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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">vgx8sJKY6RPKLR9pprYw6pk</article-id>
      <article-id pub-id-type="other">00028</article-id>
      <article-id pub-id-type="publisher-id" specific-use="scielo-v2">S0066-782X2009001200028</article-id>
      <article-id pub-id-type="publisher-id" specific-use="scielo-v1">S0066-782X(09)09300628</article-id>
      <article-id pub-id-type="doi">10.1590/S0066-782X2009001200028</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Comunica&#231;&#227;o Breve</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Cardiopatia chag&#225;sica cr&#244;nica na Amaz&#244;nia: uma etiologia a ser lembrada</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Ferreira</surname>
            <given-names>Jo&#227;o Marcos Bemfica Barbosa</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Guerra</surname>
            <given-names>Jorge Augusto de Oliveira</given-names>
          </name>
          <xref ref-type="aff" rid="aff02"/>
          <xref ref-type="aff" rid="aff03"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Magalh&#227;es</surname>
            <given-names>Belisa Maria Lopes</given-names>
          </name>
          <xref ref-type="aff" rid="aff03"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Coelho</surname>
            <given-names>Le&#237;la I. A. R. C.</given-names>
          </name>
          <xref ref-type="aff" rid="aff02"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Maciel</surname>
            <given-names>Marcel Gon&#231;alves</given-names>
          </name>
          <xref ref-type="aff" rid="aff03"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Barbosa</surname>
            <given-names>Maria das Gra&#231;as Vale</given-names>
          </name>
          <xref ref-type="aff" rid="aff02"/>
          <xref ref-type="aff" rid="aff03"/>
        </contrib>
      </contrib-group>
      <aff id="aff02">
        <addr-line>
          <named-content content-type="state"/>
        </addr-line>
        <institution content-type="orgname">Funda&#231;&#227;o de Medicina Tropical Doutor Heitor Vieira Dourado</institution>
        <country country="BR">Brazil</country>
      </aff>
      <aff id="aff01">
        <addr-line>
          <named-content content-type="city">Manaus</named-content>
          <named-content content-type="state">AM</named-content>
        </addr-line>
        <institution content-type="orgname">Hospital Universit&#225;rio Francisca Mendes</institution>
        <country country="BR">Brasil</country>
      </aff>
      <aff id="aff03">
        <addr-line>
          <named-content content-type="city">Manaus</named-content>
          <named-content content-type="state"/>
        </addr-line>
        <institution content-type="orgname">Universidade do Estado do Amazonas</institution>
        <country country="BR">Brazil</country>
      </aff>
      <pub-date date-type="collection" publication-format="electronic">
        <month>12</month>
        <year>2009</year>
      </pub-date>
      <volume>93</volume>
      <issue>6</issue>
      <fpage>e107</fpage>
      <lpage>e109</lpage>
      <history>
        <date date-type="accepted">
          <day>03</day>
          <month>07</month>
          <year>2009</year>
        </date>
        <date date-type="rev-recd">
          <day>18</day>
          <month>05</month>
          <year>2009</year>
        </date>
        <date date-type="received">
          <day>05</day>
          <month>01</month>
          <year>2009</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>Este estudo avaliou a frequ&#234;ncia de cardiopatia chag&#225;sica cr&#244;nica (CCC) em 37 pacientes aut&#243;ctones da Amaz&#244;nia com disfun&#231;&#227;o sist&#243;lica ventricular esquerda sem etiologia definida. Foram diagnosticados tr&#234;s casos com frequ&#234;ncia de 8,1% no grupo estudado.</p>
      </abstract>
      <kwd-group xml:lang="pt" kwd-group-type="author-generated">
        <kwd>Frequ&#234;ncia</kwd>
        <kwd>cardiomiopatia chag&#225;sica</kwd>
        <kwd>Amaz&#244;nia</kwd>
      </kwd-group>
      <pub-date publication-format="electronic" date-type="pub">
        <day>05</day>
        <month>05</month>
        <year>2010</year>
      </pub-date>
    </article-meta>
  </front>
  <body>
    <p>
      <bold>COMUNICA&#199;&#195;O BREVE</bold>
    </p>
    <p>
      <bold>Cardiopatia chag&#225;sica cr&#244;nica na Amaz&#244;nia: uma etiologia a ser lembrada</bold>
    </p>
    <p>
      <bold>Jo&#227;o Marcos Bemfica Barbosa Ferreira<sup>I</sup>; Jorge Augusto de Oliveira Guerra<sup>II, III</sup>; Belisa Maria Lopes Magalh&#227;es<sup>III</sup>; Le&#237;la I. A. R. C. Coelho<sup>II</sup>; Marcel Gon&#231;alves Maciel<sup>III</sup>; Maria das Gra&#231;as Vale Barbosa<sup>II, III</sup></bold>
    </p>
    <p><sup>I</sup>Hospital Universit&#225;rio Francisca Mendes (UFAM), Manaus, AM - Brasil </p>
    <p><sup>II</sup>Funda&#231;&#227;o de Medicina Tropical do Amazonas, Manaus, AM - Brasil </p>
    <p><sup>III</sup>Universidade do Estado do Amazonas, Manaus, AM - Brasil</p>
    <p>
      <xref ref-type="corresp" rid="back">Correspond&#234;ncia</xref>
    </p>
    <p>
      <bold>RESUMO</bold>
    </p>
    <p>Este estudo avaliou a frequ&#234;ncia de cardiopatia chag&#225;sica cr&#244;nica (CCC) em 37 pacientes aut&#243;ctones da Amaz&#244;nia com disfun&#231;&#227;o sist&#243;lica ventricular esquerda sem etiologia definida. Foram diagnosticados tr&#234;s casos com frequ&#234;ncia de 8,1% no grupo estudado.</p>
    <p><bold>Palavras chave: </bold> Frequ&#234;ncia; cardiomiopatia chag&#225;sica; Amaz&#244;nia</p>
    <p>
      <bold>Introdu&#231;&#227;o</bold>
    </p>
    <p>A Amaz&#244;nia foi por muitos anos considerada &#225;rea de baixo risco para a doen&#231;a de Chagas (DC). Recentemente, tem sido mais frequente o diagn&#243;stico tanto de casos agudos como cr&#244;nicos na regi&#227;o<sup>1</sup>. Existem, por&#233;m, relatos de apenas cinco casos cr&#244;nicos com miocardiopatia dilatada de etiologia chag&#225;sica em aut&#243;ctones da Amaz&#244;nia<sup>2,3</sup>.</p>
    <p>N&#227;o existem estudos que avaliem a frequ&#234;ncia de DC em pacientes com miocardiopatia dilatada na Amaz&#244;nia. Em outras &#225;reas, a DC responde por uma parcela significativa dos casos. No entanto, essa etiologia raramente &#233; lembrada em pacientes aut&#243;ctones da Amaz&#244;nia, n&#227;o se realizando a sorologia para <italic>Trypanosoma cruzi,</italic> o que pode subestimar o diagn&#243;stico da doen&#231;a.</p>
    <p>O objetivo deste estudo foi avaliar a frequ&#234;ncia da cardiopatia chag&#225;sica cr&#244;nica (CCC) em pacientes aut&#243;ctones da Amaz&#244;nia com miocardiopatia dilatada e disfun&#231;&#227;o sist&#243;lica ventricular esquerda sem etiologia definida.</p>
    <p>
      <bold>M&#233;todos</bold>
    </p>
    <p>Estudo prospectivo e transversal com avalia&#231;&#227;o de 37 pacientes que realizaram ecocardiograma transtor&#225;cico entre julho e dezembro de 2007, no Hospital Universit&#225;rio Francisca Mendes da Universidade Federal do Amazonas.</p>
    <p>Foi escolhido o Hospital Universit&#225;rio Francisca Mendes por se tratar do &#250;nico Centro de Refer&#234;ncia de Alta Complexidade em Cardiologia credenciado pelo SUS no estado do Amazonas. Este servi&#231;o atende pacientes de todo o estado do Amazonas e de outros estados da Amaz&#244;nia Ocidental.</p>
    <p>Foram inclu&#237;dos pacientes de ambos os sexos, com idade superior a 12 anos e fra&#231;&#227;o de eje&#231;&#227;o <underline>&lt;</underline> 45% no ecocardiograma transtor&#225;cico, sendo todos aut&#243;ctones da Amaz&#244;nia.</p>
    <p>Foram considerados como aut&#243;ctones aqueles naturais da Amaz&#244;nia Brasileira, sem qualquer viagem pr&#233;via para outras regi&#245;es.</p>
    <p>Foram exclu&#237;dos aqueles com evid&#234;ncias de coronariopatia, hipertens&#227;o arterial, valvopatias ou cardiopatias cong&#234;nitas.</p>
    <p>O estudo foi aprovado pelos Comit&#234;s de &#201;tica em Pequisa da Universidade Federal do Amazonas e da Funda&#231;&#227;o de Medicina Tropical do Amazonas. Os pacientes assinaram termo de consentimento livre e esclarecido.</p>
    <p>Foi realizada sorologia para DC com pesquisa de IgG pelos m&#233;todos de Imunofluoresc&#234;ncia Indireta e ELISA na Funda&#231;&#227;o de Medicina Tropical do Amazonas.</p>
    <p>A Imunofluoresc&#234;ncia Indireta foi realizada com kit de Biomanguinhos (Funda&#231;&#227;o Oswaldo Cruz)<sup>4</sup> e o m&#233;todo ELISA, com ant&#237;geno recombinante (Pathozyme Chagas<sup>&#174;</sup>)<sup>5</sup>.</p>
    <p>Os pacientes com um ou dois m&#233;todos reagentes realizaram Western-Blot (TESA-BLOT)<sup>6</sup>.</p>
    <p>Foram considerados com cardiopatia chag&#225;sica cr&#244;nica aqueles com dois m&#233;todos reagentes.</p>
    <p>
      <bold>Resultados</bold>
    </p>
    <p>No per&#237;odo do estudo, foram realizados 2.039 exames de ecocardiograma transtor&#225;cico, com 196 pacientes apresentando fra&#231;&#227;o de eje&#231;&#227;o de VE <underline>&lt;</underline> 45%.</p>
    <p>Ap&#243;s avalia&#231;&#227;o dos crit&#233;rios de inclus&#227;o e exclus&#227;o, 37 pacientes foram inclu&#237;dos no estudo (m&#233;dia de idade de 62,9 anos, 81% do sexo masculino). A m&#233;dia da fra&#231;&#227;o de eje&#231;&#227;o do VE foi de 29,4%.</p>
    <p>A naturalidade dos pacientes foi de 43,2% do interior do Amazonas; 35,1% do munic&#237;pio de Manaus (AM); 13,5 % do Par&#225;; 5,4% do Maranh&#227;o e 2,7% do Acre.</p>
    <p>A imunofluoresc&#234;ncia indireta foi reagente em oito casos (21,6%), o ELISA em dois (5,4%) e o Western-Blot em tr&#234;s (8,1%).</p>
    <p>Tr&#234;s pacientes tiveram o diagn&#243;stico de CCC. A frequ&#234;ncia de CCC na popula&#231;&#227;o estudada foi de 8,1%.</p>
    <p>Os dados dos pacientes positivos est&#227;o descritos na <xref ref-type="table" rid="t1">Tabela 1</xref>.</p>
    <p content-type="asset">
      <table-wrap id="t1">
        <graphic xlink:href="1678-4170-abc-93-06-e107-00028-gt01.jpg"/></table-wrap>
    </p>
    <p>
      <bold>Discuss&#227;o</bold>
    </p>
    <p>A Amaz&#244;nia &#233; considerada hipoend&#234;mica para DC. Recentemente t&#234;m ocorrido casos agudos em surtos ou isolados, sendo relatados aproximadamente 440 casos na regi&#227;o. Com rela&#231;&#227;o aos casos cr&#244;nicos, a taxa de soropositividade &#233; de 1% a 3%, com risco maior em certas subregi&#245;es<sup>1</sup>.</p>
    <p>Uma destas subregi&#245;es &#233; o munic&#237;pio de Barcelos, na microrregi&#227;o do Rio Negro (AM). Neste local foi descrita transmiss&#227;o relacionada &#224; extra&#231;&#227;o de fibras de pia&#231;aba. Tr&#234;s inqu&#233;ritos feitos entre 1991 e 1997, envolvendo 2.254 indiv&#237;duos de Barcelos, mostraram preval&#234;ncia de 2,8% a 5% de sorologias positivas confirmadas com ELISA recombinante e Western Blot<sup>7,8</sup>.</p>
    <p>Com rela&#231;&#227;o ao agente etiol&#243;gico, tem sido descrito na Amaz&#244;nia o <italic>T. cruzi</italic> dos grupos zimodema 1, zimodema 3 ou h&#237;brido Z1/Z3. Estas cepas s&#227;o diferentes das encontradas nas zonas end&#234;micas do Brasil onde predomina o zimodema 2<sup>1</sup>. N&#227;o se conhece totalmente a patogenicidade das cepas da Amaz&#244;nia; por&#233;m, acredita-se que causem baixa morbidade, provavelmente menor que a encontrada nas &#225;reas end&#234;micas<sup>1,2</sup>.</p>
    <p>Apesar disso, foram descritos dois casos fatais de miocardiopatia dilatada e tr&#234;s casos com altera&#231;&#245;es ecocardiogr&#225;ficas t&#237;picas de DC em pacientes com infec&#231;&#227;o chag&#225;sica cr&#244;nica em Barcelos (AM)<sup>2,3</sup>.</p>
    <p>Ainda n&#227;o conhecemos totalmente a import&#226;ncia da DC como causa de miocardiopatia dilatada na Amaz&#244;nia. Em &#225;reas end&#234;micas, a frequ&#234;ncia &#233; vari&#225;vel, por&#233;m significante. O presente estudo com frequ&#234;ncia de 8,1% em pacientes sem etiologia definida demonstra que a cardiopatia chag&#225;sica &#233; uma causa importante de insufici&#234;ncia card&#237;aca na regi&#227;o amaz&#244;nica.</p>
    <p>A hist&#243;ria epidemiol&#243;gica de dois pacientes &#233; compat&#237;vel com DC. O primeiro paciente trabalhou tr&#234;s anos com extra&#231;&#227;o de pia&#231;aba no munic&#237;pio de Barcelos (AM). O segundo paciente mora atualmente no assentamento Tarum&#227;-Mirim em Manaus (AM) e trabalhou doze anos em seringal no Rio Purus (AM) (<xref ref-type="fig" rid="f1">Figura</xref>) 1. Nestes tr&#234;s locais foi relatada a presen&#231;a de vetores infectados, de reservat&#243;rios silvestres e de casos de infec&#231;&#227;o humana<sup>7-10</sup>. O terceiro paciente &#233; procedente de Iranduba (AM) onde n&#227;o existem estudos relacionados a DC. &#201; importante destacar que esses tr&#234;s pacientes procediam de munic&#237;pios do interior do Amazonas.</p>
    <p content-type="asset">
      <fig id="f1">
        <graphic xlink:href="1678-4170-abc-93-06-e107-00028-gf01.jpg"/></fig>
    </p>
    <p>
      <bold>Conclus&#227;o</bold>
    </p>
    <p>O presente estudo sugere que a DC &#233; uma etiologia significativa de miocardiopatia dilatada na regi&#227;o amaz&#244;nica, sendo importante sua pesquisa nos pacientes aut&#243;ctones. Por&#233;m s&#227;o necess&#225;rios estudos com maior casu&#237;stica para se conhecer melhor a import&#226;ncia da DC como etiologia das cardiopatias na Amaz&#244;nia.</p>
    <p>
      <bold>Agradecimentos</bold>
    </p>
    <p>A Dra. Eufrozina Setsu Umezawa e Norival Kesper J&#250;nior do Instituto de Medicina Tropical de S&#227;o Paulo, pela realiza&#231;&#227;o do Western-Blot. Ao Dr. F&#225;bio Fernandes, do Instituto do Cora&#231;&#227;o da Universidade de S&#227;o Paulo, pela leitura do artigo e sugest&#245;es realizadas.</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="back" fn-type="corresp">
        <p>Correspond&#234;ncia:</p>
        <p> Jo&#227;o Marcos B. Barbosa Ferreira </p>
        <p> Rua Ramos Ferreira n&#250;mero 199, Apartamento 1501 - Aparecida </p>
        <p> 69010-120 - Manaus, AM - Brasil </p>
        <p> E-mail: </p>
        <p>
          <email xlink:href="jmbemfica@hotmail.com">jmbemfica@hotmail.com</email>
        </p>
      </fn>
    </p>
    <p>Artigo recebido em 05/01/09; revisado recebido em 18/05/09; aceito em 03/07/09</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>Brief Communication</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title xml:lang="en">Chronic chagasic cardiopathy in Amazon region: an etiology to remember</article-title>
      </title-group>
      <abstract xml:lang="en">
        <p>This study assessed the frequency of chronic chagasic cardiopathy (CCC) in 37 autochthonus patients from Amazon region with left ventricular systolic dysfunction of undefined etiology. Three cases were diagnosed in the studied sample, with an 8.1% frequency.</p>
      </abstract>
      <kwd-group xml:lang="en">
        <kwd>Frequency</kwd>
        <kwd>chagas cardiomyopathy</kwd>
        <kwd>Amazon region</kwd>
      </kwd-group>
    </front-stub>
    <body>
      <p>
        <bold>BRIEF COMMUNICATION</bold>
      </p>
      <p>
        <fn id="top-body2">
          <label>
            <bold>Chronic chagasic cardiopathy in Amazon Region: an etiology to remember</bold>
          </label>
          <p>
            <bold>Jo&#227;o Marcos Bemfica Barbosa Ferreira<sup>I</sup>; Jorge Augusto de Oliveira Guerra<sup>II, III</sup>; Belisa Maria Lopes Magalh&#227;es<sup>III</sup>; Le&#237;la I. A. R. C. Coelho<sup>II</sup>; Marcel Gon&#231;alves Maciel<sup>III</sup>; Maria das Gra&#231;as Vale Barbosa<sup>II, III</sup></bold>
          </p>
        </fn>
      </p>
      <p><sup>I</sup>Hospital Universit&#225;rio Francisca Mendes (UFAM)</p>
      <p><sup>II</sup>Funda&#231;&#227;o de Medicina Tropical do Amazonas</p>
      <p><sup>III</sup>Universidade do Estado do Amazonas, Manaus, AM - Brasil</p>
      <p>Mailing address</p>
      <p>
        <bold>SUMMARY</bold>
      </p>
      <p>This study assessed the frequency of chronic chagasic cardiopathy (CCC) in 37 autochthonus patients from Amazon region with left ventricular systolic dysfunction of undefined etiology. Three cases were diagnosed in the studied sample, with an 8.1% frequency.</p>
      <p><bold>Key words:</bold> Frequency, chagas cardiomyopathy, Amazon region.</p>
      <p>
        <bold>Introduction</bold>
      </p>
      <p>The Amazon region has been considered a low-risk area for Chagas Disease (CD) for many years. Recently, the diagnosis of acute as much as chronic cases has been frequent in the region<sup>1</sup>. However, there are reports of only five chronic cases with dilated cardiomyopathy of chagasic etiology in autochthonus people from Amazon region<sup>2,3</sup>.</p>
      <p>There are no studies that evaluate the CD frequency in patients with dilated cardiomyopathy in Amazon region region. In other areas, CD responds for a significant portion of the cases. However, this etiology is rarely remembered among autochthonus patients from Amazon region, thus not being performed the serology for <italic>Trypanosoma cruzi</italic>, which may underestimate the disease diagnosis.</p>
      <p>The objective of this study was to assess the frequency of chronic chagasic cardiopathy (CCC) in autochthonus patients from Amazon region with dilated cardiomyopathy and left ventricular systolic dysfunction of undefined etiology.</p>
      <p>
        <bold>Methods</bold>
      </p>
      <p>Prospective and transversal study that assessed 37 patients submitted to transthoracic echocardiogram in the period between 2007 July and December at Francisca Mendes university hospital from Amazonas, Brazil.</p>
      <p>The Francisca Mendes hospital was chosen because it is the only high complexity reference center for cardiology registered in the Brazilian public health system (SUS, acronym in Portuguese) of Amazonas State. This service admits patients from the whole State of Amazonas and from other States of the occidental Amazon region.</p>
      <p>Patients from both genders, older than 12 years old and with ejection fraction <underline>&lt;</underline> 45% in transthoracic echocardiogram were included in the study, as all of them were autochthonus from Amazon region.</p>
      <p>All patients natural from Brazilian Amazonian region without having previously travelled to other regions were considered as autochthonus.</p>
      <p>Patients with evidence for coronariopathy, arterial hypertension, valvular heart disease or congenital cardiopathies were excluded from the study.</p>
      <p>The study was approved by the Ethics Committees of Universidade Federal do Amazonas and Funda&#231;&#227;o de Medicina Tropical do Amazonas. Patients signed the informed consent.</p>
      <p>Serology for CD was carried out with immunoglobulin G (IgG) research by Indirect Immunofluorescence and ELISA techniques at Funda&#231;&#227;o de Medicina Tropical do Amazonas.</p>
      <p>The Indirect Immunofluorescence was performed by means of a kit produced by Bio-Manguinhos (Funda&#231;&#227;o Oswaldo Cruz)<sup>4</sup> and the ELISA technique, with recombining antigen (Pathozyme Chagas<sup>&#174;</sup>)<sup>5</sup>.</p>
      <p>Patients with one or two reagent methods underwent Western-Blot (TESA-BLOT)<sup>6</sup>, and patients that presented two reagent methods were considered carriers of chagasic cardiopathy.</p>
      <p>
        <bold>Results</bold>
      </p>
      <p>During the study period, 2,039 transthoracic echocardiograms were carried out, and 196 patients presented ejection fraction of left ventricle (LV) <underline>&lt;</underline> 45%.</p>
      <p>After the assessment of inclusion and exclusion criteria, 37 patients were included in the study (mean age of 62.9 years old, 81% males). Mean ejection fraction of LV was 29.4%.</p>
      <p>Patients' naturalness was: 43.2% from the Amazonas countryside; 35.1% from Manaus municipality (AM); 13.5% from Par&#225;; 5.4% from Maranh&#227;o and 2.7% from Acre.</p>
      <p>The indirect immunofluorescence was reagent in eight cases (21.6%), ELISA in two cases (5.4%) and Western-Blot in three cases (8.1%).</p>
      <p>Three patients were diagnosed with CCC, with a frequency 8.1% in the whole studied sample.</p>
      <p>Data from positive CCC patients are described in <xref ref-type="table" rid="en_28t1-body2">Table 1</xref>.</p>
      <p content-type="asset">
        <table-wrap id="en_28t1-body2">
          <graphic xlink:href="1678-4170-abc-93-06-e107-00028-gt01-en.jpg"/></table-wrap>
      </p>
      <p>
        <bold>Discussion</bold>
      </p>
      <p>Amazon region is considered a hypoendemic area for CD. Acute cases have been occurring in an isolate way or in outbreaks, with approximately 440 reported cases in the region. With regard to chronic cases, seropositivity rate ranges from 1 to 3%, with higher risk in certain subregions<sup>1</sup>.</p>
      <p>One of these subregions is Barcelos municipality, placed at the Rio Negro microregion. In this area, transmission related to piassaba fibers extraction was reported. Three investigations carried out between 1991 and 1997 and comprising 2,254 individuals from Barcelos have showed a 2.8 to 5% prevalence of confirmed positive serology by means of recombining ELISA and Western Blot<sup>7,8</sup>.</p>
      <p>With regard to the etiologic agent, the <italic>T. cruzi</italic> from zimodem 1, zimodem 3 or hybrid Z1/Z3 groups has been described. These strains are different from those found in Brazilian endemic zones, where zimodem 2 is predominant<sup>1</sup>. The pathogenicity of Amazon region strains are not totally known; however, it is believed that they cause a low morbidity, probably lower than the morbidity found in endemic areas<sup>1,2</sup>.</p>
      <p>Despite that, two fatal cases of dilated cardiomyopathy and three cases that presented echocardiographic alterations typical of CD in patients with chronic chagasic infection reported in Barcelos<sup>2,3</sup>.</p>
      <p>The importance of CD as a cause for dilated cardiomyopathy in Amazon region is not completely understood yet. In endemic areas, the frequency is variable, but significant. The present study, with a frequency of 8.1% among patients without defined etiology, demonstrates that the chagasic cardiopathy is an important cause for heart failure in the Amazon region.</p>
      <p>The epidemiological history of two patients was compatible with CD. The first patient worked for three years with piassaba extraction in Barcelos municipality. The second patient lives in the Tarum&#227;-Mirim settlement, in Manaus, and worked for 12 years at a rubber plantation in Rio Purus (<xref ref-type="fig" rid="f1-body2">Figure 1</xref>). In these three localizations, the presence of infected vectors, sylvan reservoirs and human infection cases was reported<sup>7-10</sup>. The third patient was from Iranduba, where there is no register of studies related to CD. It is important to emphasize that the three mentioned patients were from municipalities of the Amazonas countryside.</p>
      <fig id="f1-body2">
        <graphic xlink:href="1678-4170-abc-93-06-e107-00028-gf01-en.jpg"/></fig>
      <p>
        <bold>Conclusion</bold>
      </p>
      <p>The present study suggests that CD is a significant etiology of dilated cardiomyopathy in the Amazon region, and its investigation in autochthonus patients is important. However, studies with bigger samples are necessary, as to know better the importance of CD as etiology of cardiopathies in Amazon region.</p>
      <p>
        <bold>Acknowledgments</bold>
      </p>
      <p>The authors thank to Dr. Eufrozina Setsu Umezawa and Norival Kesper Junior, from Instituto de Medicina Tropical of S&#227;o Paulo, for the Western-Blot accomplishment, and to Dr. F&#225;bio Fernandes, from Instituto do Cora&#231;&#227;o of Universidade de S&#227;o Paulo, for reading the article and offering suggestions.</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">Cardiopat&#237;a chag&#225;sica cr&#243;nica en la Amazon&#237;a: una etiolog&#237;a que recordar</article-title>
      </title-group>
      <abstract xml:lang="es">
        <p>Este estudio evalu&#243; la frecuencia de cardiopat&#237;a chag&#225;sica cr&#243;nica (CCC) en 37 pacientes aut&#243;ctonos de la Amazon&#237;a con disfunci&#243;n sist&#243;lica ventricular izquierda sin etiolog&#237;a definida. Se diagnosticaron tres casos con frecuencia del 8,1% en el grupo estudiado.</p>
      </abstract>
      <kwd-group xml:lang="es">
        <kwd>Frecuencia</kwd>
        <kwd>cardiopat&#237;a chag&#225;sica</kwd>
        <kwd>Amazon&#237;a</kwd>
      </kwd-group>
    </front-stub>
    <body>
      <p>
        <bold>COMUNICACI&#211;N BREVE</bold>
      </p>
      <p>
        <fn id="top-body3">
          <label>
            <bold>Cardiopat&#237;a chag&#225;sica cr&#243;nica en la amazon&#237;a: una etiolog&#237;a que recordar</bold>
          </label>
          <p>
            <bold>Jo&#227;o Marcos Bemfica Barbosa Ferreira<sup>I</sup>; Jorge Augusto de Oliveira Guerra<sup>II, III</sup>; Belisa Maria Lopes Magalh&#227;es<sup>III</sup>; Le&#237;la I. A. R. C. Coelho<sup>II</sup>; Marcel Gon&#231;alves Maciel<sup>III</sup>; Maria das Gra&#231;as Vale Barbosa<sup>II, III</sup></bold>
          </p>
        </fn>
      </p>
      <p><sup>I</sup>Hospital Universitario Francisca Mendes (UFAM), Manaus, AM - Brasil</p>
      <p><sup>II</sup>Fundaci&#243;n de Medicina Tropical do Amazonas, Manaus, AM - Brasil </p>
      <p><sup>III</sup>Universidad del Estado de Amazonas, Manaus, AM - Brasil</p>
      <p>Correspondencia</p>
      <p>
        <bold>RESUMEN</bold>
      </p>
      <p>Este estudio evalu&#243; la frecuencia de cardiopat&#237;a chag&#225;sica cr&#243;nica (CCC) en 37 pacientes aut&#243;ctonos de la Amazon&#237;a con disfunci&#243;n sist&#243;lica ventricular izquierda sin etiolog&#237;a definida. Se diagnosticaron tres casos con frecuencia del 8,1% en el grupo estudiado.</p>
      <p><bold>Palabras clave: </bold> Frecuencia; cardiopat&#237;a chag&#225;sica; Amazon&#237;a</p>
      <p>
        <bold>Introducci&#243;n</bold>
      </p>
      <p>La Amazon&#237;a se consider&#243; por muchos a&#241;os como un &#225;rea de bajo riesgo para la enfermedad de Chagas (EC). Recientemente, viene siendo m&#225;s frecuente el diagn&#243;stico tanto de casos agudos como de cr&#243;nicos en la regi&#243;n<sup>1</sup>. Hay, sin embargo, relatos de solamente cinco casos cr&#243;nicos con miocardiopat&#237;a dilatada de etiolog&#237;a chag&#225;sica en aut&#243;ctonos de la Amazon&#237;a<sup>2,3</sup>.</p>
      <p>No existen estudios que eval&#250;en la frecuencia de EC en pacientes con miocardiopat&#237;a dilatada en la Amazon&#237;a. En otras &#225;reas, la EC responde por una parcela significativa de los casos. No obstante, esta etiolog&#237;a se nota raramente en pacientes aut&#243;ctonos de la Amazon&#237;a, no realiz&#225;ndose la serolog&#237;a para <italic>Trypanosoma cruzi,</italic> lo que puede subestimar el diagn&#243;stico de la enfermedad.</p>
      <p>El objetivo de este estudio fue evaluar la frecuencia de cardiopat&#237;a chag&#225;sica cr&#243;nica (CCC) en pacientes aut&#243;ctonos de la Amazon&#237;a con miocardiopat&#237;a y disfunci&#243;n sist&#243;lica ventricular izquierda sin etiolog&#237;a definida.</p>
      <p>
        <bold>M&#233;todos</bold>
      </p>
      <p>Estudio prospectivo y transversal con evaluaci&#243;n de 37 pacientes que realizaron ecocardiograma transtor&#225;cico entre julio y diciembre de 2007, en el Hospital Universitario Francisca Mendes de la Universidad Federal de Amazonas.</p>
      <p>Se eligi&#243; el Hospital Universitario Francisca Mendes por tratarse del &#250;nico Centro de Referencia de Alta Complejidad en Cardiolog&#237;a acreditado por el Sistema &#218;nico de Salud (SUS) en el estado de Amazonas. Este servicio atiende a pacientes de todo el estado de Amazonas y de otros estados de la Amazon&#237;a Occidental.</p>
      <p>Se incluyeron a pacientes de ambos sexos, con edad superior a 12 a&#241;os y fracci&#243;n de eyecci&#243;n <underline>&lt;</underline> 45% en el ecocardiograma transtor&#225;cico, y todos eran aut&#243;ctonos de la Amazon&#237;a.</p>
      <p>Se consideraron como aut&#243;ctonos a aqu&#233;llos nativos de la Amazon&#237;a Brasile&#241;a, sin cualquier viaje previo para otras regiones.</p>
      <p>Se excluyeron a aqu&#233;llos con evidencias de coronariopat&#237;a, hipertensi&#243;n arterial, valvulopat&#237;as o cardiopat&#237;as cong&#233;nitas.</p>
      <p>Los Comit&#233;s de &#201;tica en Investigaci&#243;n de la Universidad Federal de Amazonas y de Fundaci&#243;n de Medicina Tropical de Amazonas aprobaron el estudio. Todos los pacientes firmaron el formulario de consentimiento informado.</p>
      <p>Se llev&#243; a cabo la serolog&#237;a para EC con investigaci&#243;n de IgG mediante los m&#233;todos de Inmunofluorescencia Indirecta y ELISA en la Fundaci&#243;n de Medicina Tropical de Amazonas</p>
      <p>La Inmunofluorescencia Indirecta se efectu&#243; con <italic>kit de Biomanguinhos</italic> (Funda&#231;&#227;o Oswaldo Cruz)<sup>4</sup> y el m&#233;todo ELISA, con ant&#237;geno recombinante (Pathozyme Chagas<sup>&#174;</sup>)<sup>5</sup>.</p>
      <p>Los pacientes con uno o dos m&#233;todos reactivos realizaron Western-Blot (TESA-BLOT)<sup>6</sup>.</p>
      <p>Se consideraron con cardiopat&#237;a chag&#225;sica reactivos aqu&#233;llos con dos m&#233;todos cr&#243;nica.</p>
      <p>
        <bold>Resultados</bold>
      </p>
      <p>En el per&#237;odo del estudio, se llevaron a cabo 2.039 ex&#225;menes de ecocardiograma transtor&#225;cico, con 196 pacientes presentando fracci&#243;n de eyecci&#243;n de VI <underline>&lt;</underline> 45%.</p>
      <p>Tras evaluaci&#243;n de los criterios de inclusi&#243;n y exclusi&#243;n, 37 pacientes se incluyeron en el estudio (promedio de edad de 62,9 a&#241;os, el 81% del sexo masculino). El promedio de la fracci&#243;n de eyecci&#243;n del VI fue del 29,4%.</p>
      <p>La naturalidad de los pacientes fue del 43,2% del interior del estado de Amazonas; el 35,1% del municipio de Manaus (AM); el 13,5 % del Par&#225;; el 5,4% del Maranh&#227;o y el 2,7% del Acre.</p>
      <p>La inmunofluorescencia indirecta fue reactiva en ocho casos (21,6%), el ELISA en dos (5,4%) y el Western-Blot en tres (8,1%).</p>
      <p>Tres pacientes recibieron el diagn&#243;stico de CCC. La frecuencia de CCC en la poblaci&#243;n estudiada fue del 8,1%.</p>
      <p>Los de datos de los pacientes positivos est&#225;n descriptos en el <xref ref-type="table" rid="es_28t1-body3">Tabla 1</xref>.</p>
      <p content-type="asset">
        <table-wrap id="es_28t1-body3">
          <graphic xlink:href="1678-4170-abc-93-06-e107-00028-gt01-es.jpg"/></table-wrap>
      </p>
      <p>
        <bold>Discusi&#243;n</bold>
      </p>
      <p>Se considera la Amazon&#237;a como hipoend&#233;mica para la EC. Recientemente han ocurrido casos agudos en surtos o aislados, con relatos de aproximadamente 440 casos en la regi&#243;n. Respecto a los casos cr&#243;nicos, el riesgo de seropositividad el del 1% al 3%, con tasa mayor en ciertas subregiones<sup>1</sup>.</p>
      <p>Una de estas subregiones es el municipio de Barcelos, en la microregi&#243;n del R&#237;o Negro (AM). En este local se describi&#243; la transmisi&#243;n relacionada a la extracci&#243;n de fibras de piasava. Tres averiguaciones que se hicieron entre el 1991 y el 1997, involucrando a 2.254 individuos de Barcelos, revelaron prevalencia del 2,8% al 5% de serolog&#237;as positivas confirmadas con ELISA recombinante y Western Blot<sup>7,8</sup>.</p>
      <p>Respecto al agente etiol&#243;gico, se viene describiendo en la Amazon&#237;a el <italic>T. cruzi</italic> de los grupos zimodema 1, zimodema 3 o h&#237;brido Z1/Z3. Estas cepas son diferentes de las encontradas en las zonas end&#233;micas de Brasil donde predomina el zimodema 2<sup>1</sup>. No se conoce totalmente la patogenicidad de las cepas de la Amazon&#237;a. Sin embargo, se cree que ocasionen baja morbilidad, probablemente menor que la encontrada en las &#225;reas end&#233;micas<sup>1,2</sup>.</p>
      <p>Pese a ello, se describieron dos casos fatales de miocardiopat&#237;a dilatada y tres casos con alteraciones ecocardiogr&#225;ficas t&#237;picas de EC en pacientes con infecci&#243;n chag&#225;sica cr&#243;nica en Barcelos (AM)<sup>2,3</sup>.</p>
      <p>Todav&#237;a no conocemos totalmente la importancia de la EC como causa de miocardiopat&#237;a dilatada en la Amazon&#237;a. En &#225;reas end&#233;micas, la frecuencia es variable, no obstante significante. El presente estudio con frecuencia del 8,1% en pacientes sin etiolog&#237;a definida evidencia que la cardiopat&#237;a chag&#225;sica es una causa importante de insuficiencia cardiaca en la regi&#243;n amaz&#243;nica.</p>
      <p>La historia epidemiol&#243;gica de dos pacientes es compatible con EC. El primer paciente trabaj&#243; 3 a&#241;os con extracci&#243;n de piasava en el municipio de Barcelos (AM). El segundo paciente vive actualmente en el asentamiento Tarum&#227;-Mirim en Manaus (AM) y trabaj&#243; 12 a&#241;os en un seringal en el R&#237;o Purus (AM) (<xref ref-type="fig" rid="es_28f1-body3">Figura 1</xref>). En estos tres locales se relat&#243; la presencia de vectores infectados, de reservorios silvestres y de casos de infecci&#243;n humana<sup>7-10</sup>. El tercer paciente proviene de Iranduba (AM) donde no existen estudios relacionados a EC. Es importante destacar que estos tres pacientes eran de municipios del interior de Amazonas.</p>
      <p content-type="asset">
        <fig id="es_28f1-body3">
          <graphic xlink:href="1678-4170-abc-93-06-e107-00028-gf01-es.jpg"/></fig>
      </p>
      <p>
        <bold>Conclusi&#243;n</bold>
      </p>
      <p>El presente estudio sugiere que la EC es una etiolog&#237;a significativa de miocardiopat&#237;a dilatada en la regi&#243;n amaz&#243;nica, y es importante su investigaci&#243;n en los pacientes aut&#243;ctonos. Sin embargo son necesarios estudios con mayor casu&#237;stica para conocerse mejor la importancia de la EC como etiolog&#237;a de las cardiopat&#237;as en la Amazon&#237;a.</p>
      <p>
        <bold>Agradecimientos</bold>
      </p>
      <p>Les agradecemos a Dra. Eufrozina Setsu Umezawa y al Norival Kesper J&#250;nior del Instituto de Medicina Tropical de S&#227;o Paulo, por la realizaci&#243;n del Western-Blot. Le agradecemos tambi&#233;n al Dr. F&#225;bio Fernandes, del Instituto do Cora&#231;&#227;o, de la Universidad de S&#227;o Paulo, por la lectura del art&#237;culo y las sugerencias realizadas.</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 tuvo 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>
