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  <front>
    <journal-meta>
      <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-loc>S&#227;o Paulo, SP, Brazil</publisher-loc>
      </publisher>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="publisher-id" specific-use="scielo-v3">TSQrLbfN7hjrxsHkC9pJDHF</article-id>
      <article-id pub-id-type="other">00017</article-id>
      <article-id pub-id-type="publisher-id" specific-use="scielo-v2">S0066-782X2011001300017</article-id>
      <article-id pub-id-type="publisher-id" specific-use="scielo-v1">S0066-782X(11)09700417</article-id>
      <article-id pub-id-type="doi">10.1590/S0066-782X2011001300017</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Relato de Caso</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>F&#237;stula coronariana para ventr&#237;culo esquerdo: diagn&#243;stico por tomografia computadorizada</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Mendon&#231;a</surname>
            <given-names>Roberto Moreno</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Bandeira</surname>
            <given-names>Rodrigo Lima</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Fonseca</surname>
            <given-names>Fredson J. S</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Macedo Filho</surname>
            <given-names>Robson</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
      </contrib-group>
      <aff id="aff01">
        <addr-line>
          <named-content content-type="city">Natal</named-content>
          <named-content content-type="state">RN</named-content>
        </addr-line>
        <institution content-type="orgname">Instituto de Radiologia de Natal</institution>
        <country country="BR">Brasil</country>
      </aff>
      <pub-date date-type="collection" publication-format="electronic">
        <month>10</month>
        <year>2011</year>
      </pub-date>
      <volume>97</volume>
      <issue>4</issue>
      <fpage>e82</fpage>
      <lpage>e85</lpage>
      <history>
        <date date-type="rev-recd">
          <day>03</day>
          <month>08</month>
          <year>2010</year>
        </date>
        <date date-type="received">
          <day>01</day>
          <month>05</month>
          <year>2010</year>
        </date>
        <date date-type="accepted">
          <day>16</day>
          <month>09</month>
          <year>2010</year>
        </date>
      </history>
      <permissions>
        <license license-type="open-access" xlink:href="http://creativecommons.org/licenses/by-nc/4.0/" xml:lang="en">
          <license-p>This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.</license-p>
        </license>
      </permissions>
      <abstract>
        <p>F&#237;stulas de art&#233;rias coron&#225;rias s&#227;o raras, sendo diagnosticadas mais frequentemente pelo ecocardiograma ou pela cineangiocoronariografia, entretanto, a angiotomografia computadorizada (angio-TC) das coron&#225;rias ganha espa&#231;o. Essa patologia apresenta incid&#234;ncia baix&#237;ssima, sendo as f&#237;stulas originadas da coron&#225;ria direita mais frequentes. F&#237;stulas coronarianas para c&#226;maras card&#237;acas direitas s&#227;o mais incidentes, sendo raras para o ventr&#237;culo esquerdo (VE). O tratamento pode ser cir&#250;rgico ou percut&#226;neo. Este relato descreve caso de f&#237;stula coronariana para VE diagnosticada pela angio-TC das coron&#225;rias em homem de 46 anos, hipertenso, assintom&#225;tico com teste ergom&#233;trico positivo para isquemia. Angio-TC de coron&#225;rias descartou doen&#231;a obstrutiva, por&#233;m revelou f&#237;stula coronariana conectando-se com cavidade ventricular esquerda.</p>
      </abstract>
      <kwd-group xml:lang="pt" kwd-group-type="author-generated">
        <kwd>Doen&#231;as cardiovasculares</kwd>
        <kwd>fistula arterio-arterial</kwd>
        <kwd>ventr&#237;culos do cora&#231;&#227;o</kwd>
        <kwd>diagn&#243;stico</kwd>
        <kwd>tomografia computadorizada</kwd>
      </kwd-group>
      <pub-date publication-format="electronic" date-type="pub">
        <day>30</day>
        <month>11</month>
        <year>2011</year>
      </pub-date>
    </article-meta>
  </front>
  <body>
    <p>
      <bold>RELATO DE CASO</bold>
    </p>
    <p>
      <bold>F&#237;stula coronariana para ventr&#237;culo esquerdo: diagn&#243;stico por tomografia computadorizada</bold>
    </p>
    <p>
      <bold>Roberto Moreno Mendon&#231;a; Rodrigo Lima Bandeira; Fredson J. S. Fonseca; Robson Macedo Filho</bold>
    </p>
    <p>Instituto de Radiologia de Natal - IRN; Natal; RN - Brasil</p>
    <p>
      <xref ref-type="corresp" rid="endb">Correspond&#234;ncia</xref>
    </p>
    <p>
      <bold>RESUMO</bold>
    </p>
    <p>F&#237;stulas de art&#233;rias coron&#225;rias s&#227;o raras, sendo diagnosticadas mais frequentemente pelo ecocardiograma ou pela cineangiocoronariografia, entretanto, a angiotomografia computadorizada (angio-TC) das coron&#225;rias ganha espa&#231;o. Essa patologia apresenta incid&#234;ncia baix&#237;ssima, sendo as f&#237;stulas originadas da coron&#225;ria direita mais frequentes. F&#237;stulas coronarianas para c&#226;maras card&#237;acas direitas s&#227;o mais incidentes, sendo raras para o ventr&#237;culo esquerdo (VE). O tratamento pode ser cir&#250;rgico ou percut&#226;neo. </p>
    <p> Este relato descreve caso de f&#237;stula coronariana para VE diagnosticada pela angio-TC das coron&#225;rias em homem de 46 anos, hipertenso, assintom&#225;tico com teste ergom&#233;trico positivo para isquemia. Angio-TC de coron&#225;rias descartou doen&#231;a obstrutiva, por&#233;m revelou f&#237;stula coronariana conectando-se com cavidade ventricular esquerda.</p>
    <p><bold>Palavras-chave:</bold> Doen&#231;as cardiovasculares, fistula arterio-arterial, ventr&#237;culos do cora&#231;&#227;o, diagn&#243;stico, tomografia computadorizada.</p>
    <p>
      <bold>Introdu&#231;&#227;o</bold>
    </p>
    <p>As f&#237;stulas coronarianas (FC) s&#227;o conex&#245;es diretas de uma ou mais art&#233;rias coron&#225;rias para c&#226;maras card&#237;acas ou grande vaso<sup>1</sup>. As anomalias cong&#234;nitas s&#227;o mais comuns que as adquiridas<sup>2</sup>, sendo encontradas em at&#233; 0,2% das cineangiocoronariografias de rotina<sup>3</sup>.</p>
    <p>A maioria dos pacientes &#233; assintom&#225;tica<sup>3</sup>, mas, quando apresenta sintomas, estes podem ser: fadiga, dispneia de esfor&#231;o, palpita&#231;&#245;es e dor tor&#225;cica isqu&#234;mica. Sopros cont&#237;nuos podem ser auscultados, sendo semelhantes ao de um canal arterial patente<sup>4</sup>.</p>
    <p>Como proped&#234;utica complementar, a eletrocardiografia pode ser normal. Geralmente, o diagn&#243;stico &#233; realizado pelo ecocardiograma, especialmente quando h&#225; dilata&#231;&#227;o da art&#233;ria coron&#225;ria envolvida ou fluxo coronariano de alto d&#233;bito<sup>5</sup>, sendo a cineangiocoronariografia o padr&#227;o ouro para o diagn&#243;stico, revelando detalhes anat&#244;micos importantes para o tratamento<sup>2</sup>. </p>
    <p>Este relato descreve um caso raro de f&#237;stula coronariana para o VE diagnosticada pela angio-TC das art&#233;rias coron&#225;rias.</p>
    <p>
      <bold>Relato do caso</bold>
    </p>
    <p>Trata-se de paciente masculino, com 46 anos, obeso, hipertenso e dislipid&#234;mico. Ao exame f&#237;sico, o mesmo apresentava ritmo card&#237;aco regular em tr&#234;s tempos, PA: 160 x 100 mmHg. Encontrava-se assintom&#225;tico em investiga&#231;&#227;o ambulatorial para doen&#231;a arterial coronariana (DAC). </p>
    <p>A prova isqu&#234;mica obtida por meio de teste ergom&#233;trico foi positiva. Ent&#227;o, com a finalidade de excluir DAC, realizou-se uma angio-TC das art&#233;rias coron&#225;rias, que revelou art&#233;rias coron&#225;rias acentuadamente dilatadas e tortuosas, al&#233;m de grande f&#237;stula conectando a art&#233;ria descendente anterior com a coron&#225;ria direita e desembocadura &#250;nica para a cavidade do VE, adjacente ao folheto posterior da valva mitral (Figuras).</p>
    <p>
      <bold>M&#233;todos</bold>
    </p>
    <p>Revisaram-se o exame e a hist&#243;ria cl&#237;nica do paciente no arquivo digital de imagens (PACS). Obteve-se a autoriza&#231;&#227;o do paciente para a utiliza&#231;&#227;o das imagens para relato de caso. </p>
    <p>O equipamento utilizado foi o da <italic>Philips Medical Systems</italic> modelo <italic>Brilliance 16-MDCT</italic>.</p>
    <p>Com o paciente em dec&#250;bito dorsal, em pausa respirat&#243;ria (apneia de 15 segundos), sob sincroniza&#231;&#227;o eletrocardiogr&#225;fica (ECG), cortes tomogr&#225;ficos do cora&#231;&#227;o com 0,75 mm de espessura foram obtidos, utilizando 80 ml de contraste iodado n&#227;o i&#244;nico (Optiray 350 mg/ml) em bomba de infus&#227;o a 5 ml/segundo, seguido de 40 ml de soro fisiol&#243;gico 0,9% com a mesma velocidade de infus&#227;o. As imagens foram visibilizadas em esta&#231;&#227;o de trabalho da <italic>Philips Medical Systems </italic>modelo <italic>Brilliance CT</italic>. Foram realizadas reformata&#231;&#245;es multiplanares (MPR), multiplanares curvo (MPRc) e reconstru&#231;&#245;es em 3D com t&#233;cnica de <italic>volumerendering</italic> (VR) (<xref ref-type="fig" rid="a17fig01m">Figuras 1</xref> e <xref ref-type="fig" rid="a17fig02m">2</xref>).</p>
    <p content-type="asset">
      <fig id="a17fig01m">
        <graphic xlink:href="1678-4170-abc-97-04-0e82-00017-gf01.jpg"/></fig>
    </p>
    <p content-type="asset">
      <fig id="a17fig02m">
        <graphic xlink:href="1678-4170-abc-97-04-0e82-00017-gf02.jpg"/></fig>
    </p>
    <p>
      <bold>Discuss&#227;o</bold>
    </p>
    <p>A incid&#234;ncia de f&#237;stula coronariana entre as cardiopatias cong&#234;nitas &#233; baixa, totalizando apenas 0,2% a 0,4%. Foi descrita pela primeira vez em 1886 e a primeira corre&#231;&#227;o cir&#250;rgica com &#234;xito foi realizada em 1947<sup>1</sup>. A origem cong&#234;nita &#233; ainda mais observada do que a adquirida<sup>2</sup> e anomalias associadas podem ocorrer, sendo descritas na literatura associa&#231;&#245;es com persist&#234;ncia de canal arterial, tetralogia de Fallot, comunica&#231;&#227;o interventricular e ainda cardiopatias adquiridas<sup>5</sup>. As adquiridas podem ser infecciosas, traum&#225;ticas ou iatrog&#234;nicas<sup>2</sup>. H&#225; relatos tamb&#233;m de f&#237;stulas coronarianas associadas a eletrodos permanentes de marca-passo por eros&#227;o, ap&#243;s cirurgia card&#237;aca, angioplastia coronariana ou infarto agudo do mioc&#225;rdio<sup>4</sup>.</p>
    <p>As f&#237;stulas oriundas da coron&#225;ria direita s&#227;o mais frequentes (70%), podendo ocorrer tamb&#233;m na art&#233;ria coron&#225;ria esquerda ou em ambas as art&#233;rias. Geralmente, a drenagem &#233; feita para c&#226;maras de baixa press&#227;o<sup>3</sup>. Dessa forma, a comunica&#231;&#227;o com c&#226;maras direitas tem incid&#234;ncia maior, entre 39 e 41% para ventr&#237;culo direito, entre 26 e 33% para &#225;trio direito, entre 15 e 20% para a art&#233;ria pulmonar, o seio coronariano e a veia cava superior<sup>3,5</sup>. F&#237;stulas para VE s&#227;o muito raras, tendo incid&#234;ncia de apenas 3%<sup>6,7</sup>.</p>
    <p>As art&#233;rias coron&#225;rias se desenvolvem cedo na embriog&#234;nese, entre a 6&#170; e 8&#170; semanas. A primeira estrutura das art&#233;rias coron&#225;rias consiste de uma rede capilar mioc&#225;rdica, que &#233; formada de c&#233;lulas endoteliais. O sistema arterial coronariano forma-se ao redor do tronco arterioso, e a sua estrutura principal come&#231;a a se desenvolver mais na por&#231;&#227;o que ir&#225; se tornar a futura aorta, quando de sua biparti&#231;&#227;o unindo-se &#224; rede capilar mioc&#225;rdica<sup>6</sup>. As f&#237;stulas coronarianas podem se desenvolver quando h&#225; uma persist&#234;ncia de espa&#231;os e sinusoides intertrabeculares embrion&#225;rios, contudo, quando a art&#233;ria coron&#225;ria principal permanece aderida ao tronco da pulmonar, estamos diante de uma origem an&#244;mala de coron&#225;ria<sup>4,7,8</sup>.</p>
    <p>A fisiopatologia e o quadro cl&#237;nico dependem da magnitude do fluxo de sangue atrav&#233;s da f&#237;stula e de sua localiza&#231;&#227;o. A maioria dos portadores s&#227;o assintom&#225;ticos (55%)<sup>3 </sup>, entretanto, quando existe manifesta&#231;&#227;o cl&#237;nica, esta &#233; de insufici&#234;ncia card&#237;aca ou dispneia aos esfor&#231;os. Sopro cont&#237;nuo, superficial e intenso em localiza&#231;&#227;o cl&#225;ssica de canal arterial persistente pode ser um achado do exame f&#237;sico<sup>4,8</sup>. Tamb&#233;m podem ocorrer o fen&#244;meno de "fuga de fluxo coronariano" e a sintomatologia, em tais casos, seria precordialgia, ou sinais de isquemia ao eletrocardiograma convencional ou ao esfor&#231;o, como no caso observado. A manifesta&#231;&#227;o isqu&#234;mica n&#227;o depende do tamanho da f&#237;stula e tem sido descrita mesmo com pequeno fluxo<sup>5</sup>.</p>
    <p>O diagn&#243;stico diferencial das f&#237;stulas das art&#233;rias coron&#225;rias deve ser feito com persist&#234;ncia de canal arterial, insufici&#234;ncia a&#243;rtica, aneurisma de seio de Valsalva roto e f&#237;stula pulmonar ou de parede tor&#225;cica.</p>
    <p>As f&#237;stulas podem ser diagnosticadas por ecocardiografia, que pode visibilizar uma art&#233;ria coron&#225;ria dilatada, de onde a anomalia se origina, e a pr&#243;pria f&#237;stula, incluindo a entrada para uma c&#226;mara ou vaso, al&#233;m de um fluxo sist&#243;lico e diast&#243;lico turbulento cont&#237;nuo<sup>8</sup>. Contudo, a angiografia coronariana &#233; o m&#233;todo de escolha para o diagn&#243;stico, ainda que detalhes da rela&#231;&#227;o da f&#237;stula com outras estruturas possam n&#227;o ser revelados por esta t&#233;cnica<sup>2</sup>. Ainda assim, a angio-TC das art&#233;rias coron&#225;rias poder&#225; exercer um papel importante no diagn&#243;stico e na terap&#234;utica dessa patologia, afinal sua capacidade de descrever detalhes importantes da anatomia coronariana e sua rela&#231;&#227;o com as demais estruturas do cora&#231;&#227;o fazem dela um m&#233;todo diagn&#243;stico por imagem promissor para essa e outras aplica&#231;&#245;es cl&#237;nicas. Al&#233;m do que, integrar a angiotomografia com estudo da perfus&#227;o mioc&#225;rdica ao estresse <italic>SPECT</italic> &#233; uma op&#231;&#227;o que pode revelar ainda mais detalhes fisiopatol&#243;gicos ao diagn&#243;stico, revelando graus m&#237;nimos de isquemia<sup>2</sup>.</p>
    <p>Com rela&#231;&#227;o ao tratamento, embora especialistas recomendem a repara&#231;&#227;o mec&#226;nica da f&#237;stula (procedimento aberto ou percut&#226;neo), esta &#233; uma recomenda&#231;&#227;o a casos sintom&#225;ticos, n&#227;o existindo <italic>guidelines</italic> para assintom&#225;ticos. H&#225;, contudo, algumas publica&#231;&#245;es que recomendam a corre&#231;&#227;o, mesmo em pacientes assintom&#225;ticos, levando em considera&#231;&#227;o o tamanho e o di&#226;metro do defeito, visando prevenir doen&#231;a coronariana prematura no vaso afetado<sup>8</sup>. Pacientes idosos assintom&#225;ticos e minimamente sintom&#225;ticos parecem se beneficiar com terapia medicamentosa. Regimes recomendados incluem agentes antianginosos tradicionais, como betabloqueadores, aspirina e bloqueadores de canal de c&#225;lcio. Agentes vasodilatadores, como os nitratos, t&#234;m sido reportados como exacerbadores do fen&#244;meno de roubo coronariano, tendo contraindica&#231;&#227;o relativa nesses pacientes<sup>6</sup>.</p>
    <p>Pela casu&#237;stica relatada na literatura, n&#227;o se permite estabelecer conduta padronizada. N&#227;o h&#225; consenso se o tratamento cir&#250;rgico deve ser sempre realizado, pois n&#227;o se conhece com exatid&#227;o a evolu&#231;&#227;o natural da doen&#231;a, assim como a frequ&#234;ncia das complica&#231;&#245;es que podem ocorrer. O fechamento espont&#226;neo da f&#237;stula &#233; muito raro, por&#233;m descrito<sup>5</sup>. Alguns autores advogam que profilaxia para endocardite deva ser realizada nesses indiv&#237;duos<sup>4</sup>. O tratamento pode ser cir&#250;rgico ou percut&#226;neo, dependendo do fluxo, da isquemia e do risco de complica&#231;&#245;es<sup>5</sup>.</p>
    <p>
      <bold>Potencial Conflito de Interesses</bold>
    </p>
    <p>Declaro n&#227;o haver conflito de interesses pertinentes.</p>
    <p>
      <bold>Fontes de Financiamento</bold>
    </p>
    <p>O presente estudo n&#227;o teve fontes de financiamento externas.</p>
    <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>
    <p>
      <fn id="endb" fn-type="corresp">
        <label>
          <bold>Correspond&#234;ncia: </bold>
        </label>
        <p> Roberto Moreno Mendon&#231;a </p>
        <p> Rua Mipibu, 757, Apto 701 - Petr&#243;polis </p>
        <p> 59014-480 - Natal, RN - Brasil </p>
        <p> E-mail: </p>
        <p>
          <email xlink:href="moreno@natal.digi.com.br">moreno@natal.digi.com.br</email>
        </p>
      </fn>
    </p>
    <p> Artigo recebido em 01/05/10; revisado recebido em 03/08/10; aceito em 16/09/10.</p>
  </body>
  <back>
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  </back>
  <sub-article article-type="translation" id="TRen" xml:lang="en">
    <front-stub>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Case Report</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title xml:lang="en">Coronary fistula to the left ventricle: assessed by computed tomography</article-title>
      </title-group>
      <abstract xml:lang="en">
        <p>Coronary artery fistulas are rare and are most often diagnosed by echocardiography or by cine-angiocardiography. However, the computed tomography angiography (CTA) of coronary arteries has been gaining ground. The incidence of this disease is very low, with a more frequent occurrence of fistulas originating in the right coronary artery. There is a higher incidence of coronary artery fistulas to right heart chambers, with coronary artery fistulas to the left ventricle (LV) being rare. Treatment can be surgical or percutaneous. This report describes a case of coronary fistula to left ventricle diagnosed by CT angiography of coronary arteries in a hypertensive and asymptomatic 46-year-old male, who was tested positive for ischemia in an exercise test. The CT angiography ruled out coronary obstructive disease, but it revealed a coronary fistula to the left ventricular cavity.</p>
      </abstract>
      <kwd-group xml:lang="en">
        <kwd>Cardiovascular diseases</kwd>
        <kwd>arterio-arterial fistula</kwd>
        <kwd>heart ventricles</kwd>
        <kwd>diagnosis</kwd>
        <kwd>tomography, computed</kwd>
      </kwd-group>
    </front-stub>
    <body>
      <p>
        <bold>CASE REPORT</bold>
      </p>
      <p>
        <fn id="enda-body2">
          <label>
            <bold>Coronary fistula to the left ventricle: assessed by computed tomography</bold>
          </label>
          <p>
            <bold>Roberto Moreno Mendon&#231;a; Rodrigo Lima Bandeira; Fredson J. S. Fonseca; Robson Macedo Filho</bold>
          </p>
        </fn>
      </p>
      <p>Instituto de Radiologia de Natal - IRN; Natal; RN - Brasil</p>
      <p>Mailing Address</p>
      <p>
        <bold>ABSTRACT</bold>
      </p>
      <p>Coronary artery fistulas are rare and are most often diagnosed by echocardiography or by cine-angiocardiography. However, the computed tomography angiography (CTA) of coronary arteries has been gaining ground. The incidence of this disease is very low, with a more frequent occurrence of fistulas originating in the right coronary artery. There is a higher incidence of coronary artery fistulas to right heart chambers, with coronary artery fistulas to the left ventricle (LV) being rare. Treatment can be surgical or percutaneous.</p>
      <p> This report describes a case of coronary fistula to left ventricle diagnosed by CT angiography of coronary arteries in a hypertensive and asymptomatic 46-year-old male, who was tested positive for ischemia in an exercise test. The CT angiography ruled out coronary obstructive disease, but it revealed a coronary fistula to the left ventricular cavity.</p>
      <p><bold>Keywords: </bold>Cardiovascular diseases; arterio-arterial fistula; heart ventricles; diagnosis; tomography, computed.</p>
      <p>
        <bold>Introduction</bold>
      </p>
      <p>Coronary fistulae (CF) are direct connections from one or more coronary arteries to cardiac chambers or a large vessel<sup>1</sup>. Congenital anomalies are more common than acquired anomalies<sup>2</sup>, being found in up to 0.2% of routine cine-angiocardiography<sup>3</sup>.</p>
      <p>Most patients are asymptomatic<sup>3</sup>, but some people may experience the following symptoms: fatigue, dyspnea, palpitations and ischemic chest pain. By means of auscultation, it is possible to hear continuous murmurs that are similar to those of patent ductus arteriosus<sup>4</sup>.</p>
      <p>As additional propaedeutics, the ECG may be normal. The diagnosis is usually made by echocardiography, especially when there is dilation of the coronary artery involved or high output coronary flow<sup>5</sup>, with cine-angiocardiography being the gold standard for diagnosis, revealing anatomical details that are important to the treatment<sup>2</sup>. </p>
      <p>This report describes a rare case of coronary fistula to left ventricle diagnosed by CT angiography of coronary arteries.</p>
      <p>
        <bold>Case report</bold>
      </p>
      <p>It refers to a 46-year-old, obese, hypertensive and dyslipidemic male patient. In the physical examination, the patient's heart rate was regular at three different stages and the BP was 160 x 100 mmHg. At the outpatient clinic, in the examination for coronary artery disease (CAD), the patient was asymptomatic. </p>
      <p>The ischemic test result obtained by means of an exercise test was positive. Therefore, in order to rule out CAD, a CT angiography of the coronary arteries was carried out and it revealed markedly dilated and tortuous coronary arteries, besides a large fistula connecting the anterior descending artery to the right coronary artery and a single confluence for the LV cavity adjacent to the posterior mitral valve leaflet (Figures).</p>
      <p>
        <bold>Methods</bold>
      </p>
      <p>The examination and clinical history of the patient in the digital archive of images (PACS) were reviewed. The patient's authorization to use the images for a case report was obtained. </p>
      <p>The equipment used was manufactured by Philips Medical Systems - model Brilliance 16-MDCT.</p>
      <p>With the patient lying on his back, in respiratory pause (apnea of 15 seconds), in electrocardiographic (ECG) synchronization, 0.75-mm thick tomographic slices of the heart were obtained by using 80 ml of nonionic iodinated contrast (Optiray 350 mg/ml) in an infusion pump at 5 ml/second, followed by 40 ml of 0.9% saline solution, at the same infusion rate. The images were viewed in the workstation from Philips Medical Systems, Brilliance CT model. Multiplanar reconstructions (MPR), curved multiplanar reconstructions (Curved MPR) and 3D reconstructions with volume rendering technique (VR) were performed (<xref ref-type="fig" rid="en_a17fig01m-body2">Figures 1</xref> and <xref ref-type="fig" rid="en_a17fig02m-body2">2</xref>).</p>
      <p content-type="asset">
        <fig id="en_a17fig01m-body2">
          <graphic xlink:href="1678-4170-abc-97-04-0e82-00017-gf01-en.jpg"/></fig>
      </p>
      <p content-type="asset">
        <fig id="en_a17fig02m-body2">
          <graphic xlink:href="1678-4170-abc-97-04-0e82-00017-gf02-en.jpg"/></fig>
      </p>
      <p>
        <bold>Discussion</bold>
      </p>
      <p>The incidence of coronary fistula among congenital heart diseases is low, totaling only 0.2% to 0.4%. It was first described in 1886 and the first surgical correction was successfully performed in 1947<sup>1</sup>. The congenital origin is even more frequently seen than the acquired origin<sup>2</sup> and associated anomalies may occur. Associations with patent ductus arteriosus, tetralogy of Fallot, ventricular septal defect and acquired cardiopathies have already been described in the literature<sup>5</sup>. The acquired origins may be infectious, traumatic or iatrogenic<sup>2</sup>. There were also reports of coronary fistulas associated with permanent pacemaker electrodes by erosion, after cardiac surgery, coronary angioplasty or acute myocardial infarction<sup>4</sup>.</p>
      <p>The fistulas originated from the right coronary artery are more frequent (70%) and may also occur in the left coronary artery or in both arteries. Generally, drainage is carried out for low-pressure chambers<sup>3</sup>. Thus, the incidence of communication with right chambers is higher, between 39 and 41% for the right ventricle, between 26 and 33% for the right atrium, between 15 and 20% for the pulmonary artery, the coronary sinus and the superior vena cava<sup>3,5</sup>. Fistulas to the LV are very rare, with an incidence of only 3%<sup>6,7</sup>.</p>
      <p>The coronary arteries develop early in the embryogenesis, between the 6<sup>th</sup> and 8<sup>th</sup> weeks. The first structure of the coronary arteries consists of a myocardial capillary network, which is made up of endothelial cells. The coronary arterial system is formed around the truncus arteriosus, and its main structure begins to develop more in the portion that will become the future aorta, when its bipartition occurs and it joins the myocardial capillary network<sup>6</sup>. Coronary fistulae can develop when there is a persistence of embryonic intertrabecular spaces and sinusoids, however, when the main coronary artery remains attached to the pulmonary trunk, we are faced with an anomalous origin of coronary artery<sup> 4,7,8</sup>.</p>
      <p>The pathophysiology and clinical profile depend on the magnitude of the blood flow through the fistula and its location. Most patients are asymptomatic (55%)<sup>3</sup>. However, when there are clinical manifestations, such manifestations are related to heart failure or dyspnea on exertion. Continuous, superficial and intense murmur in a classic location of patent ductus arteriosus may be a finding of the physical examination<sup>4,8</sup>. The "coronary flow withdrawal" phenomenon may also occur and, in such cases, the symptoms would be chest pain or signs of ischemia detected by the conventional electrocardiogram or during exercise testing, such as in the case observed. The ischemic event is not dependent on the size of the fistula and it has been described even with a small flow<sup>5</sup>.</p>
      <p>The differential diagnosis of coronary artery fistula shall be made with patent ductus arteriosus, aortic insufficiency, sinus of Valsalva aneurysm and pulmonary or chest wall fistula.</p>
      <p>Fistulas can be diagnosed by echocardiography, which can display a dilated coronary artery, where the abnormality arises, and even the fistula itself, including the entrance to a chamber or vessel, in addition to a continuous turbulent systolic and diastolic flow<sup>8</sup>. However, coronary angiography is the method of choice for the diagnosis, although details of the relationship between the fistula and other structures cannot be revealed by this technique<sup>2</sup>. Still, the CT angiography of the coronary arteries may play an important role in the diagnosis and therapy of this pathology, because, due its ability to describe important details of the coronary anatomy and its relationship with other structures of the heart, it can be considered a promising diagnostic imaging method for this and other clinical applications. In addition, the combination of CT angiography with stress SPECT myocardial perfusion imaging study is an option that may reveal even more pathophysiological details in the diagnosis, revealing minimal degrees of ischemia<sup>2</sup>.</p>
      <p>With regard to treatment, although experts advise that the fistula be mechanically repaired (open or percutaneous procedure), this is recommended for symptomatic cases, with no guidelines for asymptomatic patients. However, there are some publications that recommend the correction even in asymptomatic patients, considering the size and diameter of the defect, in order to prevent premature coronary artery disease in the affected vessel<sup>8</sup>. Asymptomatic and minimally symptomatic elderly patients seem to benefit from drug therapy. Recommended regimens include traditional antianginal agents, such as beta blockers, aspirin and calcium channel blockers. Vasodilator agents, such as nitrates, have been reported to exacerbate the coronary steal phenomenon, being relatively contraindicated in the case of such patients<sup>6</sup>.</p>
      <p>Based on the cases reported in the literature, it is not possible to establish a standardized management. There is consensus that the surgical treatment should always be carried out, because we do not know exactly the natural progression of the disease, or the frequency of complications that may occur. The spontaneous closure of the fistula is very rare, but it has been described<sup>5</sup>. Some authors argue that endocarditis prophylaxis should be carried out in such individuals<sup>4</sup>. The treatment can be surgical or percutaneous, depending on the flow, ischemia and complication risks<sup>5</sup>.</p>
      <p>
        <bold>Potential Conflict of Interest</bold>
      </p>
      <p>No potential conflict of interest relevant to this article was reported.</p>
      <p>
        <bold>Sources of Funding</bold>
      </p>
      <p>There were no external funding sources for this study.</p>
      <p>
        <bold>Study Association</bold>
      </p>
      <p>This study is not associated with any post-graduation program.</p>
      <p>
        <bold>References</bold>
      </p>
    </body>
  </sub-article>
  <sub-article article-type="translation" id="TRes" xml:lang="es">
    <front-stub>
      <article-categories/>
      <title-group>
        <article-title xml:lang="es">F&#237;stula coronaria para ventr&#237;culo izquierdo: diagn&#243;stico por tomograf&#237;a computarizada</article-title>
      </title-group>
      <abstract xml:lang="es">
        <p>F&#237;stulas de arterias coronarias son raras, siendo diagnosticadas m&#225;s frecuentemente por el ecocardiograma o por la cineangiocoronariograf&#237;a, entre tanto, la angiotomograf&#237;a computarizada (angio-TC) de las coronarias gana espacio. Esa patolog&#237;a presenta incidencia baj&#237;sima, siendo las f&#237;stulas originadas de la coronaria derecha m&#225;s frecuentes. F&#237;stulas coronarias para c&#225;maras card&#237;acas derechas son m&#225;s incidentes, siendo raras para el ventr&#237;culo izquierdo (VI). El tratamiento puede ser quir&#250;rgico o percut&#225;neo. Este relato describe caso de f&#237;stula coronaria para VI diagnosticada por la angio-TC de las coronarias en hombre de 46 a&#241;os, hipertenso, asintom&#225;tico con test ergom&#233;trico positivo para isquemia. Angio-TC de coronarias descart&#243; enfermedad obstructiva, sin embargo revel&#243; f&#237;stula coronaria conect&#225;ndose con cavidad ventricular izquierda.</p>
      </abstract>
      <kwd-group xml:lang="es">
        <kwd>Enfermedades cardiovasculares</kwd>
        <kwd>f&#237;stula arterio-arterial</kwd>
        <kwd>ventr&#237;culos del coraz&#243;n</kwd>
        <kwd>diagn&#243;stico</kwd>
        <kwd>tomograf&#237;a computarizada</kwd>
      </kwd-group>
    </front-stub>
    <body>
      <p>
        <bold>CASO CL&#205;NICO</bold>
      </p>
      <p>
        <fn id="enda-body3">
          <label>
            <bold>F&#237;stula coronaria para ventr&#237;culo izquierdo: diagn&#243;stico por tomograf&#237;a computarizada</bold>
          </label>
          <p>
            <bold>Roberto Moreno Mendon&#231;a; Rodrigo Lima Bandeira; Fredson J. S. Fonseca; Robson Macedo Filho</bold>
          </p>
        </fn>
      </p>
      <p>Instituto de Radiologia de Natal - IRN; Natal; RN - Brasil</p>
      <p>Correspondencia</p>
      <p>
        <bold>RESUMEN</bold>
      </p>
      <p>F&#237;stulas de arterias coronarias son raras, siendo diagnosticadas m&#225;s frecuentemente por el ecocardiograma o por la cineangiocoronariograf&#237;a, entre tanto, la angiotomograf&#237;a computarizada (angio-TC) de las coronarias gana espacio. Esa patolog&#237;a presenta incidencia baj&#237;sima, siendo las f&#237;stulas originadas de la coronaria derecha m&#225;s frecuentes. F&#237;stulas coronarias para c&#225;maras card&#237;acas derechas son m&#225;s incidentes, siendo raras para el ventr&#237;culo izquierdo (VI). El tratamiento puede ser quir&#250;rgico o percut&#225;neo. </p>
      <p> Este relato describe caso de f&#237;stula coronaria para VI diagnosticada por la angio-TC de las coronarias en hombre de 46 a&#241;os, hipertenso, asintom&#225;tico con test ergom&#233;trico positivo para isquemia. Angio-TC de coronarias descart&#243; enfermedad obstructiva, sin embargo revel&#243; f&#237;stula coronaria conect&#225;ndose con cavidad ventricular izquierda. </p>
      <p><bold>Palabras clave: </bold>Enfermedades cardiovasculares, f&#237;stula arterio-arterial, ventr&#237;culos del coraz&#243;n, diagn&#243;stico, tomograf&#237;a computarizada.</p>
      <p>
        <bold>Introducci&#243;n</bold>
      </p>
      <p>Las f&#237;stulas coronarias (FC) son conexiones directas de una o m&#225;s arterias coronarias a c&#225;maras card&#237;acas o gran vaso<sup>1</sup>. Las anomal&#237;as cong&#233;nitas son m&#225;s comunes que las adquiridas<sup>2</sup>, siendo encontradas en hasta 0,2% de las cineangiocoronariograf&#237;as de rutina<sup>3</sup>.</p>
      <p>La mayor&#237;a de los pacientes es asintom&#225;tica<sup>3</sup>, pero, cuando presenta s&#237;ntomas, estos pueden ser: fatiga, disnea de esfuerzo, palpitaciones y dolor tor&#225;cico isqu&#233;mico. Soplos continuos pueden ser auscultados, siendo semejantes al de un canal arterial patente<sup>4</sup>.</p>
      <p>Como proped&#233;utica complementaria, la electrocardiograf&#237;a puede ser normal. Generalmente, el diagn&#243;stico es realizado por el ecocardiograma, especialmente cuando hay dilataci&#243;n de la arteria coronaria envuelta o flujo coronario de alto d&#233;bito<sup>5</sup>, siendo la cineangiocoronariograf&#237;a el <italic>gold standard</italic> para el diagn&#243;stico, revelando detalles anat&#243;micos importantes para el tratamiento<sup>2</sup>. </p>
      <p>Este relato describe un caso raro de f&#237;stula coronaria para el VI diagnosticada por la angio-TC de las arterias coronarias.</p>
      <p>
        <bold>Relato del caso</bold>
      </p>
      <p>Se trata de paciente masculino, con 46 a&#241;os, obeso, hipertenso y dislipid&#233;mico. Al examen f&#237;sico, el mismo presentaba ritmo card&#237;aco regular en tres tiempos, PA: 160 x 100 mmHg. Se encontraba asintom&#225;tico en investigaci&#243;n ambulatoria para enfermedad arterial coronaria (EAC). </p>
      <p>La prueba isqu&#233;mica obtenida por medio de test ergom&#233;trico fue positiva. Entonces, con la finalidad de excluir EAC, se realiz&#243; una angio-TC de las arterias coronarias, que revel&#243; arterias coronarias acentuadamente dilatadas y tortuosas, adem&#225;s de gran f&#237;stula conectando la arteria descendente anterior con la coronaria derecha y desembocadura &#250;nica para la cavidad del VI, adyacente a la hoja posterior de la v&#225;lvula mitral (Figuras).</p>
      <p>
        <bold>M&#233;todos</bold>
      </p>
      <p>Se revisaron el examen y la historia cl&#237;nica del paciente en el archivo digital de im&#225;genes (PACS). Se obtuvo la autorizaci&#243;n del paciente para la utilizaci&#243;n de las im&#225;genes para relato de caso. </p>
      <p>El equipamiento utilizado fue el de la <italic>Philips Medical Systems</italic> modelo <italic>Brilliance 16-MDCT</italic>.</p>
      <p>Con el paciente en dec&#250;bito dorsal, en pausa respiratoria (apnea de 15 segundos), bajo sincronizaci&#243;n electrocardiogr&#225;fica (ECG), cortes tomogr&#225;ficos del coraz&#243;n con 0,75 mm de espesor fueron obtenidos, utilizando 80 ml de contraste yodado no i&#243;nico (Optiray 350 mg/ml) en bomba de infusi&#243;n a 5 ml/seg&#250;n, seguido de 40 ml de suero fisiol&#243;gico 0,9% con la misma velocidad de infusi&#243;n. Las im&#225;genes fueron visualizadas en estaci&#243;n de trabajo de la <italic>Philips Medical Systems </italic>modelo <italic>Brilliance CT</italic>. Fueron realizadas reformataciones multiplanares (MPR), multiplanares curvo (MPRc) y reconstrucciones en 3D con t&#233;cnica de <italic>volumenrendering</italic> (VR) (<xref ref-type="fig" rid="es_a17fig01m-body3">Figuras 1</xref> y <xref ref-type="fig" rid="es_a17fig02m-body3">2</xref>).</p>
      <p content-type="asset">
        <fig id="es_a17fig01m-body3">
          <graphic xlink:href="1678-4170-abc-97-04-0e82-00017-gf01-es.jpg"/></fig>
      </p>
      <p content-type="asset">
        <fig id="es_a17fig02m-body3">
          <graphic xlink:href="1678-4170-abc-97-04-0e82-00017-gf02-es.jpg"/></fig>
      </p>
      <p>
        <bold>Discusi&#243;n</bold>
      </p>
      <p>La incidencia de f&#237;stula coronaria entre las cardiopat&#237;as cong&#233;nitas es baja, totalizando apenas 0,2% a 0,4%. Fue descripta por primera vez en 1886 y la primera correcci&#243;n quir&#250;rgica con &#233;xito fue realizada en 1947<sup>1</sup>. El origen cong&#233;nito es aun m&#225;s observado que la adquirida<sup>2</sup> y anomal&#237;as asociadas pueden ocurrir, siendo descriptas en la literatura asociaciones con persistencia de canal arterial, tetralog&#237;a de Fallot, comunicaci&#243;n interventricular y aun cardiopat&#237;as adquiridas<sup>5</sup>. Las adquiridas pueden ser infecciosas, traum&#225;ticas o iatrog&#233;nicas<sup>2</sup>. Hay relatos tambi&#233;n de f&#237;stulas coronarias asociadas a electrodos permanentes de marcapasos por erosi&#243;n, despu&#233;s de cirug&#237;a card&#237;aca, angioplastia coronaria o infarto agudo de miocardio<sup>4</sup>.</p>
      <p>Las f&#237;stulas oriundas de la coronaria derecha son m&#225;s frecuentes (70%), pudiendo ocurrir tambi&#233;n en la arteria coronaria izquierda o en ambas arterias. Generalmente, el drenaje es hecho para c&#225;maras de baja presi&#243;n<sup>3</sup>. De esa forma, la comunicaci&#243;n con c&#225;maras derechas tiene incidencia mayor, entre 39 y 41% para ventr&#237;culo derecho, entre 26 y 33% para atrio derecho, entre 15 y 20% para la arteria pulmonar, el seno coronario y la vena cava superior<sup>3,5</sup>. F&#237;stulas para VI son muy raras, teniendo incidencia de apenas 3%<sup>6,7</sup>.</p>
      <p>Las arterias coronarias se desarrollan temprano en la embriog&#233;nesis, entre la 6&#170; y 8&#170; semanas. La primera estructura de las arterias coronarias consiste en una red capilar mioc&#225;rdica, que es formada de c&#233;lulas endoteliales. El sistema arterial coronario se forma alrededor del tronco arterioso, y su estructura principal comienza a desarrollarse m&#225;s en la porci&#243;n que se volver&#225; la futura aorta, cuando ocurra su bipartici&#243;n uni&#233;ndose a la red capilar mioc&#225;rdica<sup>6</sup>. Las f&#237;stulas coronarias pueden desarrollarse cuando hay una persistencia de espacios y sinusoides intertrabeculares embrionarios, con todo, cuando la arteria coronaria principal permanece adherida al tronco de la pulmonar, estamos delante de un origen an&#243;malo de coronaria<sup>4,7,8</sup>.</p>
      <p>La fisiopatolog&#237;a y el cuadro cl&#237;nico dependen de la magnitud del flujo de sangre a trav&#233;s de la f&#237;stula y de su ubicaci&#243;n. La mayor&#237;a de los portadores son asintom&#225;ticos (55%)<sup>3 </sup>, entre tanto, cuando existe manifestaci&#243;n cl&#237;nica, esta es de insuficiencia card&#237;aca o disnea a los esfuerzos. Soplo continuo, superficial e intenso en ubicaci&#243;n cl&#225;sica de canal arterial persistente puede ser un hallazgo del examen f&#237;sico<sup>4,8</sup>. Tambi&#233;n pueden ocurrir el fen&#243;meno de "fuga de flujo coronario" y la sintomatolog&#237;a, en tales casos, ser&#237;a precordialgia, o se&#241;ales de isquemia al electrocardiograma convencional o al esfuerzo, como en el caso observado. La manifestaci&#243;n isqu&#233;mica no depende del tama&#241;o de la f&#237;stula y ha sido descripta aun con peque&#241;o flujo<sup>5</sup>.</p>
      <p>El diagn&#243;stico diferencial de las f&#237;stulas de las arterias coronarias debe ser hecho con persistencia de canal arterial, insuficiencia a&#243;rtica, aneurisma de seno de Valsalva roto y f&#237;stula pulmonar o de pared tor&#225;cica.</p>
      <p>Las f&#237;stulas pueden ser diagnosticadas por ecocardiograf&#237;a, que puede visualizar una arteria coronaria dilatada, de donde la anomal&#237;a se origina, y la propia f&#237;stula, incluyendo la entrada a una c&#225;mara o vaso, adem&#225;s de un flujo sist&#243;lico y diast&#243;lico turbulento continuo<sup>8</sup>. Con todo, la angiograf&#237;a coronaria es el m&#233;todo de elecci&#243;n para el diagn&#243;stico, aunque detalles de la relaci&#243;n de la f&#237;stula con otras estructuras puedan no ser revelados por esta t&#233;cnica<sup>2</sup>. Aun as&#237;, la angio-TC de las arterias coronarias podr&#225; ejercer un papel importante en el diagn&#243;stico y en la terap&#233;utica de esa patolog&#237;a, al final su capacidad de describir detalles importantes de la anatom&#237;a coronaria y su relaci&#243;n con las dem&#225;s estructuras del coraz&#243;n hacen de ella un m&#233;todo diagn&#243;stico por imagen promisorio para esa y otras aplicaciones cl&#237;nicas. Adem&#225;s de que, integrar la angiotomograf&#237;a con estudio de la perfusi&#243;n mioc&#225;rdica al estr&#233;s <italic>SPECT</italic> es una opci&#243;n que puede revelar aun m&#225;s detalles fisiopatol&#243;gicos al diagn&#243;stico, revelando grados m&#237;nimos de isquemia<sup>2</sup>.</p>
      <p>Con relaci&#243;n al tratamiento, aunque especialistas recomienden la reparaci&#243;n mec&#225;nica de la f&#237;stula (procedimiento abierto o percut&#225;neo), esta es una recomendaci&#243;n a casos sintom&#225;ticos, no existiendo <italic>guidelines</italic> para asintom&#225;ticos. Hay, con todo, algunas publicaciones que recomiendan la correcci&#243;n, aun en pacientes asintom&#225;ticos, teniendo en consideraci&#243;n el tama&#241;o y el di&#225;metro del defecto, buscando prevenir enfermedad coronaria prematura en el vaso afectado<sup>8</sup>. Pacientes a&#241;osos asintom&#225;ticos y m&#237;nimamente sintom&#225;ticos parecen beneficiarse con terapia medicamentosa. Reg&#237;menes recomendados incluyen agentes antianginosos tradicionales, como betabloqueantes, aspirina y bloqueadores de canal de calcio. Agentes vasodilatadores, como los nitratos, han sido reportados como exacerbadores del fen&#243;meno de robo coronario, teniendo contraindicaci&#243;n relativa en esos pacientes<sup>6</sup>.</p>
      <p>Por la casu&#237;stica relatada en la literatura, no se permite establecer conducta estandarizada. No hay consenso sobre si el tratamiento quir&#250;rgico debe ser siempre realizado, pues no se conoce con exactitud la evoluci&#243;n natural de la enfermedad, as&#237; como la frecuencia de las complicaciones que pueden ocurrir. El cierre espont&#225;neo de la f&#237;stula es muy raro, sin embargo descripto<sup>5</sup>. Algunos autores abogan que deba ser realizada profilaxia para endocarditis en esos individuos<sup>4</sup>. El tratamiento puede ser quir&#250;rgico o percut&#225;neo, dependiendo del flujo, de la isquemia y del riesgo de complicaciones<sup>5</sup>.</p>
      <p>
        <bold>Potencial Conflicto de Intereses</bold>
      </p>
      <p>Declaro no haber conflicto de intereses pertinentes.</p>
      <p>
        <bold>Fuentes de Financiaci&#243;n</bold>
      </p>
      <p>El presente estudio no tuve fuentes de financiaci&#243;n externas.</p>
      <p>
        <bold>Vinculaci&#243;n Acad&#233;mica</bold>
      </p>
      <p>No hay vinculaci&#243;n de este estudio a programas de postgrado.</p>
      <p>
        <bold>Referencias</bold>
      </p>
    </body>
  </sub-article>
</article>
