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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">hTCQXYTqDnVCCKFCKR4Ndtb</article-id>
      <article-id pub-id-type="other">00001</article-id>
      <article-id pub-id-type="publisher-id" specific-use="scielo-v2">S0066-782X2011000500001</article-id>
      <article-id pub-id-type="publisher-id" specific-use="scielo-v1">S0066-782X(11)09600501</article-id>
      <article-id pub-id-type="doi">10.1590/S0066-782X2011005000045</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Artigos Originais</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Impacto da insufici&#234;ncia renal cr&#244;nica na efic&#225;cia de stents farmacol&#243;gicos: estudo de seguimento de longo prazo</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Gomes</surname>
            <given-names>Vitor Os&#243;rio</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Blaya</surname>
            <given-names>Patr&#237;cia</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
          <xref ref-type="aff" rid="aff02"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Lasevitch</surname>
            <given-names>Ricardo</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Oliveira</surname>
            <given-names>Denise</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Hickmann</surname>
            <given-names>Patr&#237;cia</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Smidt</surname>
            <given-names>Lu&#237;s</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Polanczyk</surname>
            <given-names>Carisi</given-names>
          </name>
          <xref ref-type="aff" rid="aff02"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Caramori</surname>
            <given-names>Paulo</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
          <xref ref-type="aff" rid="aff02"/>
        </contrib>
      </contrib-group>
      <aff id="aff01">
        <addr-line>
          <named-content content-type="city">Porto Alegre</named-content>
          <named-content content-type="state">Rio Grande do Sul</named-content>
        </addr-line>
        <institution content-type="orgname">Pontif&#237;cia Universidade Cat&#243;lica do Rio Grande do Sul</institution>
        <institution content-type="orgdiv1">Hospital S&#227;o Lucas </institution>
        <country country="BR">Brazil</country>
      </aff>
      <aff id="aff02">
        <addr-line>
          <named-content content-type="city">Porto Alegre</named-content>
          <named-content content-type="state">Rio Grande do Sul</named-content>
        </addr-line>
        <institution content-type="orgname">Universidade Federal do Rio Grande do Sul</institution>
        <country country="BR">Brazil</country>
      </aff>
      <pub-date date-type="collection" publication-format="electronic">
        <month>05</month>
        <year>2011</year>
      </pub-date>
      <volume>96</volume>
      <issue>5</issue>
      <fpage>346</fpage>
      <lpage>352</lpage>
      <history>
        <date date-type="accepted">
          <day>29</day>
          <month>11</month>
          <year>2010</year>
        </date>
        <date date-type="rev-recd">
          <day>17</day>
          <month>11</month>
          <year>2010</year>
        </date>
        <date date-type="received">
          <day>23</day>
          <month>08</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>FUNDAMENTO: Pacientes com Insufici&#234;ncia Renal Cr&#244;nica (IRC) submetidos &#224; angioplastia coron&#225;ria apresentam maiores taxas de revasculariza&#231;&#227;o da les&#227;o alvo (RLA) e mortalidade. Os stents farmacol&#243;gicos (SF) est&#227;o associados com taxas menores de reestenose, quando comparados aos stents n&#227;o farmacol&#243;gicos (SNF), embora em pacientes com IRC os dados da efic&#225;cia e seguran&#231;a do SF sejam limitados. OBJETIVO: Buscamos avaliar a seguran&#231;a e efic&#225;cia dos SF em pacientes com IRC significante, quando comparados a pacientes com fun&#231;&#227;o renal normal em um registro da "vida real". M&#201;TODOS: 504 pacientes submetidos &#224; interven&#231;&#227;o coronariana percut&#226;nea com SF em dois centros foram inclu&#237;dos. Os desfechos foram estratificados baseados na presen&#231;a de IRC, definida como taxa de filtra&#231;&#227;o glomerular basal &lt; 60 ml/min/1,73 m&#178;. RESULTADOS: O acompanhamento m&#233;dio foi de 22,7 meses. A IRC estava presente em 165 pacientes (32,7%). Pacientes com IRC eram mais velhos, tinham mais hipertens&#227;o e diabete. Pacientes com IRC apresentaram maior incid&#234;ncia de morte (12,3% vs 2,4%, p &lt; 0,001) e infarto do mioc&#225;rdio (IM) (7,4% vs 3,3%, p = 0,04), quando comparados aos pacientes sem IRC. Taxas de RLA foram similares entre os grupos (4.8% vs 5.6%, p = 0,7, pacientes com e sem IRC, respectivamente). Preditores independentes de morte foram a IRC (HR 6,93; 2,4 - 19,5, p &lt; 0,001), tabagismo atual (HR 3,66; 1,20 - 11,10, p = 0,02) e diabete (HR 2,66; 1,3 - 6,60, p = 0,045). CONCLUS&#195;O: Neste registro, a interven&#231;&#227;o coronariana com SF em pacientes com IRC foi associada com RLA similar comparada aos pacientes sem IRC, demonstrando a efic&#225;cia dos FS na preven&#231;&#227;o da reestenose intra-stent nessa popula&#231;&#227;o de pacientes. A IRC foi relacionada a um aumento significativo das taxas de IM e mortalidade.</p>
      </abstract>
      <kwd-group xml:lang="pt" kwd-group-type="author-generated">
        <kwd>Insufici&#234;ncia renal cr&#244;nica</kwd>
        <kwd>stents farmacol&#243;gicos</kwd>
        <kwd>efic&#225;cia</kwd>
        <kwd>seguimentos</kwd>
      </kwd-group>
      <pub-date publication-format="electronic" date-type="pub">
        <day>15</day>
        <month>04</month>
        <year>2011</year>
      </pub-date>
    </article-meta>
  </front>
  <body>
    <p>
      <bold>ARTIGO ORIGINAL</bold>
    </p>
    <p>Impacto da insufici&#234;ncia renal cr&#244;nica na efic&#225;cia de <italic><bold>stents</bold></italic> farmacol&#243;gicos: estudo de seguimento de longo prazo</p>
    <p>
      <bold>Vitor Os&#243;rio Gomes<sup>I</sup>; Patr&#237;cia Blaya<sup>I,II</sup>; Ricardo Lasevitch<sup>I</sup>; Denise Oliveira<sup>I</sup>; Patr&#237;cia Hickmann<sup>I</sup>; Lu&#237;s Smidt<sup>I</sup>; Carisi Polanczyk<sup>II</sup>; Paulo Caramori<sup>I,II</sup></bold>
    </p>
    <p><sup>I</sup>Hospital S&#227;o Lucas - PUCRS, Porto Alegre, RS - Brasil </p>
    <p><sup>II</sup>Programa de P&#243;s-gradua&#231;&#227;o em Cardiologia - UFRGS, Porto Alegre, RS - Brasil</p>
    <p>
      <xref ref-type="corresp" rid="end">Correspond&#234;ncia</xref>
    </p>
    <p>
      <bold>RESUMO</bold>
    </p>
    <p><bold>FUNDAMENTO:</bold> Pacientes com Insufici&#234;ncia Renal Cr&#244;nica (IRC) submetidos &#224; angioplastia coron&#225;ria apresentam maiores taxas de revasculariza&#231;&#227;o da les&#227;o alvo (RLA) e mortalidade. Os <italic>stents</italic> farmacol&#243;gicos (SF) est&#227;o associados com taxas menores de reestenose, quando comparados aos <italic>stents</italic> n&#227;o farmacol&#243;gicos (SNF), embora em pacientes com IRC os dados da efic&#225;cia e seguran&#231;a do SF sejam limitados. </p>
    <p><bold>OBJETIVO:</bold> Buscamos avaliar a seguran&#231;a e efic&#225;cia dos SF em pacientes com IRC significante, quando comparados a pacientes com fun&#231;&#227;o renal normal em um registro da "vida real". </p>
    <p><bold>M&#201;TODOS:</bold> 504 pacientes submetidos &#224; interven&#231;&#227;o coronariana percut&#226;nea com SF em dois centros foram inclu&#237;dos. Os desfechos foram estratificados baseados na presen&#231;a de IRC, definida como taxa de filtra&#231;&#227;o glomerular basal &lt; 60 ml/min/1,73 m&#178;. </p>
    <p><bold>RESULTADOS:</bold> O acompanhamento m&#233;dio foi de 22,7 meses. A IRC estava presente em 165 pacientes (32,7%). Pacientes com IRC eram mais velhos, tinham mais hipertens&#227;o e diabete. Pacientes com IRC apresentaram maior incid&#234;ncia de morte (12,3% <italic>vs</italic> 2,4%, p &lt; 0,001) e infarto do mioc&#225;rdio (IM) (7,4% <italic>vs</italic> 3,3%, p = 0,04), quando comparados aos pacientes sem IRC. Taxas de RLA foram similares entre os grupos (4.8% <italic>vs</italic> 5.6%, p = 0,7, pacientes com e sem IRC, respectivamente). Preditores independentes de morte foram a IRC (HR 6,93; 2,4 - 19,5, p &lt; 0,001), tabagismo atual (HR 3,66; 1,20 - 11,10, p = 0,02) e diabete (HR 2,66; 1,3 - 6,60, p = 0,045). </p>
    <p><bold>CONCLUS&#195;O:</bold> Neste registro, a interven&#231;&#227;o coronariana com SF em pacientes com IRC foi associada com RLA similar comparada aos pacientes sem IRC, demonstrando a efic&#225;cia dos FS na preven&#231;&#227;o da reestenose intra-<italic>stent</italic> nessa popula&#231;&#227;o de pacientes. A IRC foi relacionada a um aumento significativo das taxas de IM e mortalidade.</p>
    <p><bold>Palavras-chave:</bold> Insufici&#234;ncia renal cr&#244;nica, <italic>stents</italic> farmacol&#243;gicos, efic&#225;cia, seguimentos.</p>
    <p>
      <bold>Introdu&#231;&#227;o</bold>
    </p>
    <p>A insufici&#234;ncia renal cr&#244;nica (IRC) &#233; um importante problema de sa&#250;de p&#250;blica no mundo todo. Existe uma forte associa&#231;&#227;o entre a IRC e a preval&#234;ncia de doen&#231;a arterial coronariana (DAC) e mortalidade<sup>1</sup>. Entre pacientes com insufici&#234;ncia renal cr&#244;nica terminal (IRCT), a mortalidade card&#237;aca &#233; de 10 a 30 vezes maior que na popula&#231;&#227;o em geral. O mecanismo desta associa&#231;&#227;o n&#227;o &#233; inteiramente conhecido, mas uma maior preval&#234;ncia de fatores de risco tradicionais na popula&#231;&#227;o, como idade avan&#231;ada, hipertens&#227;o e diabete, contribui para a aterosclerose acelerada<sup>2-4</sup>.</p>
    <p>Ap&#243;s a interven&#231;&#227;o coronariana percut&#226;nea (ICP) com <italic>stents</italic> n&#227;o-farmacol&#243;gicos (SNF), pacientes com IRC tiveram um aumento na incid&#234;ncia de reestenose e eventos card&#237;acos quando comparados &#224; pacientes sem disfun&#231;&#227;o renal<sup>5-7</sup>. Contudo, mesmo considerando os resultados limitados, a ICP &#233; uma alternativa muito importante no tratamento de pacientes com IRC que possam apresentar um risco cir&#250;rgico aumentado e que apresentem angina limitante, apesar do tratamento m&#233;dico otimizado<sup>7</sup>.</p>
    <p><italic>Stents</italic> farmacol&#243;gicos (SF) reduziram a incid&#234;ncia de reestenose e a necessidade de revasculariza&#231;&#227;o futura quando comparados aos SNF. H&#225; escassez de dados sobre a seguran&#231;a e efic&#225;cia do SF em pacientes com IRC, considerando que essa popula&#231;&#227;o &#233; frequentemente exclu&#237;da de grandes estudos cl&#237;nicos<sup>8-10</sup>.</p>
    <p>O objetivo deste estudo foi avaliar a efic&#225;cia e seguran&#231;a dos FS em pacientes com IRC significante, quando comparados &#224; pacientes com fun&#231;&#227;o renal normal em um registro da "vida real". </p>
    <p>
      <bold>M&#233;todos</bold>
    </p>
    <p>
      <bold>Popula&#231;&#227;o do estudo</bold>
    </p>
    <p>A popula&#231;&#227;o do estudo consistiu em 611 pacientes consecutivos submetidos &#224; ICP com SF entre junho de 2002 e junho de 2006 em dois hospitais terci&#225;rios em Porto Alegre, Brasil. Um total de 504 pacientes foi inclu&#237;do nesta an&#225;lise, pois os mesmos tinham medidas de creatinina s&#233;ricas dispon&#237;veis de at&#233; 30 dias antes da interven&#231;&#227;o coronariana. </p>
    <p>A IRC foi definida como a taxa de filtra&#231;&#227;o glomerular (TFG) &lt; 60 ml/min/1,73 m&#178;, um valor de corte previamente proposto pela <italic>National Foundation's Kidney Disease Outcome Quality Initiative Advisory Board </italic>(K/DOQI), para identificar pacientes com insufici&#234;ncia renal moderada<sup>11</sup>. Em conformidade, os pacientes foram divididos em 2 grupos: 1) pacientes com a TFG <underline>&gt;</underline> 60 ml/min/1,73 m&#178; e 2) pacientes com GFR &lt; 60 ml/min/1,73 m&#178;</p>
    <p>A TFG foi calculada pela equa&#231;&#227;o da modifica&#231;&#227;o da dieta na doen&#231;a renal (MDRD): TFG <italic>Estimada</italic> = 186 x (creatinina s&#233;rica)<sup>-1.154</sup> x (idade)<sup>- 0.203 </sup>x (0.742 se for do sexo feminino) x (1.210 se negro/a), onde a creatinina &#233; medida em mg/dl, idade em anos e a TFG &#233; expressa em ml/min/1,73 m&#178; <sup>12,13</sup>. </p>
    <p>Este estudo foi aprovado pelo Comit&#234; de &#201;tica e Pesquisa Institucional local de ambos os hospitais. </p>
    <p>Este estudo foi financiado por um fundo para educa&#231;&#227;o irrestrito do Boston Scientific, Cordis Corporation e Medtronic. Estas empresas n&#227;o tiveram acesso aos dados e n&#227;o tem o direito de revisar o artigo antes de sua publica&#231;&#227;o. </p>
    <p>
      <bold>Defini&#231;&#245;es de <italic>endpoints</italic> e acompanhamento cl&#237;nico</bold>
    </p>
    <p>O infarto do mioc&#225;rdio (IM) foi definido como uma eleva&#231;&#227;o da fra&#231;&#227;o creatina quinase-MB de tr&#234;s vezes acima do limite da varia&#231;&#227;o normal<sup>14</sup>. A taxa de revasculariza&#231;&#227;o do vaso-alvo (RVA) foi definida como uma revasculariza&#231;&#227;o percut&#226;nea repetida ou cir&#250;rgica do vaso tratado. A revasculariza&#231;&#227;o da les&#227;o alvo (RLA) foi definida como uma revasculariza&#231;&#227;o percut&#226;nea ou cir&#250;rgica da les&#227;o-&#237;ndice durante o acompanhamento. Um evento adverso card&#237;aco maior (MACE) foi definido como um <italic>endpoint</italic> composto de morte card&#237;aca, IM n&#227;o fatal ou RVA durante o acompanhamento. A defini&#231;&#227;o de trombose de <italic>stent</italic> (TS) foi baseada nos crit&#233;rios estabelecidos pelo <italic>Academic Research Consortium </italic>(ARC)<sup>15</sup>. </p>
    <p>O sucesso angiogr&#225;fico foi definido como estenose &lt; 20% e fluxo TIMI 3 ao fim do procedimento. O sucesso cl&#237;nico foi definido como sucesso angiogr&#225;fico e a aus&#234;ncia de complica&#231;&#245;es cl&#237;nicas como morte, IM, revasculariza&#231;&#227;o urgente e derrame.</p>
    <p>Para pacientes com mais de uma interven&#231;&#227;o durante o per&#237;odo de acompanhamento do estudo, somente a primeira interven&#231;&#227;o foi considerada para an&#225;lise dos <italic>endpoints</italic>. </p>
    <p>O tipo de ST usado durante o procedimento coron&#225;rio foi deixado a crit&#233;rio do cardiologista intervencionista. </p>
    <p>O acompanhamento clinico foi feito atrav&#233;s de entrevistas telef&#244;nicas com o paciente, revis&#227;o dos hist&#243;ricos dos pacientes ambulatoriais e contato com o m&#233;dico assistente. Todos os eventos cl&#237;nicos foram adjudicados pela an&#225;lise das fontes de documenta&#231;&#227;o por um cardiologista cego para os outros dados cl&#237;nicos.</p>
    <p>
      <bold>An&#225;lise angiogr&#225;fica coronariana quantitativa</bold>
    </p>
    <p>Os angiogramas coronarianos basais e p&#243;s-procedimento obtidos foram analisados por um cardiologista experiente. A angiografia coronariana quantitativa off-line da interven&#231;&#227;o &#237;ndice foi executada usando o cateter-guia para calibra&#231;&#227;o da magnifica&#231;&#227;o da imagem (<italic>CardioNow Websend DICOM Study Sharing Software</italic>, HeartLab, Inc., Westerly, Rhode Island). Foram medidos o di&#226;metro luminal m&#237;nimo e di&#226;metro do vaso de refer&#234;ncia antes e depois da interven&#231;&#227;o a partir de corte &#250;nico mostrando o menor di&#226;metro luminal. </p>
    <p>
      <bold>An&#225;lise estat&#237;stica</bold>
    </p>
    <p>A an&#225;lise estat&#237;stica foi realizada com o <italic>software</italic> SPSS 13.0 (SPSS Inc, Chicago, Illinois). Dados absolutos foram apresentados como frequ&#234;ncias (%) e comparados pelo teste Qui-quadrado.Vari&#225;veis cont&#237;nuas foram apresentadas como m&#233;dia &#177; desvio padr&#227;o (DP) e comparadas usando o teste <italic>t</italic> de <italic>student</italic> ou o teste U de Mann-Whitney quando apropriado. Resultados cl&#237;nicos foram calculados por qui-quadrado. Os tempos para ocorr&#234;ncia de morte, IM, trombose e revasculariza&#231;&#227;o nos 2 grupos s&#227;o apresentados como curvas de Kaplan-Meier e comparados usando-se o teste log-rank. Caracter&#237;sticas basais significantes, preditivas de morte e RLA foram identificadas usando an&#225;lises multivariadas de Cox, selecionando vari&#225;veis pelo m&#233;todo Backward Wald. Para todas as an&#225;lises, um valor de p bilateral &lt; 0,05 foi considerado para indicar diferen&#231;as significantes. </p>
    <p>
      <bold>Resultados</bold>
    </p>
    <p>A m&#233;dia do acompanhamento cl&#237;nico foi de 22,6 &#177; 13,0 meses, com uma varia&#231;&#227;o de 6,0 a 63,5 meses e estava dispon&#237;vel em 98,2% dos pacientes. Havia 181 mulheres e 323 homens. A m&#233;dia da idade na popula&#231;&#227;o de estudo era de 63,7 &#177; 11,0, variando de 30 a 90 anos de idade. A creatinina s&#233;rica m&#233;dia e a TFG eram 1,22 mg/dl e 69,8 ml/min/1,73 m&#178;, respectivamente. </p>
    <p>Dos 504 pacientes inclu&#237;dos nessa an&#225;lise, 339 (67,3%) apresentaram TFG <underline>&gt;</underline> 60 ml/min/1,73 m&#178;, e 165 (32,7%) apresentaram TFG &lt; 60 ml/min/1,73 m&#178;. Dez pacientes apresentavam insufici&#234;ncia renal em est&#225;gio terminal na di&#225;lise. A creatinina s&#233;rica m&#233;dia dos grupos foi de 0,95 &#177; 0,17 mg/dl e 1,76 &#177; 1,38 mg/dl, respectivamente.</p>
    <p>As caracter&#237;sticas cl&#237;nicas de ambos os grupos s&#227;o mostradas na <xref ref-type="table" rid="tab01">Tabela 1</xref>. Pacientes com IRC, comparados aos pacientes sem IRC, eram significativamente mais velhos (68,6 &#177; 10 anos <italic>vs</italic> 61,2 &#177; 9 anos, p &lt; 0,001), com maior probabilidade de serem mulheres (50,3% <italic>vs</italic> 28,9%, p &lt; 0,001), tinham hipertens&#227;o (88,8% <italic>vs</italic> 72,8%, p &lt; 0,001), diabete (47.5% <italic>vs</italic> 31.5%, p = 0,001), e eram menos propensos a usar aspirina (74,5% <italic>vs</italic> 87,4%, p &lt; 0,001), ou serem fumantes atuais (5,7% <italic>vs</italic> 10%, p = 0,02).</p>
    <table-wrap id="tab01">
      <graphic xlink:href="1678-4170-abc-96-05-0346-00045-gt01.jpg"/></table-wrap>
    <p>Caracter&#237;sticas angiogr&#225;ficas e procedurais dos dois grupos s&#227;o apresentadas na <xref ref-type="table" rid="tab02">Tabela 2</xref>. A taxa de sucesso angiogr&#225;fico foi alta e similar nos dois grupos. Comparados aos pacientes sem IRC, aqueles com IRC tiveram maior probabilidade de serem submetidos ao uso de <italic>stent</italic> direto (26,6% <italic>vs</italic> 35,7%, p = 0,05). Pela angiografia coronariana quantitativa, o di&#226;metro luminal m&#237;nimo tendeu a ser maior na condi&#231;&#227;o basal (0,9 &#177; 0,72 mm <italic>vs</italic> 1,0 &#177; 0,42 mm, p = 0,06) e ap&#243;s o <italic>stent</italic> (2,7 &#177; 0,48 mm <italic>vs</italic> 2,8 &#177; 0.49 mm, p = 0,05) nos pacientes com IRC, mas o ganho agudo foi similar. Outras caracter&#237;sticas das les&#245;es foram similares entre os grupos. </p>
    <table-wrap id="tab02">
      <graphic xlink:href="1678-4170-abc-96-05-0346-00045-gt02.jpg"/></table-wrap>
    <p>A incid&#234;ncia de eventos cardiovasculares adversos durante a hospitaliza&#231;&#227;o foi alta em pacientes com IRC. Pacientes com IRC apresentaram sucesso cl&#237;nico reduzido (92,1% <italic>vs</italic> 98,2%, p = 0,001), com aumento nas taxas de IM (3,7% <italic>vs</italic> 0,6%, p = 0,01) e morte (3,7% <italic>vs</italic> 0,3%, p = 0,003). Nenhum paciente sofreu derrame durante a hospitaliza&#231;&#227;o. </p>
    <p>Os resultados cl&#237;nicos de longo prazo s&#227;o apresentados na <xref ref-type="table" rid="tab03">Tabela 3</xref>. As an&#225;lises de sobreviv&#234;ncia de Kaplan-Meier para morte, infarto do mioc&#225;rdio, revasculariza&#231;&#227;o da les&#227;o alvo, e trombose de <italic>stent</italic> definitiva s&#227;o apresentadas na <xref ref-type="fig" rid="fig01">Figura 1</xref>. Pacientes com IRC apresentaram maior incid&#234;ncia de morte e morte card&#237;aca (12,3% <italic>vs</italic> 2,4%, p &lt; 0,001, e 6,1% <italic>vs</italic> 1,2%, p = 0,002, respectivamente) quando comparados com pacientes sem IRC. A incid&#234;ncia de IM tamb&#233;m foi alta em pacientes com IRC (7,4% <italic>vs</italic> 3,3%, p = 0,04). Contudo, as taxas de RVA e RLA foram similares entre os grupos (12,5%, <italic>vs</italic> 11,3%, p = 0,7, e 4,8% <italic>vs</italic> 5,6%, p = 0,7, respectivamente pacientes com IRC e sem IRC). A taxa de trombose de <italic>stent</italic> definitiva foi similar nos dois grupos (1,9% <italic>vs</italic> 1,2%, p = 0,21, pacientes com IRC e sem IRC, respectivamente).</p>
    <table-wrap id="tab03">
      <graphic xlink:href="1678-4170-abc-96-05-0346-00045-gt03.jpg"/></table-wrap>
    <fig id="fig01">
      <graphic xlink:href="1678-4170-abc-96-05-0346-00045-gf01.jpg"/></fig>
    <p>Para determinar se a IRC era um preditor independente de RLA e morte ap&#243;s SF, n&#243;s executamos an&#225;lise multivariada <italic>backward</italic> usando o modelo de riscos proporcionais de Cox. Vari&#225;veis consideradas para o modelo incluem IRC, idade, sexo, diabete melito, tabagismo atual, hipertens&#227;o, hipercolesterolemia, comprimento da les&#227;o, di&#226;metro luminal m&#237;nimo, n&#250;mero de vasos com doen&#231;a arterial coronariana. O comprimento de les&#227;o (HR 1,06; IC95% 1,007 - 1,070, p = 0,02) foi o &#250;nico preditor independente da revasculariza&#231;&#227;o da les&#227;o alvo subsequente. Preditores independentes de morte foram IRC (HR 6,93; IC95% 2,4 - 19.5, p &lt; 0,001), tabagismo atual (HR 3,66; IC95% 1,20 - 11,10, p = 0,02) e diabete (HR 2,66; IC95% 1,03 - 6,60, p = 0,045).</p>
    <p>
      <bold>Discuss&#227;o</bold>
    </p>
    <p>Esse &#233; um registro de pacientes consecutivos de dois centros que foram submetidos &#224; ICP com SF, sem crit&#233;rios de exclus&#227;o e que, portanto, representa a pr&#225;tica do "mundo real". At&#233; onde sabemos, o presente estudo tem o mais longo per&#237;odo de acompanhamento de pacientes com IRC ap&#243;s a implanta&#231;&#227;o do SF.</p>
    <p>O principal achado deste estudo &#233; que, embora os pacientes com IRC tenham apresentado maior incid&#234;ncia de morte, IM e MACE comparados com pacientes com fun&#231;&#245;es renais preservadas, n&#227;o h&#225; associa&#231;&#227;o entre a presen&#231;a de IRC e o risco de revasculariza&#231;&#227;o ap&#243;s a implanta&#231;&#227;o do SF. Isto demonstra que o uso do SF permanece t&#227;o efetivo em pacientes com IRC quanto em pacientes sem IRC por at&#233; cinco anos.</p>
    <p>Pacientes com IRC apresentam aterosclerose acelerada, maior incid&#234;ncia de fatores de risco de DAC e DAC mais grave<sup>16</sup>. Diversos estudos anteriores observaram que uma IRC m&#233;dia a moderada est&#225; associada com taxas maiores de morte por qualquer causa e morte cardiovascular<sup>17-19</sup>. Ap&#243;s a ICP, foi observado que a mortalidade est&#225; diretamente relacionada &#224; gravidade da IRC. Al&#233;m disso, uma IRC moderada aumenta o risco de nefropatia induzida por contraste, IM recorrente, insufici&#234;ncia card&#237;aca e arritmias<sup>18-21</sup>. Nosso estudo encontrou um aumento na preval&#234;ncia de diabete, hipertens&#227;o, e idade avan&#231;ada associados com um aumento da mortalidade entre os pacientes com IRC. A an&#225;lise multivariada confirmou a IRC, tabagismo atual e diabete como preditores independentes de mortalidade por todas as causas.</p>
    <p>Estudos anteriores comparando pacientes com IRC e pacientes sem IRC submetidos a ICP com SF, observaram que a mortalidade &#233; uniformemente maior em pacientes com IRC<sup>22-24</sup>. Al&#233;m disso, pacientes com IRC apresentaram um aumento da mortalidade apesar do uso de SF ou SNF<sup>22,23,25</sup>. Somente um estudo relatou uma taxa de mortalidade menor em pacientes com IRC submetidos a ICP com SF ap&#243;s 1 ano<sup>25</sup>.</p>
    <p>Encontramos uma maior incid&#234;ncia de MACE em pacientes com IRC, primariamente devido &#224;s altas taxas de mortalidade e IM. Esse achado difere do estudo Nakazawa, onde a maior incid&#234;ncia de MACE ap&#243;s a implanta&#231;&#227;o do SF em pacientes com IRC ocorria principalmente devido &#224; maior incid&#234;ncia de RVA<sup>24</sup>. Naquele estudo, o acompanhamento angiogr&#225;fico de rotina foi executado oito meses ap&#243;s o <italic>stenting</italic> e pode ter contribu&#237;do para um aumento na taxa de revasculariza&#231;&#227;o. </p>
    <p>Poucos estudos avaliaram as taxas de reestenose e revasculariza&#231;&#227;o ap&#243;s a interven&#231;&#227;o coronariana percut&#226;nea com SF em pacientes com IRC. Meta-an&#225;lises de grandes estudos cl&#237;nicos randomizados n&#227;o foram capazes de avaliar essa quest&#227;o, considerando que a maior parte dos estudos excluiu os pacientes com insufici&#234;ncia renal<sup>26</sup>. Da mesma forma, meta-an&#225;lises de redes maiores impedem an&#225;lises de subgrupos devido &#224; falta de dados individuais dos pacientes<sup>27</sup>.</p>
    <p>Em nosso estudo, a taxa de RLA foi baixa, independentemente da fun&#231;&#227;o renal. Esse achado &#233; similar &#224; de outros estudos em pacientes com IRC moderada, que relataram uma diminui&#231;&#227;o na incid&#234;ncia de revasculariza&#231;&#227;o ap&#243;s a implanta&#231;&#227;o do SF quando comparado ao SNF<sup>22,23,25</sup>. Uma sub-an&#225;lise do estudo TAXUS-IV<sup>25</sup>, de pacientes com insufici&#234;ncia renal moderada basal (TFG &lt; 60 ml/min), randomizados para o <italic>stent</italic> eluidor de paclitaxel (n = 123) ou SNF (n = 100), demonstrou taxas significativamente menores de RLA (3,3% <italic>vs</italic> 12,2%, p = 0,01) e RVA (6,6% <italic>vs</italic> 15,2%, p = 0,04). Por outro lado, um pequeno estudo de caso-controle incluindo pacientes com IRC apresentou taxas similares de revasculariza&#231;&#227;o com SF ou SNF<sup>28</sup>.</p>
    <p>Kuchulakanti e cols.<sup>29</sup>, em um estudo envolvendo 76 pacientes com IRC e 1466 controles, relataram baixas taxas de revasculariza&#231;&#227;o ap&#243;s a implanta&#231;&#227;o do SF nos dois grupos. A taxa de RVA em seis meses foi significativamente maior nos pacientes com IRC do que nos pacientes sem IRC (7% <italic>vs</italic> 4%, p &lt; 0,001) (23). Outro estudo avaliando a revasculariza&#231;&#227;o envolveu pacientes que foram divididos em tr&#234;s grupos: TFG <underline>&gt;</underline> 60 ml/min; TFG &lt; 60 ml/min e pacientes em hemodi&#225;lise. O acompanhamento angiogr&#225;fico foi realizado aos oito meses. Ap&#243;s a implanta&#231;&#227;o do SF, a taxa de RVA aumentou significativamente em pacientes em hemodi&#225;lise, quando comparado a pacientes com IRC moderada e pacientes sem IRC (32,3%, 13% e 9,8%, p = 0,002 respectivamente)<sup>24</sup>.</p>
    <p>Tem sido demonstrado que a IRC &#233; um fator de risco independente para a trombose de <italic>stent</italic> ap&#243;s a implanta&#231;&#227;o de SF em alguns<sup>29,30</sup>, mas n&#227;o em todos os estudos<sup>31</sup>. Em nosso estudo, observamos que a incid&#234;ncia de trombose de <italic>stent</italic> n&#227;o estava significativamente aumentada em pacientes com IRC. &#201; poss&#237;vel que a falta de signific&#226;ncia observada em nosso estudo esteja relacionada ao reduzido poder estat&#237;stico para avaliar esse evento de baixa incid&#234;ncia.</p>
    <p>Um artigo recentemente publicado, embora limitado a pacientes dos EUA e n&#227;o exclusivamente &#224; procedimentos de SF, com 1 ano de acompanhamento cl&#237;nico, apresentou resultados similares aos do nosso estudo. Pacientes com IRC apresentaram maior incid&#234;ncia de morte e IM, e taxas de RLA e trombose de <italic>stent</italic> n&#227;o foram influenciados pela presen&#231;a da IRC<sup>32</sup>. </p>
    <p>
      <bold>Limita&#231;&#245;es do estudo</bold>
    </p>
    <p>Os achados desse estudo devem ser interpretados sob a luz de algumas limita&#231;&#245;es. O n&#250;mero de pacientes com doen&#231;a renal terminal em hemodi&#225;lise era muito pequeno, e portanto nenhuma conclus&#227;o pode ser tirada, apesar da seguran&#231;a e efic&#225;cia do SF nessa popula&#231;&#227;o. Al&#233;m disso, a falta de um grupo de controle de <italic>stent</italic> n&#227;o farmacol&#243;gico n&#227;o nos permitiu comparar resultados entre SF e SNF. </p>
    <p>Finalmente, como os pacientes n&#227;o foram submetidos &#224; seguimento mandat&#243;rio com teste de esfor&#231;o ou angiografia coronariana, isquemia silenciosa e reestenose podem ter sido sub-diagnosticadas. </p>
    <p>
      <bold>Conclus&#227;o</bold>
    </p>
    <p>Nesse registro de "mundo real", a ICP com SF em pacientes com IRC esteve associada com revasculariza&#231;&#227;o de les&#227;o-alvo, quando comparados com pacientes sem IRC, indicando que o SF preserva o efeito ben&#233;fico na preven&#231;&#227;o de reestenose intra-<italic>stent</italic> nessa popula&#231;&#227;o de alto risco. De qualquer forma, a IRC estava associada com taxas mais altas de IM e mortalidade, demonstrando que desfechos cl&#237;nicos em pacientes com IRC, mesmo ap&#243;s ICP bem sucedida, dependem da interrela&#231;&#227;o de outras comorbidades.</p>
    <p>
      <fn id="end" fn-type="corresp">
        <p>Correspond&#234;ncia:</p>
        <p>Vitor Os&#243;rio Gomes </p>
        <p> Av. Lageado, 969/401 - Petr&#243;polis </p>
        <p> 90460-110 - Porto Alegre, RS - Brasil </p>
        <p> E-mail: </p>
        <p><email xlink:href="vigomes@cardiol.br">vigomes@cardiol.br</email>, </p>
        <p>
          <email xlink:href="vigomes@terra.com.br">vigomes@terra.com.br</email>
        </p>
      </fn>
    </p>
    <p> Artigo recebido em 23/08/10; revisado recebido em 17/11/10; aceito em 29/11/10</p>
    <p>Full texts in English - <ext-link ext-link-type="uri" xlink:href="http://www.arquivosonline.com.br">http://www.arquivosonline.com.br</ext-link></p>
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  <sub-article article-type="translation" id="TRen" xml:lang="en">
    <front-stub>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Original Articles</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title xml:lang="en">Impact of chronic kidney disease on the efficacy of drug-eluting stents: long-term follow-up study</article-title>
      </title-group>
      <abstract xml:lang="en">
        <p>BACKGROUND: Patients with chronic kidney disease (CKD) submitted to coronary angioplasty have higher rates of target lesion revascularization (TLR) and mortality. Drug-eluting stents (DES) are associated with a lower rate of restenosis, compared to bare metal stents (BMS), although data on DES efficacy and safety is limited in patients with CKD. OBJECTIVE: We sought to evaluate the safety and efficacy of DES in patients with significant CKD as compared to patients without normal renal function in a real world registry. METHODS: 504 patients who underwent percutaneous coronary intervention with DES in two centers were included. Outcomes were stratified based on the presence of CKD, defined as a baseline glomerular filtration rate (GFR) &lt; 60 ml/min/1.73 m&#178;. RESULTS: The mean follow-up was 22.7 months. CKD was present in 165 patients (32.7%). Patients with CKD were older, had a higher incidence of hypertension and diabetes. CKD patients presented an increased incidence of death (12.3% vs 2.4%, p &lt; 0.001) and myocardial infarction (MI) (7.4% vs 3.3%, p = 0.04) compared to patients without CKD. TLR rates were similar between groups (4.8% vs 5.6%, p = 0.7, CKD and no CKD patients, respectively). Independent predictors of death were CKD (HR 6.93; 2.4 - 19.5, p &lt; 0.001), current smoking (HR 3.66; 1.20 - 11.10, p = 0.02) and diabetes (HR 2.66; 1.03 - 6.60, p = 0.045). CONCLUSION: In this registry, coronary intervention with DES in patients with CKD was associated with similar TLR compared to patients without CKD, demonstrating the efficacy of DES in preventing in-stent restenosis in this patient population. CKD was related to significantly increased MI and mortality rates.</p>
      </abstract>
      <kwd-group xml:lang="en">
        <kwd>Renal insufficiency</kwd>
        <kwd>chronic</kwd>
        <kwd>drug-eluting stents</kwd>
        <kwd>efficacy</kwd>
        <kwd>follow-up studies</kwd>
      </kwd-group>
    </front-stub>
    <body>
      <p>
        <bold>ORIGINAL ARTICLE</bold>
      </p>
      <p><undefined id="title-body2"/>Impact of chronic kidney disease on the efficacy of drug-eluting stents: long-term follow-up study</p>
      <p>
        <bold>Vitor Os&#243;rio Gomes<sup>I</sup>; Patr&#237;cia Blaya<sup>I,II</sup>; Ricardo Lasevitch<sup>I</sup>; Denise Oliveira<sup>I</sup>; Patr&#237;cia Hickmann<sup>I</sup>; Lu&#237;s Smidt<sup>I</sup>; Carisi Polanczyk<sup>II</sup>; Paulo Caramori<sup>I,II</sup></bold>
      </p>
      <p><sup>I</sup>Hospital S&#227;o Lucas - PUCRS, Porto Alegre, RS - Brazil</p>
      <p><sup>II</sup>Programa de P&#243;s-gradua&#231;&#227;o em Cardiologia - UFRGS, Porto Alegre, RS - Brazil</p>
      <p>Mailing address</p>
      <p>
        <bold>ABSTRACT</bold>
      </p>
      <p><bold>BACKGROUND: </bold>Patients with chronic kidney disease (CKD) submitted to coronary angioplasty have higher rates of target lesion revascularization (TLR) and mortality. Drug-eluting stents (DES) are associated with a lower rate of restenosis, compared to bare metal stents (BMS), although data on DES efficacy and safety is limited in patients with CKD.</p>
      <p><bold>OBJECTIVE: </bold>We sought to evaluate the safety and efficacy of DES in patients with significant CKD as compared to patients without normal renal function in a real world registry.</p>
      <p><bold>METHODS: </bold>504 patients who underwent percutaneous coronary intervention with DES in two centers were included. Outcomes were stratified based on the presence of CKD, defined as a baseline glomerular filtration rate (GFR) &lt; 60 ml/min/1.73 m&#178;.</p>
      <p><bold>RESULTS: </bold>The mean follow-up was 22.7 months. CKD was present in 165 patients (32.7%). Patients with CKD were older, had a higher incidence of hypertension and diabetes. CKD patients presented an increased incidence of death (12.3% vs 2.4%, p &lt; 0.001) and myocardial infarction (MI) (7.4% vs 3.3%, p = 0.04) compared to patients without CKD. TLR rates were similar between groups (4.8% vs 5.6%, p = 0.7, CKD and no CKD patients, respectively). Independent predictors of death were CKD (HR 6.93; 2.4 - 19.5, p &lt; 0.001), current smoking (HR 3.66; 1.20 - 11.10, p = 0.02) and diabetes (HR 2.66; 1.03 - 6.60, p = 0.045).</p>
      <p><bold>CONCLUSION: </bold>In this registry, coronary intervention with DES in patients with CKD was associated with similar TLR compared to patients without CKD, demonstrating the efficacy of DES in preventing in-stent restenosis in this patient population. CKD was related to significantly increased MI and mortality rates. </p>
      <p><bold>Keywords: </bold>Renal insufficiency,chronic; drug-eluting stents; efficacy; follow-up studies.</p>
      <p>
        <bold>Introduction</bold>
      </p>
      <p>Chronic kidney disease (CKD) is an important worldwide public health issue. There is a strong association between CKD and coronary artery disease (CAD) prevalence and mortality<sup>1</sup>. Among patients with end-stage renal disease (ESRD), cardiac mortality is 10 to 30 times higher than in the general population. The mechanism of this association is not entirely known, but a higher prevalence of traditional risk factors in this population such as advanced age, hypertension and diabetes, contributes to accelerated atherosclerosis <sup>2-4</sup>.</p>
      <p>After percutaneous coronary intervention (PCI) with bare-metal stents (BMS), CKD patients had an increased incidence of restenosis and cardiac events when compared to patients without renal dysfunction<sup>5-7</sup>. However, even considering the limited results, PCI is a very important alternative in the treatment of CKD patients who may have increased surgical risk and present limiting angina despite of optimal medical treatment<sup>7</sup>.</p>
      <p>Drug-eluting stents (DES) have been found to reduce the incidence of restenosis and the need for future revascularization compared to BMS. There is a paucity of data on safety and efficacy of DES in CKD patients, as this population is often excluded from large clinical trials<sup>8-10</sup>. </p>
      <p>The aim of this study was to evaluate the efficacy and safety of DES in patients with significant CKD as compared to patients with normal renal function in a real-world registry.</p>
      <p>
        <bold>Methods</bold>
      </p>
      <p>
        <bold>Study population</bold>
      </p>
      <p>The study population consisted of 611 consecutive patients who underwent PCI with DES between June of 2002 and June of 2006 in two tertiary hospitals in Porto Alegre, Brazil. A total of 504 patients were included in this analysis, as they had available serum creatinine measurements up to 30 days before the coronary intervention. </p>
      <p>CKD was defined as the calculated glomerular filtration rate (GFR) &lt; 60 ml/min/1.73 m&#178;, a cut-off value previously proposed by the National Foundation's Kidney Disease Outcome Quality Initiative Advisory Board (K/DOQI) to identify patients with moderate renal failure<sup>11</sup>. In accordance, patients were divided into 2 groups: 1) patients with GFR <underline>&gt;</underline> 60 ml/min/1.73m&#178; and 2) patients with GFR &lt; 60 ml/min/1.73 m&#178;.</p>
      <p>The GFR was calculated by the equation of the modification of the diet in the renal disease (MDRD): Estimated GFR = 186 x (serum creatinine)<sup>-1.154</sup> x (age)<sup>- 0.203 </sup>x (0.742 if female) x (1.210 if black) , where creatinine is measured in mg/dl, age in years and GFR is expressed as ml/min/1.73 m&#178; <sup>12,13</sup>.</p>
      <p>This study was approved by the local Institutional Research and Ethics Committee of both hospitals.</p>
      <p>This study was supported by an unrestricted grant from Boston Scientific, Cordis Corporation and Medtronic. These companies do not have access to the data and do not have the right to review the article before publication.</p>
      <p>
        <bold>Endpoint definitions and clinical follow-up</bold>
      </p>
      <p>Myocardial infarction (MI) was defined as an elevation of the creatinine kinase-MB fraction of 3 times the upper limit of normal range<sup>14</sup>. Target vessel revascularization (TVR) was defined as repeated percutaneous or surgical revascularization of the treated vessel. Target lesion revascularization (TLR) was defined as percutaneous or surgical revascularization of the index lesion during follow-up. A major adverse cardiac event (MACE) was defined as a composite end-point of cardiac death, non-fatal MI or TVR during follow-up. The stent thrombosis definition was based on criteria set by the Academic Research Consortium (ARC)<sup>15</sup>. </p>
      <p>Angiographic success was defined as stenosis &lt; 20% and TIMI 3 flow at the end of the procedure. Clinical success was defined as angiographic success and absence of clinical complications such as death, MI, urgent revascularization and stroke.</p>
      <p>For patients with more than one intervention during the follow-up period of the study, only the first intervention was considered for endpoint analysis.</p>
      <p>The type of DES used during the coronary procedure was left to the discretion of the intervention cardiologist.</p>
      <p>The clinical follow-up was obtained by telephone interviews with the patient, from outpatient record review and contact with the assistant physician. All clinical events were adjudicated by analysis of source documentation by a cardiologist blinded for the remaining clinical data.</p>
      <p>
        <bold>Quantitative coronary angiographic analysis</bold>
      </p>
      <p>Coronary angiograms obtained at baseline and post-procedure were analyzed by an experienced cardiologist. Off-line quantitative coronary angiography of the index intervention was performed using the guiding catheter for magnification calibration (CardioNow Websend DICOM Study Sharing Software, HeartLab, Inc., Westerly, Rhode Island). Minimal luminal diameter and reference vessel diameter were measured before and after the intervention from a single matched view showing the smallest luminal diameter.</p>
      <p>
        <bold>Statistical analysis</bold>
      </p>
      <p>The statistical analysis was performed using SPSS 13.0 software (SPSS Inc, Chicago, Illinois). Categorical data were presented as frequencies (%) and compared by chi-square test. Continuous variables were presented as mean &#177; standard deviation (SD) and compared using the Student t-test or Mann-Whitney U-test when appropriate. Clinical outcomes were calculated by chi-square. The time to occurrence of death, MI, thrombosis and revascularization in the 2 groups are presented as Kaplan-Meier curves and compared using the log-rank test. Significant baseline characteristics predictive of death and TLR were identified using Cox multivariate analyses, selecting variables by the Backward Wald method. For all analyses, a 2-sided p value of &lt; .05 was considered as significant.</p>
      <p>
        <bold>Results</bold>
      </p>
      <p>The mean clinical follow-up was 22.6 &#177; 13.0 months, ranging from 6.0 to 63.5 months and was available in 98.2% of patients. There were 181 females and 323 males. The mean age of the study population was 63.7 &#177; 11.0 years, ranging from 30 to 90 years. The mean serum creatinine and GFR levels were 1.22 mg/dl and 69.8 ml/min/1.73 m&#178;, respectively.</p>
      <p>Of 504 patients included in this analysis, 339 (67.3%) presented GFR <underline>&gt;</underline> 60 ml/min/1.73 m&#178;, and 165 (32.7%) presented GFR &lt; 60 ml/min/1.73 m&#178;. Ten patients had end-stage renal disease on dialysis. The average serum creatinine of the groups was 0.95 &#177; 0.17 mg/dl and 1.76 &#177; 1.38 mg/dl, respectively. </p>
      <p>The clinical features of both groups are shown in <xref ref-type="table" rid="tab01-body2">Table 1</xref>. Patients with CKD, compared to non-CKD patients, were significantly older (68.6 &#177; 10 years vs 61.2 &#177; 9 years, p &lt; 0.001), more likely to be female (50.3% vs 28.9%, p &lt; 0.001), had hypertension (88.8% vs 72.8%, p &lt; 0.001), diabetes (47.5% vs 31.5%, p = 0.001), and were less likely to use aspirin (74.5% vs 87.4%, p &lt; 0.001), or to be currently smokers (5.7% vs 10%, p = 0.02).</p>
      <table-wrap id="tab01-body2">
        <graphic xlink:href="1678-4170-abc-96-05-0346-00045-gt01-en.jpg"/></table-wrap>
      <p>Angiographic and procedural characteristics of the two groups are presented in <xref ref-type="table" rid="tab02-body2">Table 2</xref>. The angiographic success rate was high and similar in both groups. Compared to non-CKD patients, those with CKD were more likely to undergo direct stenting (26.6% vs 35.7%, p = 0.05). By quantitative coronary angiography, minimal luminal diameter tended to be larger at baseline (0.9 &#177; 0.72 mm vs 1.0 &#177; 0.42 mm, p = 0.06) and after stenting (2.7 &#177; 0.48 mm vs 2.8 &#177; 0.49 mm, p = 0.05) in CKD patients, but the acute gain was similar. Other lesion characteristics were similar between groups.</p>
      <table-wrap id="tab02-body2">
        <graphic xlink:href="1678-4170-abc-96-05-0346-00045-gt02-en.jpg"/></table-wrap>
      <p>The incidence of adverse cardiovascular events during hospitalization was higher in CKD patients. Patients with CKD had reduced clinical success (92.1% vs 98.2%, p = 0.001), with increased rates of MI (3.7% vs 0.6%, p = 0.01) and death (3.7% vs 0.3%, p = 0.003). No patient present stroke during hospitalization. </p>
      <p>Long-term clinical outcomes are presented in <xref ref-type="table" rid="tab03-body2">Table 3</xref>. Kaplan-Meier survival analysis for death, myocardial infarction, target lesion revascularization and definite stent thrombosis are presented in <xref ref-type="fig" rid="fig01-body2">Figure 1</xref>. Patients with CKD presented higher incidence of death and cardiac death (12.3% vs 2.4%, p &lt; 0.001, and 6.1% vs 1.2%, p = 0.002, respectively), when compared to non-CKD patients. The incidence of MI was also higher in CKD patients (7.4% vs 3.3%, p = 0.04). However, the TVR and TLR rates were similar between groups (12.5%, vs 11.3%, p = 0.7, and 4.8% vs 5.6%, p = 0.7, respectively CKD and non-CKD patients). The rate of definite stent thrombosis was similar in both groups (1.9% vs 1.2%, p = 0.21, respectively CKD and non-CKD patients).</p>
      <table-wrap id="tab03-body2">
        <graphic xlink:href="1678-4170-abc-96-05-0346-00045-gt03-en.jpg"/></table-wrap>
      <fig id="fig01-body2">
        <graphic xlink:href="1678-4170-abc-96-05-0346-00045-gf01-en.jpg"/></fig>
      <p>To determine whether CKD was an independent predictor of TLR and death after DES, we performed backward multivariable analysis using the Cox proportional hazards model. Variables considered for the model included CKD, age, gender, diabetes mellitus, current smoking, hypertension, hypercholesterolemia, lesion length, minimal luminal diameter, number of vessels with coronary artery disease. Lesion length (HR 1.06; 95% CI 1.007 - 1.070, p = 0.02) was the only independent predictor of subsequent target lesion revascularization. Independent predictors of death were CKD (HR 6.93; 95% CI 2.4 - 19.5, p &lt; 0.001), current smoking (HR 3.66; 95% CI 1.20 - 11.10, p = 0.02) and diabetes (HR 2.66; 95% CI 1.03 - 6.60, p = 0.045). </p>
      <p>
        <bold>Discussion</bold>
      </p>
      <p>This is a registry of consecutive patients from two centers who underwent PCI with DES, with no exclusion criteria, and therefore represents the "real-world" practice. To the best of our knowledge, the present study has the longest follow-up of patients with CKD after DES implantation.</p>
      <p>The major finding of this study is that, although CKD patients present higher incidence of death, MI and MACE compared to patients with preserved renal function, there is no association between the presence of CKD and the risk of revascularization after DES implantation. This demonstrates that the use of DES remains as effective in CKD as in non-CKD patients for up to five years. </p>
      <p>Patients with CKD have accelerated atherosclerosis, higher incidence of CAD risk factors and more severe CAD<sup>16</sup>. Several previous studies found that mild-to-moderate CKD is associated with increased rates of death from any cause and cardiovascular death<sup>17-19</sup>. After PCI, mortality has been found to be directly related to the severity of CKD. Moreover, moderate CKD increases the risk of contrast-induced nephropathy, recurrent MI, heart failure and arrhythmias<sup>18-21</sup>. Our study found an increased prevalence of diabetes, hypertension, and older age associated with increased mortality among CKD patients. Multivariate analysis confirmed CKD, current smoking, and diabetes as independent predictors of all-cause mortality. </p>
      <p>Previous studies comparing CKD and non-CKD patients undergoing PCI with DES, found that mortality is uniformly higher in CKD patients<sup>22-24</sup>. In addition, patients with CKD have increased mortality regardless of the use of DES or BMS<sup>22,23,25</sup>. Only one study reported a lower mortality rate in CKD patients undergoing PCI with DES at 1 year<sup>25</sup>. </p>
      <p>We found that MACE was higher in CKD patients, primarily because of higher rates of mortality and MI. This finding differed from study by Nakazawa, where the higher incidence of MACE following DES implantation in CKD patients was mainly due to an increased incidence of TVR<sup>24</sup>. In that study, routine angiographic follow-up was performed at 8 months post-stenting and might have contributed to an increase in the revascularization rate.</p>
      <p>Few studies have examined restenosis and revascularization rates following percutaneous coronary intervention with DES in CKD patients. Meta-analyses of large randomized trials were not able to address this issue, given the fact that most studies excluded patients with renal failure<sup>26</sup>. Likewise, larger network meta-analyses preclude subgroup analysis due to the lack of individual patient data<sup>27</sup>. </p>
      <p>In our study, the TLR rate was low regardless of the renal function. This finding is similar to other studies on patients with moderate CKD that reported decreased incidence of revascularization after DES implantation as compared to BMS<sup>22,23,25</sup>. A sub-analysis of the TAXUS-IV Trial<sup>25</sup>, of patients with baseline moderate renal failure (GFR &lt; 60 ml/min) randomized to paclitaxel-eluting stent (n = 123) or BMS (n = 100) demonstrated significantly lower TLR (3.3% vs 12.2%, p = 0.01) and TVR rates (6.6% vs 15.2%, p = 0.04). On the other hand, one small case-control study including CKD patients presented similar rates of revascularization with DES or BMS<sup>28</sup>. </p>
      <p>Kuchulakanti et al<sup>29</sup>, in a study involving 76 patients with CKD and 1,466 controls reported low revascularization rates after DES implantation in both groups. The TVR rate at 6 months was significantly higher in CKD than in non-CKD patients (7% vs 4%, p &lt; 0.001)<sup>23</sup>. Another study evaluating revascularization involved patients who were divided in 3 groups: GFR <underline>&gt;</underline> 60 ml/min; GFR &lt; 60ml/min and patients on hemodialysis. Angiographic follow-up was performed at 8 months. After DES implantation, the TVR rate was significantly increased in hemodialysis patients in comparison to moderate CKD patients and patients without CKD (32.3%, 13% and 9.8%, p = 0.002 respectively)<sup>24</sup>.</p>
      <p>CKD has been shown to be an independent risk factor for stent thrombosis after DES implantation in some<sup>29,30</sup> ,but not all studies<sup>31</sup>. In our study, we found that the incidence of stent thrombosis was not significantly increased in CKD patients. It is conceivable that the lack of significance observed in our study was related to the reduced statistical power to assess this low-incidence event.</p>
      <p>A recently published study, although limited to US patients and not exclusively DES procedures with 1 year of follow-up presented similar results to our study. Patients with CKD had higher incidence of death and MI and TLR and stent thrombosis rates were not influenced by the presence of CKD<sup>32</sup>.</p>
      <p>
        <bold>Study limitations</bold>
      </p>
      <p>The findings of this study have to be interpreted in light of some limitations. The number of patients with end-stage renal disease on hemodialysis was very small and thus, no conclusions can be drawn regarding the safety and efficacy of DES in this population. In addition, the lack of a control group of bare metal stent does not allow us to compare the results between DES and BMS. Finally, as patients did not undergo mandatory follow-up with stress test or coronary angiography, silent ischemia and restenosis could have been underdiagnosed.</p>
      <p>
        <bold>Conclusion</bold>
      </p>
      <p>In this real-world registry, PCI with DES in CKD patients was associated with similar rates of target lesion revascularization, as compared to non-CKD patients, indicating that DES preserve the beneficial effect in preventing in-stent restenosis in this high-risk population. Nevertheless, CKD was associated with higher MI and mortality rates, demonstrating that clinical outcomes in patients with CKD, even after successful percutaneous coronary intervention, depend on the interplay of other comorbidities.</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">Impacto de la insuficiencia renal cr&#243;nica en la eficacia de Stents farmacol&#243;gicos: estudio de seguimiento de largo plazo</article-title>
      </title-group>
      <abstract xml:lang="es">
        <p>FUNDAMENTO: Pacientes con Insuficiencia Renal Cr&#243;nica (IRC) sometidos a angioplastia coronaria presentan mayores tasas de revascularizaci&#243;n de la lesi&#243;n blanco (RLB) y mortalidad. Los stents farmacol&#243;gicos (SF) est&#225;n asociados con tasas menores de reestenosis, cuando son comparados a los stents no farmacol&#243;gicos (SNF), aunque en pacientes con IRC los datos de la eficacia y seguridad del SF sean limitados. OBJETIVO: Buscamos evaluar la seguridad y eficacia de los SF en pacientes con IRC significativa, cuando fueron comparados a pacientes con funci&#243;n renal normal en un registro de la "vida real". M&#201;TODOS: 504 pacientes sometidos a intervenci&#243;n coronaria percut&#225;nea con SF en dos centros fueron incluidos. Los desenlaces fueron estratificados basados en la presencia de IRC, definida como tasa de filtraci&#243;n glomerular basal &lt; 60 ml/min/1,73 m&#178;. RESULTADOS: El control medio fue de 22,7 meses. La IRC estaba presente en 165 pacientes (32,7%). Pacientes con IRC eran de m&#225;s edad, ten&#237;an m&#225;s hipertensi&#243;n y diabetes. Pacientes con IRC presentaron mayor incidencia de muerte (12,3% vs 2,4%, p &lt; 0,001) e infarto de miocardio (IM) (7,4% vs 3,3%, p = 0,04), cuando fueron comparados a los pacientes sin IRC. Tasas de RLB fueron similares entre los grupos (4.8% vs 5.6%, p = 0,7, pacientes con y sin IRC, respectivamente). Predictores independientes de muerte fueron la IRC (HR 6,93; 2,4 - 19,5, p &lt; 0,001), tabaquismo actual (HR 3,66; 1,20 - 11,10, p = 0,02) y diabetes (HR 2,66; 1,3 - 6,60, p = 0,045). CONCLUSI&#211;N: En este registro, la intervenci&#243;n coronaria con SF en pacientes con IRC fue asociada con RLB similar comparada a los pacientes sin IRC, demostrando la eficacia de los FS en la prevenci&#243;n de la reestenosis intra stent en esa poblaci&#243;n de pacientes. La IRC fue relacionada a un aumento significativo de las tasas de IM y mortalidad. (Arq Bras Cardiol 2011;96(5):346-352)</p>
      </abstract>
      <kwd-group xml:lang="es">
        <kwd>Insuficiencia renal cr&#243;nica</kwd>
        <kwd>stents farmacol&#243;gicos</kwd>
        <kwd>eficacia</kwd>
        <kwd>seguimientos</kwd>
      </kwd-group>
    </front-stub>
    <body>
      <p>
        <bold>ART&#205;CULO ORIGINAL</bold>
      </p>
      <p><undefined id="topo-body3"/>Impacto de la insuficiencia renal cr&#243;nica en la eficacia de <italic><bold>Stents</bold></italic> farmacol&#243;gicos: estudio de seguimiento de largo plazo</p>
      <p>
        <bold>Vitor Os&#243;rio Gomes<sup>I</sup>; Patr&#237;cia Blaya<sup>I,II</sup>; Ricardo Lasevitch<sup>I</sup>; Denise Oliveira<sup>I</sup>; Patr&#237;cia Hickmann<sup>I</sup>; Lu&#237;s Smidt<sup>I</sup>; Carisi Polanczyk<sup>II</sup>; Paulo Caramori<sup>I,II</sup></bold>
      </p>
      <p><sup>I</sup>Hospital S&#227;o Lucas da Pontif&#237;cia Universidade Cat&#243;lica do Rio Grande do Sul</p>
      <p> IIUniversidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS - Brasil</p>
      <p>Correspondencia</p>
      <p>
        <bold>RESUMEN</bold>
      </p>
      <p><bold>FUNDAMENTO:</bold> Pacientes con Insuficiencia Renal Cr&#243;nica (IRC) sometidos a angioplastia coronaria presentan mayores tasas de revascularizaci&#243;n de la lesi&#243;n blanco (RLB) y mortalidad. Los <italic>stents</italic> farmacol&#243;gicos (SF) est&#225;n asociados con tasas menores de reestenosis, cuando son comparados a los <italic>stents</italic> no farmacol&#243;gicos (SNF), aunque en pacientes con IRC los datos de la eficacia y seguridad del SF sean limitados.</p>
      <p><bold>OBJETIVO:</bold> Buscamos evaluar la seguridad y eficacia de los SF en pacientes con IRC significativa, cuando fueron comparados a pacientes con funci&#243;n renal normal en un registro de la "vida real".</p>
      <p><bold>M&#201;TODOS:</bold> 504 pacientes sometidos a intervenci&#243;n coronaria percut&#225;nea con SF en dos centros fueron incluidos. Los desenlaces fueron estratificados basados en la presencia de IRC, definida como tasa de filtraci&#243;n glomerular basal &lt; 60 ml/min/1,73 m&#178;.</p>
      <p><bold>RESULTADOS:</bold> El control medio fue de 22,7 meses. La IRC estaba presente en 165 pacientes (32,7%). Pacientes con IRC eran de m&#225;s edad, ten&#237;an m&#225;s hipertensi&#243;n y diabetes. Pacientes con IRC presentaron mayor incidencia de muerte (12,3% <italic>vs</italic> 2,4%, p &lt; 0,001) e infarto de miocardio (IM) (7,4% <italic>vs</italic> 3,3%, p = 0,04), cuando fueron comparados a los pacientes sin IRC. Tasas de RLB fueron similares entre los grupos (4.8% <italic>vs</italic> 5.6%, p = 0,7, pacientes con y sin IRC, respectivamente). Predictores independientes de muerte fueron la IRC (HR 6,93; 2,4 - 19,5, p &lt; 0,001), tabaquismo actual (HR 3,66; 1,20 - 11,10, p = 0,02) y diabetes (HR 2,66; 1,3 - 6,60, p = 0,045).</p>
      <p><bold>CONCLUSI&#211;N:</bold> En este registro, la intervenci&#243;n coronaria con SF en pacientes con IRC fue asociada con RLB similar comparada a los pacientes sin IRC, demostrando la eficacia de los FS en la prevenci&#243;n de la reestenosis intra <italic>stent</italic> en esa poblaci&#243;n de pacientes. La IRC fue relacionada a un aumento significativo de las tasas de IM y mortalidad. (Arq Bras Cardiol 2011;96(5):346-352)</p>
      <p><bold>Palabras clave:</bold> Insuficiencia renal cr&#243;nica, <italic>stents</italic> farmacol&#243;gicos, eficacia, seguimientos.</p>
      <p>
        <bold>Introducci&#243;n</bold>
      </p>
      <p>La Insuficiencia Renal Cr&#243;nica (IRC) es un importante problema de salud p&#250;blica en el mundo todo. Existe una fuerte asociaci&#243;n entre la IRC y la prevalencia de enfermedad arterial coronaria (EAC) y mortalidad<sup>1</sup>. Entre pacientes con insuficiencia renal cr&#243;nica terminal (IRCT), la mortalidad card&#237;aca es de 10 a 30 veces mayor que en la poblaci&#243;n en general. El mecanismo de esta asociaci&#243;n no es enteramente conocido, pero una mayor prevalencia de factores de riesgo tradicionales en la poblaci&#243;n, como edad avanzada, hipertensi&#243;n y diabetes, contribuye a la aterosclerosis acelerada<sup>2-4</sup>.</p>
      <p>Despu&#233;s de la intervenci&#243;n coronaria percut&#225;nea (ICP) con <italic>stents</italic> no farmacol&#243;gicos (SNF), pacientes con IRC tuvieron un aumento en la incidencia de reestenosis y eventos card&#237;acos cuando fueron comparados a pacientes sin disfunci&#243;n renal<sup>5-7</sup>. Con todo, aun considerando los resultados limitados, la ICP es una alternativa muy importante en el tratamiento de pacientes con IRC que puedan presentar un riesgo quir&#250;rgico aumentado y que presenten angina limitante, a pesar del tratamiento m&#233;dico optimizado<sup>7</sup>. </p>
      <p><italic>Stents</italic> farmacol&#243;gicos (SF) redujeron la incidencia de reestenosis y la necesidad de revascularizaci&#243;n futura cuando fueron comparados a los SNF. Hay escasez de datos sobre la seguridad y eficacia del SF en pacientes con IRC, considerando que esa poblaci&#243;n es frecuentemente excluida de grandes estudios cl&#237;nicos<sup>8-10</sup>. </p>
      <p>El objetivo de este estudio fue evaluar la eficacia y seguridad de los FS en pacientes con IRC significativa, cuando fueron comparados a pacientes con funci&#243;n renal normal en un registro de la "vida real".</p>
      <p>
        <bold>M&#233;todos</bold>
      </p>
      <p>
        <bold>Poblaci&#243;n del estudio</bold>
      </p>
      <p>La poblaci&#243;n del estudio consisti&#243; en 611 pacientes consecutivos sometidos a ICP con SF entre junio de 2002 y junio de 2006 en dos hospitales terciarios en Porto Alegre, Brasil. Un total de 504 pacientes fue incluido en este an&#225;lisis, pues los mismos ten&#237;an medidas de creatinina s&#233;ricas disponibles de hasta 30 d&#237;as antes de la intervenci&#243;n coronaria. </p>
      <p>La IRC fue definida como la tasa de filtraci&#243;n glomerular (TFG) &lt; 60 ml/min/1,73 m&#178;, un valor de corte previamente propuesto por la <italic>National Foundation's Kidney Disease Outcome Quality Initiative Advisory Board</italic> (K/DOQI), para identificar pacientes con insuficiencia renal moderada<sup>11</sup>. En conformidad, los pacientes fueron divididos en 2 grupos: 1) pacientes con la TFG <underline>&gt;</underline> 60 ml/min/1,73 m&#178; y 2) pacientes con GFR &lt; 60 ml/min/1,73 m&#178;.</p>
      <p>La TFG fue calculada por la ecuaci&#243;n de la modificaci&#243;n de la dieta en la enfermedad renal (MDRD): TFG <italic>Estimada</italic> = 186 x (creatinina s&#233;rica)<sup>-1.154</sup> x (edad)<sup>- 0.203 </sup>x (0.742 si fuese del sexo femenino) x (1.210 si negro/a), donde la creatinina es medida en mg/dl, edad en a&#241;os y la TFG es expresada en ml/min/1,73 m&#178; <sup>12,13</sup>. </p>
      <p>Este estudio fue aprobado por el Comit&#233; de &#201;tica e Investigaci&#243;n Institucional local de ambos hospitales.</p>
      <p>Este estudio fue financiado por un fondo para educaci&#243;n irrestricto del Boston Scientific, Cordis Corporation y Medtronic. Estas empresas no tuvieron acceso a los datos y no tienen el derecho a revisar el art&#237;culo antes de su publicaci&#243;n.</p>
      <p>
        <bold>Definiciones de <italic>endpoints</italic> y control cl&#237;nico</bold>
      </p>
      <p>El infarto del miocardio (IM) fue definido como una elevaci&#243;n de la fracci&#243;n creatina quinasa-MB de tres veces encima del l&#237;mite de la variaci&#243;n normal<sup>14</sup>. La tasa de revascularizaci&#243;n del vaso blanco (RVB) fue definida como una revascularizaci&#243;n percut&#225;nea repetida o quir&#250;rgica del vaso tratado. La revascularizaci&#243;n de la lesi&#243;n blanco (RLB) fue definida como una revascularizaci&#243;n percut&#225;nea o quir&#250;rgica de la lesi&#243;n &#237;ndice durante el control. Un evento adverso card&#237;aco mayor (MACE) fue definido como un <italic>endpoint</italic> compuesto de muerte card&#237;aca, IM no fatal o RVB durante el control. La definici&#243;n de trombosis de <italic>stent</italic> (TS) fue basada en los criterios establecidos por el <italic>Academic Research Consortium </italic>(ARC)<sup>15</sup>.</p>
      <p>El &#233;xito angiogr&#225;fico fue definido como estenosis &lt; 20% y flujo TIMI 3 al final del procedimiento. EL &#233;xito cl&#237;nico fue definido como &#233;xito angiogr&#225;fico y la ausencia de complicaciones cl&#237;nicas como muerte, IM, revascularizaci&#243;n urgente y derrame.</p>
      <p>Para pacientes con m&#225;s de una intervenci&#243;n durante el per&#237;odo de control del estudio, solamente la primera intervenci&#243;n fue considerada para an&#225;lisis de los <italic>endpoints</italic>.</p>
      <p>El tipo de ST usado durante el procedimiento coronario fue dejado a criterio del cardi&#243;logo intervencionista.</p>
      <p>El control cl&#237;nico fue hecho a trav&#233;s de entrevistas telef&#243;nicas con el paciente, revisi&#243;n de las historias de los pacientes ambulatorios y contacto con el m&#233;dico asistente. Todos los eventos cl&#237;nicos fueron adjudicados por el an&#225;lisis de las fuentes de documentaci&#243;n por un cardi&#243;logo ciego a los otros datos cl&#237;nicos.</p>
      <p>
        <bold>An&#225;lisis angiogr&#225;fico coronario cuantitativo</bold>
      </p>
      <p>Los angiogramas coronarios basales y post procedimiento obtenidos fueron analizados por un cardi&#243;logo experimentado. La angiograf&#237;a coronaria cuantitativa <italic>off-line</italic> de la intervenci&#243;n &#237;ndice fue ejecutada usando el cat&#233;ter gu&#237;a para calibraci&#243;n de la magnificaci&#243;n de la imagen (<italic>CardioNow Websend DICOM Study Sharing Software</italic>, HeartLab, Inc., Westerly, Rhode Island). Fueron medidos el di&#225;metro luminal m&#237;nimo y di&#225;metro del vaso de referencia antes y despu&#233;s de la intervenci&#243;n a partir de corte &#250;nico mostrando el menor di&#225;metro luminal.</p>
      <p>
        <bold>An&#225;lisis estad&#237;stico</bold>
      </p>
      <p>El an&#225;lisis estad&#237;stico fue realizado con el <italic>software</italic> SPSS 13.0 (SPSS Inc, Chicago, Illinois). Datos absolutos fueron presentados como frecuencias (%) y comparados por el test Chi-cuadrado. Variables continuas fueron presentadas como media &#177; desviaci&#243;n est&#225;ndar (DE) y comparadas usando el test <italic>t</italic> de student o el test U de Mann-Whitney cuando fue apropiado. Resultados cl&#237;nicos fueron calculados por chi-quadrado. Los tiempos para ocurrencia de muerte, IM, trombosis y revascularizaci&#243;n en los 2 grupos son presentados como curvas de Kaplan-Meier y comparados usando el test log-rank. Caracter&#237;sticas basales significativos, predictivas de muerte y RLB fueron identificadas usando an&#225;lisis multivariados de Cox, seleccionando variables por el m&#233;todo Backward Wald. Para todos los an&#225;lisis, un valor de p bilateral &lt; 0,05 fue considerado para indicar diferencias significativos.</p>
      <p>
        <bold>Resultados</bold>
      </p>
      <p>La media del control cl&#237;nico fue de 22,6 &#177; 13,0 meses, con una variaci&#243;n de 6,0 a 63,5 meses y estaba disponible en 98,2% de los pacientes. Hab&#237;a 181 mujeres y 323 hombres. La media de la edad en la poblaci&#243;n de estudio era de 63,7 &#177; 11,0, variando de 30 a 90 a&#241;os de edad. La creatinina s&#233;rica media y la TFG eran 1,22 mg/dl y 69,8 ml/min/1,73 m&#178;, respectivamente. </p>
      <p>De los 504 pacientes incluidos en este an&#225;lisis, 339 (67,3%) presentaron TFG <underline>&gt;</underline> 60 ml/min/1,73 m&#178;, y 165 (32,7%) presentaron TFG &lt; 60 ml/min/1,73 m&#178;. Diez pacientes presentaban insuficiencia renal en nivel terminal en la di&#225;lisis. La creatinina s&#233;rica media de los grupos fue de 0,95 &#177; 0,17 mg/dl y 1,76 &#177; 1,38 mg/dl, respectivamente.</p>
      <p>Las caracter&#237;sticas cl&#237;nicas de ambos grupos son mostradas en la <xref ref-type="table" rid="t1-body3">Tabla 1</xref>. Pacientes con IRC, comparados a los pacientes sin IRC, eran significativamente mayores (68,6 &#177; 10 a&#241;os vs. 61,2 &#177; 9 a&#241;os, p &lt; 0,001), con mayor probabilidad de ser mujeres (50,3% <italic>vs</italic> 28,9%, p &lt; 0,001), ten&#237;an hipertensi&#243;n (88,8% <italic>vs</italic> 72,8%, p &lt; 0,001), diabetes (47.5% <italic>vs</italic> 31.5%, p = 0,001), y eran menos propensos a usar aspirina (74,5% <italic>vs</italic> 87,4%, p &lt; 0,001), o ser fumantes actuales (5,7% <italic>vs</italic> 10%, p = 0,02).</p>
      <table-wrap id="t1-body3">
        <graphic xlink:href="1678-4170-abc-96-05-0346-00045-gt01-es.jpg"/></table-wrap>
      <p>Caracter&#237;sticas angiogr&#225;ficas y de procedimiento de los dos grupos son presentadas en la <xref ref-type="table" rid="t2-body3">Tabla 2</xref>. La tasa de &#233;xito angiogr&#225;fico fue alta y similar en los dos grupos. Comparados a los pacientes sin IRC, aquellos con IRC tuvieron mayor probabilidad de ser sometidos al uso de <italic>stent</italic> direto (26,6% <italic>vs</italic> 35,7%, p = 0,05). Por la angiograf&#237;a coronaria cuantitativa, el di&#225;metro luminal m&#237;nimo tendi&#243; a ser mayor en la condici&#243;n basal (0,9 &#177; 0,72 mm <italic>vs</italic> 1,0 &#177; 0,42 mm, p = 0,06) y despu&#233;s de el <italic>stent</italic> (2,7 &#177; 0,48 mm <italic>vs</italic> 2,8 &#177; 0,49 mm, p = 0,05) en los pacientes con IRC, pero el aumento agudo fue similar. Otras caracter&#237;sticas de las lesiones fueron similares entre los grupos.</p>
      <table-wrap id="t2-body3">
        <graphic xlink:href="1678-4170-abc-96-05-0346-00045-gt02-es.jpg"/></table-wrap>
      <p>La incidencia de eventos cardiovasculares adversos durante la hospitalizaci&#243;n fue alta en pacientes con IRC. Pacientes con IRC presentaron &#233;xito cl&#237;nico reducido (92,1% <italic>vs</italic> 98,2%, p = 0,001), con aumento en las tasas de IM (3,7% <italic>vs</italic> 0,6%, p = 0,01) y muerte (3,7% <italic>vs</italic> 0,3%, p = 0,003). Ning&#250;n paciente sufri&#243; derrame durante la hospitalizaci&#243;n. </p>
      <p>Los resultados cl&#237;nicos de largo plazo son presentados en la <xref ref-type="table" rid="t3-body3">Tabla 3</xref>. Los an&#225;lisis de supervivencia de Kaplan-Meier para muerte, infarto del miocardio, revascularizaci&#243;n de la lesi&#243;n blanco, y trombosis de <italic>stent</italic> definitiva son presentados en la <xref ref-type="fig" rid="esa01f1-body3">Figura 1</xref>. Pacientes con IRC presentaron mayor incidencia de muerte y muerte card&#237;aca (12,3% <italic>vs</italic> 2,4%, p &lt; 0,001, y 6,1% <italic>vs</italic> 1,2%, p = 0,002, respectivamente) cuando fueron comparados con pacientes sin IRC. La incidencia de IM tambi&#233;n fue alta en pacientes con IRC (7,4% <italic>vs</italic> 3,3%, p = 0,04). Con todo, las tasas de RVB y RLB fueron similares entre los grupos (12,5%, <italic>vs</italic> 11,3%, p = 0,7, y 4,8% <italic>vs</italic> 5,6%, p = 0,7, respectivamente pacientes con IRC y sin IRC). La tasa de trombosis de <italic>stent</italic> definitiva fue similar en los dos grupos (1,9% <italic>vs</italic> 1,2%, p = 0,21, pacientes con IRC y sin IRC, respectivamente).</p>
      <p content-type="asset">
        <fig id="esa01f1-body3">
          <graphic xlink:href="1678-4170-abc-96-05-0346-00045-gf01-es.jpg"/></fig>
      </p>
      <table-wrap id="t3-body3">
        <graphic xlink:href="1678-4170-abc-96-05-0346-00045-gt03-es.jpg"/></table-wrap>
      <p>Para determinar si la IRC era un predictor independiente de RLB y muerte despu&#233;s de SF, nosotros ejecutamos an&#225;lisis multivariado <italic>backward</italic> usando el modelo de riesgos proporcionales de Cox. Variables consideradas para el modelo incluyen IRC, edad, sexo, diabetes mellitus, tabaquismo actual, hipertensi&#243;n, hipercolesterolemia, largo de la lesi&#243;n, di&#225;metro luminal m&#237;nimo, n&#250;mero de vasos con enfermedad arterial coronaria. El largo de lesi&#243;n (HR 1,06; IC95% 1,007 - 1,070, p = 0,02) fue el &#250;nico predictor independiente de la revascularizaci&#243;n de la lesi&#243;n blanco subsecuente. Predictores independientes de muerte fueron IRC (HR 6,93; IC95% 2,4 - 19.5, p &lt; 0,001), tabaquismo actual (HR 3,66; IC95% 1,20 - 11,10, p = 0,02) y diabetes (HR 2,66; IC95% 1,03 - 6,60, p = 0,045).</p>
      <p>
        <bold>Discusi&#243;n</bold>
      </p>
      <p>Este es un registro de pacientes consecutivos de dos centros que fueron sometidos a ICP con SF, sin criterios de exclusi&#243;n y que, por lo tanto, representa la pr&#225;ctica del "mundo real". Hasta donde sabemos, el presente estudio tiene el m&#225;s largo per&#237;odo de control de pacientes con IRC despu&#233;s de la implantaci&#243;n del SF.</p>
      <p>El principal hallazgo de este estudio es que, aunque los pacientes con IRC hayan presentado mayor incidencia de muerte, IM y MACE comparados con pacientes con funciones renales preservadas, no hay asociaci&#243;n entre la presencia de IRC y el riesgo de revascularizaci&#243;n despu&#233;s de la implantaci&#243;n del SF. Esto demuestra que el uso del SF permanece tan efectivo en pacientes con IRC como en pacientes sin IRC por hasta cinco a&#241;os. </p>
      <p>Pacientes con IRC presentan aterosclerosis acelerada, mayor incidencia de factores de riesgo de EAC y EAC m&#225;s grave<sup>16</sup>. Diversos estudios anteriores observaron que una IRC media a moderada est&#225; asociada con tasas mayores de muerte por cualquier causa y muerte cardiovascular<sup>17-19</sup>. Despu&#233;s de la ICP, fue observado que la mortalidad est&#225; directamente relacionada a la gravedad de la IRC. Adem&#225;s de eso, una IRC moderada aumenta el riesgo de nefropat&#237;a inducida por contraste, IM recurrente, insuficiencia card&#237;aca y arritmias<sup>18-21</sup>. Nuestro estudio encontr&#243; un aumento en la prevalencia de diabetes, hipertensi&#243;n y edad avanzada asociados a un aumento de la mortalidad entre los pacientes con IRC. El an&#225;lisis multivariado confirm&#243; la IRC, tabaquismo actual y diabetes como predictores independientes de mortalidad por todas las causas.</p>
      <p>Estudios anteriores comparando pacientes con IRC y pacientes sin IRC sometidos a ICP con SF, observaron que la mortalidad es uniformemente mayor en pacientes con IRC<sup>22-24</sup>. Adem&#225;s de eso, pacientes con IRC presentaron un aumento de la mortalidad a pesar del uso de SF o SNF<sup>22,23,25</sup>. Solamente un estudio relat&#243; una tasa de mortalidad menor en pacientes con IRC sometidos a ICP con SF despu&#233;s de 1 a&#241;o<sup>25</sup>.</p>
      <p>Encontramos una mayor incidencia de MACE en pacientes con IRC, primariamente debido a las altas tasas de mortalidad y IM. Ese hallazgo difiere del estudio Nakazawa, donde la mayor incidencia de MACE despu&#233;s de la implantaci&#243;n del SF en pacientes con IRC ocurr&#237;a principalmente debido a la mayor incidencia de RVA<sup>24</sup>. En aquel estudio, el control angiogr&#225;fico de rutina fue ejecutado ocho meses despu&#233;s del <italic>stenting</italic> y puede haber contribuido a un aumento en la tasa de revascularizaci&#243;n. </p>
      <p>Pocos estudios evaluaron las tasas de reestenosis y revascularizaci&#243;n despu&#233;s de la intervenci&#243;n coronaria percut&#225;nea con SF en pacientes con IRC. Metan&#225;lisis de grandes estudios cl&#237;nicos randomizados no fueron capaces de evaluar esa cuesti&#243;n, considerando que la mayor parte de los estudios excluy&#243; los pacientes con insuficiencia renal<sup>26</sup>. De la misma forma, metan&#225;lisis de redes mayores impiden an&#225;lisis de subgrupos debido a la falta de datos individuales de los pacientes<sup>27</sup>.</p>
      <p>En nuestro estudio, la tasa de RLB fue baja, independientemente de la funci&#243;n renal. Ese hallazgo es similar al de otros estudios en pacientes con IRC moderada, que relataron una disminuci&#243;n en la incidencia de revascularizaci&#243;n despu&#233;s de la implantaci&#243;n del SF cuando fueron comparados al SNF<sup>22,23,25</sup>. Un sub-an&#225;lisis del estudio TAXUS-IV<sup>25</sup>, de pacientes con insuficiencia renal moderada basal (TFG &lt; 60 ml/min), randomizados para el <italic>stent</italic> eluidor de paclitaxel (n = 123) o SNF (n = 100), demostr&#243; tasas significativamente menores de RLB (3,3% <italic>vs</italic> 12,2%, p = 0,01) y RVB (6,6% <italic>vs</italic> 15,2%, p = 0,04). Por otro lado, un peque&#241;o estudio de caso control incluyendo pacientes con IRC present&#243; tasas similares de revascularizaci&#243;n con SF o SNF<sup>28</sup>.</p>
      <p>Kuchulakanti et al<sup>29</sup>, en un estudio incluyendo 76 pacientes con IRC y 1.466 controles, relataron bajas tasas de revascularizaci&#243;n despu&#233;s de la implantaci&#243;n del SF en los dos grupos. La tasa de RVB en seis meses fue significativamente mayor en los pacientes con IRC del que en los pacientes sin IRC (7% <italic>vs</italic> 4%, p &lt; 0,001)<sup>23</sup>. Otro estudio evaluando la revascularizaci&#243;n incluy&#243; pacientes que fueron divididos en tres grupos: TFG <underline>&gt;</underline> 60 ml/min; TFG &lt; 60 ml/min y pacientes en hemodi&#225;lisis. El control angiogr&#225;fico fue realizado a los ocho meses. Despu&#233;s de la implantaci&#243;n del SF, la tasa de RVB aument&#243; significativamente en pacientes en hemodi&#225;lisis, cuando fueron comparado a pacientes con IRC moderada y pacientes sin IRC (32,3%, 13% y 9,8%, p = 0,002 respectivamente)<sup>24</sup>.</p>
      <p>Ha sido demostrado que la IRC es un factor de riesgo independiente para la trombosis de <italic>stent</italic> despu&#233;s de la implantaci&#243;n de SF en algunos<sup>29,30</sup>, pero no en todos los estudios<sup>31</sup>. En nuestro estudio, observamos que la incidencia de trombosis de <italic>stent</italic> no estaba significativamente aumentada en pacientes con IRC. Es posible que la falta de significaci&#243;n observada en nuestro estudio est&#233; relacionada al reducido poder estad&#237;stico para evaluar ese evento de baja incidencia.</p>
      <p>Un art&#237;culo recientemente publicado, aunque limitado a pacientes de los EUA y no exclusivamente a procedimientos de SF, con 1 a&#241;o de control cl&#237;nico, present&#243; resultados similares a los de nuestro estudio. Pacientes con IRC presentaron mayor incidencia de muerte y IM, y tasas de RLB y trombosis de <italic>stent</italic> no fueron influenciados por la presencia de la IRC<sup>32</sup>.</p>
      <p>
        <bold>Limitaciones del estudio</bold>
      </p>
      <p>Los hallazgos de este estudio deben ser interpretados bajo la luz de algunas limitaciones. El n&#250;mero de pacientes con enfermedad renal terminal en hemodi&#225;lisis era muy peque&#241;o, y por lo tanto ninguna conclusi&#243;n puede ser extra&#237;da, a pesar de la seguridad y eficacia del SF en esa poblaci&#243;n. Adem&#225;s de eso, la falta de un grupo de control de <italic>stent</italic> no farmacol&#243;gico no nos permiti&#243; comparar resultados entre SF y SNF. </p>
      <p>Finalmente, como los pacientes no fueron sometidos a seguimiento obligatorio con test de esfuerzo o angiografia coronaria, isquemia silenciosa y reestenosis pueden haber sido subdiagnosticadas.</p>
      <p>
        <bold>Conclusi&#243;n</bold>
      </p>
      <p>En ese registro de "mundo real", la ICP con SF en pacientes con IRC estuvo asociada con revascularizaci&#243;n de lesi&#243;n blanco, cuando fueron comparados con pacientes sin IRC, indicando que el SF preserva el efecto ben&#233;fico en la prevenci&#243;n de reestenosis intra <italic>stent</italic> en esa poblaci&#243;n de alto riesgo. De cualquier forma, la IRC estaba asociada con tasas m&#225;s altas de IM y mortalidad, demostrando que desenlaces cl&#237;nicos en pacientes con IRC, aun despu&#233;s de ICP exitosa, dependen de la interrelaci&#243;n de otras comorbilidades.</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>Este art&#237;culo forma parte de Disertaci&#243;n de Maestr&#237;a de Patr&#237;cia Blaya, por el Hospital S&#227;o Lucas - PUCRS.</p>
      <p>
        <bold>Referencias</bold>
      </p>
    </body>
  </sub-article>
</article>
