rid="B2">2</xref></sup> sendo optado naquele momento por tratamento com implante de <italic>stent</italic> farmacológico (<xref ref-type="fig" rid="f03002">Figura 3B</xref>), com bom resultado angiográfico e sem intercorrências. Após 6 meses, o paciente encontrava-se assintomático e sem recorrência dos sintomas.</p>
			<p>
				<fig id="f01002">
					<label>Figura 1</label>
					<caption>
						<title>– Reconstrução 3D da árvore coronariana com origem da CD anômala (seta) no seio coronariano esquerdo e trajeto interarterial (A); Reconstrução planar curva em 2D da CD anômala (seta) com redução luminal significativa (&gt; 50%) do óstio e do segmento proximal (B).</title>
					</caption>
					<graphic xlink:href="2675-312X-dic-36-02-e361-gf01-pt.tif"/>
				</fig>
			</p>
			<p>
				<fig id="f02002">
					<label>Figura 2</label>
					<caption>
						<title>– Reformatação planar curva em 2D (A), com a delimitação do lúmen coronariano (B) da CD anômala. Reconstrução 3D com representação dos valores de FFRct por toda árvore coronariana (C). FFRct demonstra limitação de fluxo coronariano, calculado cerca de 1 cm após a redução luminal no óstio/terço proximal da CD anômala (seta).</title>
					</caption>
					<graphic xlink:href="2675-312X-dic-36-02-e361-gf02-pt.tif"/>
				</fig>
			</p>
			<p>
				<fig id="f03002">
					<label>Figura 3</label>
					<caption>
						<title>– FFRi confirmando isquemia em CD (valor de referência para isquemia ≤ 0,8) (A); Cineangiocoronariografia invasiva demonstrado resultado final após implante de stent farmacológico (seta) no segmento proximal do trajeto anômalo (B).</title>
					</caption>
					<graphic xlink:href="2675-312X-dic-36-02-e361-gf03-pt.tif"/>
				</fig>
			</p>
			<sec sec-type="discussion">
				<title>Discussão</title>
				<p>Anomalias coronarianas de origem e trajeto são cardiopatias congênitas raras, acometendo menos de 1% da população geral.<sup><xref ref-type="bibr" rid="B3">3</xref>,<xref ref-type="bibr" rid="B4">4</xref></sup> A origem anômala coronariana com trajeto interarterial (suprapulmonar) é caracterizada pelo trajeto da artéria coronária entre a aorta ascendente e o tronco da artéria pulmonar, envolvendo mais comumente a CD.<sup><xref ref-type="bibr" rid="B3">3</xref>,<xref ref-type="bibr" rid="B5">5</xref></sup> A maioria dos indivíduos é assintomática, porém dentre os sintomáticos, dor torácica e dispneia aos esforços são as queixas mais prevalentes. Há também aumento das taxas de arritmias, morte súbita e infarto agudo do miocárdio.<sup><xref ref-type="bibr" rid="B4">4</xref>,<xref ref-type="bibr" rid="B6">6</xref></sup> Morte súbita é a principal complicação dessa variante anatômica e ocorre em aproximadamente 30% dos pacientes.<sup><xref ref-type="bibr" rid="B3">3</xref>,<xref ref-type="bibr" rid="B4">4</xref>,<xref ref-type="bibr" rid="B6">6</xref></sup> Nesses casos o estreitamento e estiramento do óstio anômalo, principalmente ao exercício físico e em situações estressantes, com consequente redução do fluxo coronariano, é o substrato para alterações isquêmicas potencialmente fatais.<sup><xref ref-type="bibr" rid="B3">3</xref>,<xref ref-type="bibr" rid="B4">4</xref>,<xref ref-type="bibr" rid="B6">6</xref></sup> Como o eletrocardiograma na maioria das vezes não revela alterações isquêmicas, o diagnóstico geralmente é feito através de um achado incidental em exames de imagem.<sup><xref ref-type="bibr" rid="B4">4</xref></sup> Esses exames são de grande importância, em especial a angioTC de coronárias que, além de ser um exame não invasivo, com elevado valor preditivo negativo, permite uma detalhada visualização anatômica (angulação da sua origem, presença de trajeto intramural na aorta, grau de redução luminal ostial/proximal) e a correta classificação em relação ao plano valvar pulmonar (suprapulmonar x subpulmonar).<sup><xref ref-type="bibr" rid="B2">2</xref>,<xref ref-type="bibr" rid="B6">6</xref>,<xref ref-type="bibr" rid="B7">7</xref></sup></p>
				<p>Estudos recentes demonstraram que a angioTC de coronárias é um exame acurado para identificação de isquemia miocárdica através da FFRct quando comparado à medida invasiva (FFRi) pela cineangiocoronariografia.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B2">2</xref>,<xref ref-type="bibr" rid="B7">7</xref>,<xref ref-type="bibr" rid="B8">8</xref></sup> A detecção de isquemia na angioTC de coronárias tem grande importância na tomada de decisão principalmente em placas consideradas moderadas (redução luminal 50% a 69%) ou quando há dúvida diagnóstica, reduzindo o número de encaminhamentos desnecessários à cineangiocoronariografia nos casos sem isquemia na FFRct.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B2">2</xref>,<xref ref-type="bibr" rid="B8">8</xref></sup> Devido à excelente acurácia entre os métodos na análise da árvore coronariana sem anomalia, extrapolou-se a aplicabilidade do método no contexto da anomalia coronariana.<sup><xref ref-type="bibr" rid="B5">5</xref>,<xref ref-type="bibr" rid="B7">7</xref></sup> Nosso grupo aplicou uma ferramenta para cálculo da FFRct atualmente disponível apenas em plataforma de pesquisa desenvolvida pela Siemens Healthineers na sua versão mais atual (cFRR, versão 3.0.0) no caso clínico descrito. Essa ferramenta de pesquisa está disponível para instalação em computadores de configuração-padrão e utiliza ferramentas de inteligência artificial, com reduzido tempo de processamento.<sup><xref ref-type="bibr" rid="B8">8</xref></sup> Atualmente as opções comercialmente disponíveis exigem a etapa de envio da imagens em formato DICOM para processamento em centros específicos e entrega do resultado pelo menos 24 horas após o envio das imagens.<sup><xref ref-type="bibr" rid="B1">1</xref>,<xref ref-type="bibr" rid="B2">2</xref></sup> A ferramenta de pesquisa utilizada no caso clínico possui vantagens, como o rápido processamento através de computadores de configuração-padrão das salas de laudos; utilização de imagens tomográficas do protocolo padrão da rotina, sem adição de protocolo específico, ou maior dose de radiação e sem a utilização de agentes estressores.<sup><xref ref-type="bibr" rid="B2">2</xref>,<xref ref-type="bibr" rid="B8">8</xref></sup> A ferramenta, no geral, possui algumas limitações, como a dificuldade de definição dos bordos coronarianos na presença de calcificação excessiva, e a necessidade de imagens de alta qualidade, sem artefatos de movimento, para uma adequada detecção automática da linha luminal central e das linhas que delimitam os bordos coronarianos, permitindo o cálculo adequado da FFRct.<sup><xref ref-type="bibr" rid="B8">8</xref></sup> É importante ressaltar que a utilização dessa ferramenta discrimina os trajetos interarteriais associados à isquemia considerando apenas o obstáculo ao fluxo durante o repouso, não estimando o risco de eventos isquêmicos associados às alterações dinâmicas secundárias ao exercício intenso. Sua utilização também é escassa na literatura,<sup><xref ref-type="bibr" rid="B5">5</xref></sup> ainda sem um robusto corpo de evidências. No entanto, no caso clínico descrito, a ferramenta de FFRct foi aplicada num contexto diferente do habitual em que a redução luminal não foi determinada por ateromatose coronariana e sim pela angulação ostial e compressão do segmento proximal do trajeto anômalo interarterial. A resposta isquêmica foi considerada um parâmetro de mau prognóstico, e posteriormente foi indicado o exame funcional invasivo confirmatório (FFRi) para auxiliar na decisão terapêutica.</p>
				<p>O tratamento da anomalia coronariana envolve duas estratégias: tratamento conservador com seguimento clínico dos pacientes em casos assintomáticos; ou invasivo (cirúrgico ou percutâneo), sendo a cirurgia de revascularização miocárdica a técnica de preferência em sintomáticos abaixo de 30 anos.<sup><xref ref-type="bibr" rid="B4">4</xref>,<xref ref-type="bibr" rid="B6">6</xref>,<xref ref-type="bibr" rid="B7">7</xref></sup> A intervenção coronariana percutânea com implante de <italic>stent</italic> farmacológico, como no caso clínico descrito, desponta mais recentemente como uma alternativa terapêutica promissora.<sup><xref ref-type="bibr" rid="B4">4</xref></sup></p>
			</sec>
			<sec sec-type="conclusions">
				<title>Conclusão</title>
				<p>Considerado uma variação anatômica rara, o trajeto interarterial é uma anomalia coronariana potencialmente fatal, inclusive em pacientes assintomáticos. No caso descrito, a nova aplicação de FFRct baseada em inteligência artificial demonstrou ser uma excelente alternativa diagnóstica nesse contexto anatômico, por ser um método não invasivo capaz de detectar reduções luminais coronarianas isquêmicas em concordância com o FFR invasivo, com potencial futuro de orientar o planejamento e decisão de intervenções de revascularização miocárdica.</p>
			</sec>
		</body>
		<back>
			<fn-group>
				<fn fn-type="other">
					<label/>
					<p>Vinculação Acadêmica</p>
					<p>Não há vinculação deste estudo a programas de pós-graduação.</p>
				</fn>
				<fn fn-type="other">
					<label/>
					<p>Aprovação Ética e Consentimento Informado</p>
					<p>Este artigo não contém estudos com humanos ou animais realizados por nenhum dos autores.</p>
				</fn>
			</fn-group>
			<fn-group>
				<fn fn-type="supported-by">
					<p>Fontes de Financiamento: O presente estudo não teve fontes de financiamento externas.</p>
				</fn>
			</fn-group>
		</back>
	</sub-article>
</article>