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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">tZmMwt5ksfKHVkJyLHsLc8k</article-id>
      <article-id pub-id-type="other">00024</article-id>
      <article-id pub-id-type="publisher-id" specific-use="scielo-v2">S0066-782X2006001700024</article-id>
      <article-id pub-id-type="publisher-id" specific-use="scielo-v1">S0066-782X(06)08700424</article-id>
      <article-id pub-id-type="doi">10.1590/S0066-782X2006001700024</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Relato de Caso</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Marcapasso bi-atrial epic&#225;rdico subxif&#243;ide na obstru&#231;&#227;o da veia cava superior</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Costa</surname>
            <given-names>Roberto</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Le&#227;o</surname>
            <given-names>Maria In&#234;s de Paula</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Silva</surname>
            <given-names>K&#225;tia Regina da</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Camargo</surname>
            <given-names>Paulo Roberto</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Costa</surname>
            <given-names>Regina Val&#233;ria</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
      </contrib-group>
      <aff id="aff01">
        <addr-line>
          <named-content content-type="city">S&#227;o Paulo</named-content>
          <named-content content-type="state">S&#227;o Paulo</named-content>
        </addr-line>
        <institution content-type="orgname">Universidade de S&#227;o Paulo</institution>
        <institution content-type="orgdiv1">FM </institution>
        <institution content-type="orgdiv2">Hospital das Cl&#237;nicas</institution>
        <country country="BR">Brazil</country>
      </aff>
      <pub-date date-type="collection" publication-format="electronic">
        <month>10</month>
        <year>2006</year>
      </pub-date>
      <volume>87</volume>
      <issue>4</issue>
      <fpage>e101</fpage>
      <lpage>e103</lpage>
      <history>
        <date date-type="accepted">
          <day>01</day>
          <month>06</month>
          <year>2006</year>
        </date>
        <date date-type="received">
          <day>12</day>
          <month>05</month>
          <year>2006</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>Um paciente portador de marcapasso definitivo bi-atrial-ventricular por fibrila&#231;&#227;o atrial parox&#237;stica e bradicardia sinusal, em uso cr&#244;nico de anticoagulante oral, apresentou sinais cl&#237;nicos da s&#237;ndrome da veia cava superior. A venografia por subtra&#231;&#227;o digital mostrou obstru&#231;&#227;o total do tronco braquiocef&#225;lico venoso direito e grande dificuldade de fluxo sang&#252;&#237;neo da veia inominada para a veia cava superior. A abordagem terap&#234;utica constou da remo&#231;&#227;o completa do sistema transvenoso seguida de reimplante do sistema bi-atrial-ventricular por t&#233;cnica epimioc&#225;rdica pela via subxif&#243;ide assistida por fluoroscopia.</p>
      </abstract>
      <kwd-group xml:lang="pt" kwd-group-type="author-generated">
        <kwd>Marcapasso artificial</kwd>
        <kwd>marcapassso bi-atrial</kwd>
        <kwd>s&#237;ndrome da veia cava superior</kwd>
        <kwd>fibrila&#231;&#227;o atrial</kwd>
      </kwd-group>
      <pub-date publication-format="electronic" date-type="pub">
        <day>21</day>
        <month>11</month>
        <year>2006</year>
      </pub-date>
    </article-meta>
  </front>
  <body>
    <p>
      <bold>RELATO DE CASO</bold>
    </p>
    <p>
      <bold>Marcapasso bi-atrial epic&#225;rdico subxif&#243;ide na obstru&#231;&#227;o da veia cava superior</bold>
    </p>
    <p>
      <bold>Roberto Costa; Maria In&#234;s de Paula Le&#227;o; K&#225;tia Regina da Silva; Paulo Roberto Camargo; Regina Val&#233;ria Costa</bold>
    </p>
    <p>Instituto do Cora&#231;&#227;o do Hospital das Cl&#237;nicas - FMUSP - S&#227;o Paulo, SP</p>
    <p>
      <xref ref-type="corresp" rid="back">Correspond&#234;ncia</xref>
    </p>
    <p>
      <bold>RESUMO</bold>
    </p>
    <p>Um paciente portador de marcapasso definitivo bi-atrial-ventricular por fibrila&#231;&#227;o atrial parox&#237;stica e bradicardia sinusal, em uso cr&#244;nico de anticoagulante oral, apresentou sinais cl&#237;nicos da s&#237;ndrome da veia cava superior. A venografia por subtra&#231;&#227;o digital mostrou obstru&#231;&#227;o total do tronco braquiocef&#225;lico venoso direito e grande dificuldade de fluxo sang&#252;&#237;neo da veia inominada para a veia cava superior. A abordagem terap&#234;utica constou da remo&#231;&#227;o completa do sistema transvenoso seguida de reimplante do sistema bi-atrial-ventricular por t&#233;cnica epimioc&#225;rdica pela via subxif&#243;ide assistida por fluoroscopia.</p>
    <p><bold>Palavras-chave:</bold> Marcapasso artificial, marcapassso bi-atrial, s&#237;ndrome da veia cava superior, fibrila&#231;&#227;o atrial.</p>
    <p>A s&#237;ndrome da veia cava superior p&#243;s-implante de marcapasso transvenoso &#233; complica&#231;&#227;o rara. Sua abordagem terap&#234;utica tem sido realizada pela anticoagula&#231;&#227;o associada ou n&#227;o a tromb&#243;lise, venoplastia percut&#226;nea ou abordagem cir&#250;rgica a c&#233;u aberto<sup>1-5</sup>.</p>
    <p>A estimula&#231;&#227;o multiss&#237;tio atrial definitiva tem apresentado resultados consistentes na preven&#231;&#227;o da fibrila&#231;&#227;o atrial em pacientes com doen&#231;a do n&#243; sinusal, diminuindo o n&#250;mero de recidivas e retardando a instala&#231;&#227;o da fibrila&#231;&#227;o atrial permanente<sup>6-9</sup>.</p>
    <p>O objetivo do presente relato &#233; descrever o caso de um paciente portador de doen&#231;a do n&#243; sinusal e fibrila&#231;&#227;o atrial persistente, que evoluiu com s&#237;ndrome da veia cava superior cinco anos ap&#243;s o implante de marcapasso bi-atrial-ventricular, cujo tratamento implicou na extra&#231;&#227;o completa do sistema transvenoso e seu reimplante pela via epimioc&#225;rdica subxif&#243;ide.</p>
    <p>
      <bold>Relato do Caso</bold>
    </p>
    <p>Homem de 66 anos, portador de fibrila&#231;&#227;o e fl&#252;tter atriais refrat&#225;rios &#224; terapia farmacol&#243;gica, havia sido submetido a duas tentativas de abla&#231;&#227;o por cateter. J&#225; havia apresentado acidente vascular cerebral isqu&#234;mico com dist&#250;rbios visuais transit&#243;rios e estava em uso cr&#244;nico de varfarina e amiodarona.</p>
    <p>Em mar&#231;o de 2001, apresentou s&#237;ncope associada a bradicardia sinusal persistente, sendo submetido a implante de marcapasso bi-atrial-ventricular transvenoso permanente. Os cabos-eletrodos <italic>Medtronic</italic> 4068, para aur&#237;cula e ventr&#237;culo direitos, e 2188, para seio coron&#225;rio distal, foram implantados por dissec&#231;&#227;o da veia cef&#225;lica e pun&#231;&#227;o da veia subcl&#225;via direitas com alojamento do gerador de pulsos em regi&#227;o subpeitoral. O uso de varfarina foi mantido, sendo a amiodarona substitu&#237;da por sotalol devido a hipotireoidismo. Manteve-se assintom&#225;tico por cinco anos, em ritmo de marcapasso, com detec&#231;&#227;o eventual de epis&#243;dios de fibrila&#231;&#227;o atrial nos contadores diagn&#243;sticos do gerador de pulsos.</p>
    <p>Em mar&#231;o de 2005, tr&#234;s meses ap&#243;s a troca eletiva de gerador de pulsos, apresentou edema e rubor em face, pesco&#231;o e membro superior direito. A avalia&#231;&#227;o, pela ultra-sonografia e pela tomografia do t&#243;rax, sugeriu obstru&#231;&#227;o da veia cava superior. A venografia por subtra&#231;&#227;o digital, com inje&#231;&#227;o bilateral de contraste, revelou trombose do tronco braquiocef&#225;lico venoso direito com circula&#231;&#227;o colateral e estenose grave da jun&#231;&#227;o da veia inominada com a veia cava superior (<xref ref-type="fig" rid="f1">fig. 1</xref>).</p>
    <p content-type="asset">
      <fig id="f1">
        <graphic xlink:href="1678-4170-abc-87-04-e101-00024-gf01.jpg"/></fig>
    </p>
    <p>O tratamento estabelecido foi a remo&#231;&#227;o completa do sistema transvenoso e reimplante epic&#225;rdico. Sob anestesia geral, realizou-se: remo&#231;&#227;o do gerador de pulsos; extra&#231;&#227;o dos cabos atrial direito e ventricular, por contra-tra&#231;&#227;o, e retirada do cabo atrial esquerdo, por tra&#231;&#227;o simples. O reimplante foi feito por incis&#227;o longitudinal de aproximadamente cinco cent&#237;metros sobre o ap&#234;ndice xif&#243;ide com pericardiotomia em forma de "T" invertido. O cabo-eletrodo epimioc&#225;rdico <italic>Medtronic</italic> 4968 foi implantado na parede diafragm&#225;tica do ventr&#237;culo direito. Pela mesma abertura, com o aux&#237;lio de fluoroscopia, o cabo-eletrodo <italic>Medtronic</italic> 5038 (A-V "<italic>single lead</italic>") foi conduzido, pelo espa&#231;o peric&#225;rdico, para a regi&#227;o p&#243;stero-lateral do ventr&#237;culo esquerdo at&#233; atingir, pelo seio transverso, o topo do &#225;trio direito. A ponta do cabo-eletrodo foi implantada no epic&#225;rdio atrial, entre a veia cava superior e a aorta ascendente. Os p&#243;los "flutuantes" do cabo-eletrodo 5038 ficaram localizados junto &#224; aur&#237;cula esquerda e foram utilizados para estimula&#231;&#227;o atrial esquerda. As medidas, obtidas com Analisador <italic>Medtronic</italic> 2090, foram adequadas para estimula&#231;&#227;o e sensibilidade, n&#227;o sendo observada estimula&#231;&#227;o fr&#234;nica. O gerador de pulsos, <italic>Biotronik Stratos LA</italic>, foi reimplantado no hipoc&#244;ndrio esquerdo em posi&#231;&#227;o submuscular (<xref ref-type="fig" rid="f2">fig. 2</xref>).</p>
    <p content-type="asset">
      <fig id="f2">
        <graphic xlink:href="1678-4170-abc-87-04-e101-00024-gf02.jpg"/></fig>
    </p>
    <p>Houve regress&#227;o completa dos sinais de obstru&#231;&#227;o da veia cava no p&#243;s-operat&#243;rio imediato, mantendo-se assim at&#233; a &#250;ltima avalia&#231;&#227;o. O paciente foi mantido em uso de varfarina e persiste em ritmo de marcapasso atrial com boa captura atrial e ventricular, dois meses ap&#243;s o procedimento.</p>
    <p>
      <bold>Discuss&#227;o</bold>
    </p>
    <p>O tratamento da s&#237;ndrome da veia cava superior p&#243;s-implante de cabos-eletrodos transvenosos, por sua raridade, ainda n&#227;o est&#225; padronizado. T&#234;m sido utilizadas a anticoagula&#231;&#227;o, a tromb&#243;lise e a desobstru&#231;&#227;o mec&#226;nica, com ou sem a retirada do sistema de estimula&#231;&#227;o. No presente caso, em fun&#231;&#227;o do fluxo lento da veia inominada para a veia cava superior, optou-se pela remo&#231;&#227;o do sistema transvenoso. Os riscos inerentes ao uso de trombol&#237;ticos e os maus resultados em longo prazo da venoplastia pesaram nessa decis&#227;o<sup>1-5</sup>.</p>
    <p>A estimula&#231;&#227;o multiss&#237;tio atrial permitiu a manuten&#231;&#227;o do ritmo do paciente por cinco anos, com poucos epis&#243;dios de fibrila&#231;&#227;o atrial parox&#237;stica autolimitados e por isso foi mantida no reimplante. A estimula&#231;&#227;o ventricular tamb&#233;m foi indicada, caso no futuro houvesse necessidade de abla&#231;&#227;o da jun&#231;&#227;o atrioventricular.</p>
    <p>As op&#231;&#245;es para implante de marcapasso endoc&#225;rdico na obstru&#231;&#227;o da veia cava superior t&#234;m sido a veia femoral e a toracotomia direita atrav&#233;s da parede atrial<sup>1,4</sup>. Pela gravidade do quadro tromboemb&#243;lico, mesmo na vig&#234;ncia de anticoagula&#231;&#227;o oral, optou-se por n&#227;o utilizar a via endoc&#225;rdica no reimplante. Com base na t&#233;cnica de mapeamento e abla&#231;&#227;o epic&#225;rdica, descrita por Sosa e Scanavacca<sup>10</sup>, e com a finalidade de evitar a toracotomia transesternal para abordagem simult&#226;nea dos &#225;trios direito e esquerdo, utilizamos o presente acesso. O uso do cateter, originalmente desenvolvido para estimula&#231;&#227;o atrioventricular com cabo &#250;nico, guiado pela fluoroscopia, permitiu a estimula&#231;&#227;o atrial esquerda e direita com um s&#243; cabo. A passagem pelo seio transverso estabilizou a posi&#231;&#227;o do cabo-eletrodo.</p>
    <p>O seguimento de m&#233;dio prazo mostrou a viabilidade desse tipo de abordagem para o implante bi-atrial. O baixo risco desse procedimento, associado &#224; m&#237;nima invas&#227;o, pode torn&#225;-lo uma boa alternativa para a estimula&#231;&#227;o multiss&#237;tio, caso a reprodutibilidade, seguran&#231;a e efic&#225;cia dessa t&#233;cnica sejam comprovadas.</p>
    <p>
      <bold>Potencial Conflito de Interesses</bold>
    </p>
    <p>Declaro n&#227;o haver conflitos de interesses pertinentes.</p>
    <p>
      <fn id="back" fn-type="corresp">
        <label>
          <bold>Correspond&#234;ncia:</bold>
        </label>
        <p> Roberto Costa </p>
        <p> R. Lisboa, 518/131 &#150; Cerqueira C&#233;sar </p>
        <p> 05413-000 &#150; S&#227;o Paulo, SP </p>
        <p> E-mail: </p>
        <p>
          <email xlink:href="rcosta@cardiol.br">rcosta@cardiol.br</email>
        </p>
      </fn>
    </p>
    <p>Recebido em 12/05/06 </p>
    <p> Aceito em 01/06/06</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">Bi-atrial subxiphoid epicardial pacemaker in superior vena cava syndrome</article-title>
      </title-group>
      <abstract xml:lang="en">
        <p>A patient with a bi-atrial-ventricular permanent pacemaker due to paroxystic atrial fibrillation associated to sinus bradycardia, in chronic use of oral anticoagulant, presented clinical signs of superior vena cava syndrome. Digital subtraction venography showed total obstruction of the right brachiocephalic venous trunk and severe stenosis of the connection of the left trunk to the superior vena cava. The therapeutic approach consisted of complete removal of transvenous system followed by re-implant of the bi-atrial-ventricular system using an epicardial subxiphoid access with fluoroscopic assistance</p>
      </abstract>
      <kwd-group xml:lang="en">
        <kwd>Pacemaker artificial</kwd>
        <kwd>bi-atrial pacemaker</kwd>
        <kwd>superior vena cava syndrome</kwd>
        <kwd>atrial fibrillation</kwd>
      </kwd-group>
    </front-stub>
    <body>
      <p>
        <bold>CASE REPORT</bold>
      </p>
      <p>
        <bold>Bi-atrial subxiphoid epicardial pacemaker in superior vena cava syndrome</bold>
      </p>
      <p>
        <bold>Roberto Costa; Maria In&#234;s de Paula Le&#227;o; K&#225;tia Regina da Silva; Paulo Roberto Camargo; Regina Val&#233;ria Costa</bold>
      </p>
      <p>Heart Institute of the Hospital das Cl&#237;nicas of the University of S&#227;o Paulo Medical School - S&#227;o Paulo, SP - Brazil</p>
      <p>
        <xref ref-type="corresp" rid="back-body2">Mailing Address</xref>
      </p>
      <p>
        <bold>ABSTRACT</bold>
      </p>
      <p>A patient with a bi-atrial-ventricular permanent pacemaker due to paroxystic atrial fibrillation associated to sinus bradycardia, in chronic use of oral anticoagulant, presented clinical signs of superior vena cava syndrome. Digital subtraction venography showed total obstruction of the right brachiocephalic venous trunk and severe stenosis of the connection of the left trunk to the superior vena cava. The therapeutic approach consisted of complete removal of transvenous system followed by re-implant of the bi-atrial-ventricular system using an epicardial subxiphoid access with fluoroscopic assistance.</p>
      <p><bold>Key words:</bold> Pacemaker artificial, bi-atrial pacemaker, superior vena cava syndrome, atrial fibrillation.</p>
      <p>The superior vena cava syndrome following transvenous pacemaker implantation is an uncommon complication. The therapeutic approach for the condition has been anticoagulation with or without thrombolysis, percutaneous venoplasty, or open-heart surgery.</p>
      <p>The permanent multi-site atrial stimulation approach has shown consistent results in preventing atrial fibrillation in patients with sinus node disease, reducing the number of recidivating cases, and delaying the onset of permanent atrial fibrillation<sup>6-9</sup>.</p>
      <p>The objective of this report is to describe the case of a patient with sinus node disease and persistent atrial fibrillation that progressed to superior vena cava syndrome five years after bi-atrial-ventricular pacemaker implantation. Treatment included the complete removal of the transvenous system and its re-implantation by epimyocardial subxiphoid access.</p>
      <p>
        <bold>Case Report</bold>
      </p>
      <p>A 66-year-old male patient with fibrillation and drug-refractory atrial flutters who had undergone two previous attempts of catheter ablation. The patient had already suffered a previous ischemic cerebrovascular accident with transient visual disorders and was under treatment with warfarin and amiodarone.</p>
      <p>In March 2001, he suffered a syncope associated with persistent sinus bradycardia, and had a permanent transvenous bi-atrial-ventricular pacemaker implanted. A <italic>Medtronic</italic> 4068 model electrode-cable for the right auricle and ventricle, and a 2188 model for the distal coronary sinus, were implanted by dissection of the cephalic vein and puncture of the right subclavian vein; the pulse generator was positioned in the subpectoral region. Warfarin administration was maintained, and amiodarone was replaced by sotalol due to hypothyroidism. The patient remained asymptomatic for five years, with a pacing rhythm and occasional episodes of atrial fibrillation detected by the diagnostic pulse generator counters.</p>
      <p>In March 2005, three months after an elective replacement of the pulse generator, the patient developed edema and rubor in his face, neck, and right upper limb. Ultrasound and chest X-ray evaluation suggested obstruction of the superior vena cava. Digital subtraction venography with bilateral injection of contrast material showed thrombosis of the right brachiocephalic venous trunk with collateral circulation, and severe stenosis at the innominate vein-superior vena cava junction (<xref ref-type="fig" rid="e24f1-body2">Fig. 1</xref>).</p>
      <p content-type="asset">
        <fig id="e24f1-body2">
          <graphic xlink:href="1678-4170-abc-87-04-e101-00024-gf01-en.jpg"/></fig>
      </p>
      <p>The therapeutic approach adopted was the complete removal of the transvenous system followed by epimyocardial re-implantation. With the patient under general anesthesia, the following was performed: removal of the pulse generator, removal of the right atrial and ventricular cables by counter-traction, and removal of the left atrial cable by simple traction. Re-implantation was performed by a longitudinal incision, approximately 5 cm long, over the xiphoid appendage, and an inverted T-shape pericardiotomy. The <italic>Medtronic</italic> 4968 epimyocardial electrode-cable was implanted in the diaphragmatic wall of the right ventricle. With the aid of fluoroscopy, the Medtronic 5038 (A-V "<italic>single lead</italic>") electrode-cable was inserted through the same opening and passed through the pericardial space to the post-lateral region of the left ventricle until it reached, via the transversal sinus, the apex of the right atrium. The tip of the cable-electrode was positioned on the atrial epicardium, between the superior vena cava and the ascending aorta. The "fluctuating" poles of the 5038 electrode-cable were positioned in the left auricle, and were used for left atrial stimulation. The values obtained with the <italic>Medtronic</italic> 2090 analyzer were adequate for stimulation and sensitivity. No phrenic stimulation was observed. The <italic>Biotronik Stratos LA</italic> pulse generator was re-implanted in the submuscular region of the left hypochondrium (<xref ref-type="fig" rid="e24f2-body2">Fig. 2</xref>).</p>
      <p content-type="asset">
        <fig id="e24f2-body2">
          <graphic xlink:href="1678-4170-abc-87-04-e101-00024-gf02-en.jpg"/></fig>
      </p>
      <p>Total regression of vena cava obstruction signs was obtained after the immediate postoperative period and persisted through the last evaluation. Patient continues to receive warfarin and remains in atrial pacing with good atrial-ventricular pacemaker capture two months after the procedure.</p>
      <p>
        <bold>Discussion</bold>
      </p>
      <p>Since it is so infrequent, the treatment of superior vena cava syndrome following transvenous electrode-cable implantation has not yet been standardized. Anticoagulation, thrombolysis, and mechanical unclogging, with or without the removal of the stimulation system, have been employed. In this case, due to the sluggish flow from the innominate vein to the superior vena cava, it was decided to remove the transvenous system. The risks associated with the use of thrombolytic agents and the poor long-term results of venoplasty were important factors taken into consideration.</p>
      <p>The multi-site atrial stimulation allowed maintenance of the patient's own rhythm for five years, with few episodes of self-limited atrial paroxysmal fibrillation, and therefore was preserved. Ventricular stimulation was also indicated, in case ablation at the atrial-ventricular junction is needed in the future.</p>
      <p>The femoral vein and right thoracotomy through the atrial wall have been the preferred options for endocardial pacemaker implantation.Due to the severity of the thromboembolic condition even during oral anticoagulation, it was decided not to use the endocardial pathway for the re-implantation procedure. Based on the epicardial mapping and ablation approach described by Sosa e Scanavacca<sup>10</sup>, and in an effort to avoid the trans-sternal thoracotomy to reach the right and left atria simultaneously, we decided to employ this access. The single-cable fluoroscopy-guided catheter, originally designed for atrioventricular stimulation, allowed performing left and right atrial stimulation with just one cable. The passage through the transversal sinus stabilized the position of the cable-electrode.</p>
      <p>Mid-term follow-up showed the viability of this kind of approach for the bi-atrial implantation. The low risk of this minimally invasive procedure may help it become a good alternative for multi-site stimulation, provided reproducibility, safety, and accuracy of the technique are confirmed.</p>
      <p>
        <bold>Potential Conflict of Interest</bold>
      </p>
      <p>No potential conflict of interest relevant to this article was reported.</p>
      <p>
        <bold>References</bold>
      </p>
      <p>
        <fn id="back-body2" fn-type="corresp">
          <label>
            <bold>Mailing Address:</bold>
          </label>
          <p> Roberto Costa</p>
          <p> R. Lisboa, 518/131 &#150; Cerqueira C&#233;sar</p>
          <p> 05413-000 &#150; S&#227;o Paulo, SP, Brazil</p>
          <p> E-mail: </p>
          <p>
            <email xlink:href="rcosta@cardiol.br">rcosta@cardiol.br</email>
          </p>
        </fn>
      </p>
      <p>Received on 05/12/06</p>
      <p> Accepted on 06/01/06</p>
    </body>
  </sub-article>
</article>
