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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">Y5RpXSQDssw7fpJf7fTJwhh</article-id>
      <article-id pub-id-type="other">00006</article-id>
      <article-id pub-id-type="publisher-id" specific-use="scielo-v2">S0066-782X2006001700006</article-id>
      <article-id pub-id-type="publisher-id" specific-use="scielo-v1">S0066-782X(06)08700406</article-id>
      <article-id pub-id-type="doi">10.1590/S0066-782X2006001700006</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Artigos Originais</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Preditores independentes de resultados intra-hospitalares p&#243;s-implante de stent coronariano</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Neri-Souza</surname>
            <given-names>Ant&#244;nio Jos&#233;</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Aguiar</surname>
            <given-names>Bruno Machado</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Coelho</surname>
            <given-names>Andr&#233; Borges</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Nascimento</surname>
            <given-names>Anderson Jorge Lima</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Oliveira J&#250;nior</surname>
            <given-names>Waldemar Souza</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Godinho</surname>
            <given-names>Antonio Gilson Lapa</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Ramos</surname>
            <given-names>Nilson Borges</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Rabelo J&#250;nior</surname>
            <given-names>&#193;lvaro</given-names>
          </name>
          <xref ref-type="aff" rid="aff01"/>
        </contrib>
      </contrib-group>
      <aff id="aff01">
        <addr-line>
          <named-content content-type="city">Salvador</named-content>
          <named-content content-type="state">BA</named-content>
        </addr-line>
        <institution content-type="orgname">Universidade Federal da Bahia</institution>
        <institution content-type="orgdiv1">Funda&#231;&#227;o Bahiana de Cardiologia </institution>
      </aff>
      <pub-date date-type="collection" publication-format="electronic">
        <month>10</month>
        <year>2006</year>
      </pub-date>
      <volume>87</volume>
      <issue>4</issue>
      <fpage>429</fpage>
      <lpage>438</lpage>
      <history>
        <date date-type="received">
          <day>27</day>
          <month>03</month>
          <year>2005</year>
        </date>
        <date date-type="accepted">
          <day>11</day>
          <month>11</month>
          <year>2005</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>OBJETIVO: Identificar preditores cl&#237;nicos e angiogr&#225;ficos independentes, determinantes de resultados imediatos p&#243;s-implante de stent coron&#225;rio. M&#201;TODOS: Novecentos e quarenta e seis pacientes com idade m&#233;dia de 61,04 &#177; 10,98 anos (31 a 91 anos), foram submetidos a implante de stents, sendo 580 do sexo masculino (61,3%). Sucesso do procedimento foi definido quando pelo menos um vaso era dilatado com sucesso, com estenose residual &lt; 20%. Sucesso cl&#237;nico ocorreu quando se obteve &#234;xito no procedimento na aus&#234;ncia de complica&#231;&#245;es maiores (IAM, necessidade de RM ou &#243;bito) na fase intra-hospitalar. Caracter&#237;sticas cl&#237;nicas e angiogr&#225;ficas foram analisadas. Todas as vari&#225;veis relacionadas aos resultados imediatos pela an&#225;lise univariada foram inclu&#237;das no modelo de regress&#227;o log&#237;stica. RESULTADOS: Sucesso do procedimento foi obtido em 98,9%, sucesso cl&#237;nico em 95,7%, insucesso n&#227;o-complicado em 0,1% e complica&#231;&#245;es maiores em 4,2%. A an&#225;lise multivariada evidenciou que les&#227;o resten&#243;tica, calcifica&#231;&#227;o e contorno irregular se relacionaram com sucesso do procedimento; diabetes mellitus, choque cardiog&#234;nico, s&#237;ndromes coron&#225;rias agudas, idade, disfun&#231;&#227;o ventricular esquerda, calcifica&#231;&#227;o e oclus&#227;o total foram preditores de sucesso cl&#237;nico. Diabetes mellitus, choque cardiog&#234;nico, s&#237;ndromes coron&#225;rias agudas, idade, doen&#231;a multiarterial, disfun&#231;&#227;o ventricular esquerda, calcifica&#231;&#227;o, les&#245;es longas e oclus&#227;o total foram preditores de complica&#231;&#245;es maiores; enquanto que choque cardiog&#234;nico, s&#237;ndromes coron&#225;rias agudas, idade, hipertens&#227;o arterial sist&#234;mica e disfun&#231;&#227;o ventricular esquerda foram preditores de mortalidade intra-hospitalar. CONCLUS&#195;O: Nossos resultados sugerem que os resultados imediatos p&#243;s-implante de stents foram significativamente relacionados com choque cardiog&#234;nico, disfun&#231;&#227;o ventricular esquerda, idade, calcifica&#231;&#227;o e oclus&#227;o total.</p>
      </abstract>
      <kwd-group xml:lang="pt" kwd-group-type="author-generated">
        <kwd>Stent</kwd>
        <kwd>fatores de risco</kwd>
        <kwd>an&#225;lise multivariada</kwd>
        <kwd>arteriosclerose coron&#225;ria</kwd>
        <kwd>angina pectoris</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>ARTIGO ORIGINAL</bold>
    </p>
    <p>
      <bold>Preditores independentes de resultados intra-hospitalares p&#243;s-implante de <italic>stent</italic> coronariano</bold>
    </p>
    <p>
      <bold>Ant&#244;nio Jos&#233; Neri-Souza; Bruno Machado Aguiar; Andr&#233; Borges Coelho; Anderson Jorge Lima Nascimento; Waldemar Souza Oliveira J&#250;nior; Antonio Gilson Lapa Godinho; Nilson Borges Ramos; &#193;lvaro Rabelo J&#250;nior</bold>
    </p>
    <p>Funda&#231;&#227;o Bahiana de Cardiologia, Universidade Federal da Bahia - Salvador, BA</p>
    <p>
      <xref ref-type="corresp" rid="back">Correspond&#234;ncia</xref>
    </p>
    <p>
      <bold>RESUMO</bold>
    </p>
    <p><bold>OBJETIVO:</bold> Identificar preditores cl&#237;nicos e angiogr&#225;ficos independentes, determinantes de resultados imediatos p&#243;s-implante de <italic>stent</italic> coron&#225;rio. </p>
    <p><bold>M&#201;TODOS:</bold> Novecentos e quarenta e seis pacientes com idade m&#233;dia de 61,04 &#177; 10,98 anos (31 a 91 anos), foram submetidos a implante de <italic>stents</italic>, sendo 580 do sexo masculino (61,3%). Sucesso do procedimento foi definido quando pelo menos um vaso era dilatado com sucesso, com estenose residual &lt; 20%. Sucesso cl&#237;nico ocorreu quando se obteve &#234;xito no procedimento na aus&#234;ncia de complica&#231;&#245;es maiores (IAM, necessidade de RM ou &#243;bito) na fase intra-hospitalar. Caracter&#237;sticas cl&#237;nicas e angiogr&#225;ficas foram analisadas. Todas as vari&#225;veis relacionadas aos resultados imediatos pela an&#225;lise univariada foram inclu&#237;das no modelo de regress&#227;o log&#237;stica. </p>
    <p><bold>RESULTADOS:</bold> Sucesso do procedimento foi obtido em 98,9%, sucesso cl&#237;nico em 95,7%, insucesso n&#227;o-complicado em 0,1% e complica&#231;&#245;es maiores em 4,2%. A an&#225;lise multivariada evidenciou que les&#227;o resten&#243;tica, calcifica&#231;&#227;o e contorno irregular se relacionaram com sucesso do procedimento; diabetes mellitus, choque cardiog&#234;nico, s&#237;ndromes coron&#225;rias agudas, idade, disfun&#231;&#227;o ventricular esquerda, calcifica&#231;&#227;o e oclus&#227;o total foram preditores de sucesso cl&#237;nico. Diabetes mellitus, choque cardiog&#234;nico, s&#237;ndromes coron&#225;rias agudas, idade, doen&#231;a multiarterial, disfun&#231;&#227;o ventricular esquerda, calcifica&#231;&#227;o, les&#245;es longas e oclus&#227;o total foram preditores de complica&#231;&#245;es maiores; enquanto que choque cardiog&#234;nico, s&#237;ndromes coron&#225;rias agudas, idade, hipertens&#227;o arterial sist&#234;mica e disfun&#231;&#227;o ventricular esquerda foram preditores de mortalidade intra-hospitalar. </p>
    <p><bold>CONCLUS&#195;O:</bold> Nossos resultados sugerem que os resultados imediatos p&#243;s-implante de <italic>stents</italic> foram significativamente relacionados com choque cardiog&#234;nico, disfun&#231;&#227;o ventricular esquerda, idade, calcifica&#231;&#227;o e oclus&#227;o total.</p>
    <p><bold>Palavras-chave:</bold><italic>Stent</italic>, fatores de risco, an&#225;lise multivariada, arteriosclerose coron&#225;ria, angina pectoris.</p>
    <p>A introdu&#231;&#227;o da angioplastia transluminal coron&#225;ria percut&#226;nea por Gr&#252;ntzig<sup>1</sup> em 1977, representou um marco no tratamento da doen&#231;a arterial coron&#225;ria (DAC), tendo suas indica&#231;&#245;es, desde ent&#227;o, expandido de forma extraordin&#225;ria. V&#225;rios fatores contribu&#237;ram para aumentar os &#237;ndices de sucesso e reduzir o n&#250;mero de complica&#231;&#245;es, al&#233;m de aumentar as indica&#231;&#245;es do procedimento, tais como, maior experi&#234;ncia do operador e evolu&#231;&#227;o tecnol&#243;gica representada pelo uso de <italic>stents</italic> e de inibidores de glicoprote&#237;na plaquet&#225;ria IIb/IIIa<sup>2-4</sup>.</p>
    <p>Ao mesmo tempo, caracter&#237;sticas cl&#237;nicas, angiogr&#225;ficas e relacionadas ao procedimento t&#234;m sido identificadas como determinantes de resultados imediatos. Com base nessas observa&#231;&#245;es, a <italic>American College of Cardiology</italic> e a <italic>American Heart Association</italic> idealizaram uma classifica&#231;&#227;o de acordo com crit&#233;rios angiogr&#225;ficos, para estimar a probabilidade de sucesso imediato e ocorr&#234;ncia de complica&#231;&#245;es<sup>5-6</sup>.</p>
    <p>V&#225;rios estudos t&#234;m buscado identificar preditores de resultados intra-hospitalares p&#243;s-implante de <italic>stent</italic>, sendo que alguns autores desenvolveram modelos de predi&#231;&#227;o de eventos intra-hospitalares<sup>7-21</sup>. Estimativas de risco s&#227;o importantes para avalia&#231;&#227;o dos resultados, al&#233;m de auxiliar o paciente e seus familiares no processo de consentimento para a realiza&#231;&#227;o do procedimento. &#201; importante tamb&#233;m para ajudar o m&#233;dico a selecionar ou evitar determinada estrat&#233;gia ou medicamento durante o procedimento.</p>
    <p>Nosso objetivo &#233; analisar os resultados intra-hospitalares de pacientes tratados com implante de <italic>stent,</italic> identificando preditores independentes, cl&#237;nicos e angiogr&#225;ficos, relacionados a sucesso e complica&#231;&#245;es maiores.</p>
    <p>
      <bold>M&#233;todos</bold>
    </p>
    <p><italic>Pacientes</italic> - Entre outubro de 1995 e dezembro de 2002, 946 pacientes foram consecutivamente submetidos a implante de <italic>stents</italic> em 1.045 les&#245;es. Quinhentos e oitenta pacientes eram do sexo masculino (61,3%) e 366 do sexo feminino (38,7%), com idade m&#233;dia de 61,04 &#177; 10,98 (31 a 91) anos. Diabetes mellitus estava presente em 243 pacientes (25,7%), hipertens&#227;o arterial sist&#234;mica, em 677 pacientes (71,6%), dislipidemia em 694 pacientes (73,4%) e 291 pacientes eram tabagistas (25,5%). Duzentos e cinq&#252;enta e nove pacientes tinham hist&#243;ria pr&#233;via de infarto (27,4%), 86 de cirurgia de revasculariza&#231;&#227;o do mioc&#225;rdio (9,1%) e 47 de interven&#231;&#227;o coron&#225;ria percut&#226;nea pr&#233;via no vaso tratado, sendo, portanto, uma les&#227;o resten&#243;tica (5,0%). Quatrocentos e sessenta e seis pacientes eram multiarteriais (49,3%) e 273 apresentavam disfun&#231;&#227;o ventricular esquerda moderada a severa (28,9%). Antes da interven&#231;&#227;o, 420 pacientes apresentavam angina est&#225;vel (44,4%), 344 angina inst&#225;vel (36,4%) e, 182, infarto agudo do mioc&#225;rdio (19,2%), sendo que 22 dos pacientes com IAM se encontravam em choque cardiog&#234;nico (2,2%). As caracter&#237;sticas cl&#237;nicas est&#227;o sumarizadas na <xref ref-type="table" rid="tabela1">tabela 1</xref>.</p>
    <table-wrap id="tabela1">
      <graphic xlink:href="1678-4170-abc-87-04-0429-00006-gt01.jpg"/></table-wrap>
    <p><italic>Les&#227;o -</italic> Foram tratadas 1045 les&#245;es (1,11 les&#227;o/paciente), sendo 536 na descendente anterior (51,2%), 313 na coron&#225;ria direita (30,0%), 157 na circunflexa (15,0%), 8 em tronco da coron&#225;ria esquerda (0,8%), 25 em enxertos de pontes de veia safena (2,4%) e 6 em anastomose da art&#233;ria mam&#225;ria interna esquerda para descendente anterior (0,6%). Trinta e cinco les&#245;es (3,4%) envolviam angula&#231;&#227;o maior ou igual a 45&#186;, 145 les&#245;es em bifurca&#231;&#227;o (13,9%), 130 les&#245;es calcificadas (12,4%), 402 com contorno irregular (38,5%), 286 les&#245;es com extens&#227;o maior ou igual a 10 mm (27,4%), 127 oclus&#245;es totais (12,2%), 33 les&#245;es ostiais (3,2%), 32 les&#245;es com tortuosidade moderada a severa no segmento proximal (3,1%) e 223 les&#245;es com trombo (21,3%). Setecentas e cinq&#252;enta e sete les&#245;es eram do tipo B2 e C, consideradas les&#245;es complexas (72,4%). As caracter&#237;sticas angiogr&#225;ficas est&#227;o sumarizadas na <xref ref-type="table" rid="tabela2">tabela 2</xref>.</p>
    <table-wrap id="tabela2">
      <graphic xlink:href="1678-4170-abc-87-04-0429-00006-gt02.jpg"/></table-wrap>
    <p><italic>Procedimento -</italic> A t&#233;cnica de implante de <italic>stent</italic> j&#225; foi descrita previamente, sendo utilizada a t&#233;cnica femoral em 95% dos casos<sup>22</sup>. Heparina intravenosa foi administrada em bolus (5.000 a 10.000 UI) ap&#243;s a pun&#231;&#227;o da art&#233;ria femoral. Diferentes tipos de <italic>stents</italic> foram implantados sob controle fluorosc&#243;pico. A extens&#227;o e o di&#226;metro dos <italic>stents</italic> utilizados foram decididos pelos operadores. O resultado final foi baseado no controle angiogr&#225;fico. Todos os pacientes receberam aspirina (100 a 200 mg por via oral, uma vez ao dia) e ticlopidina (250 mg por via oral, duas vezes ao dia) ou clopidogrel (300 mg por via oral, dose inicial, seguido por 75 mg por via oral, uma vez ao dia), iniciados 48 horas antes do procedimento, quando clinicamente poss&#237;vel.</p>
    <p><italic>Defini&#231;&#245;es - Diabetes Mellitus -</italic> Foram considerados diab&#233;ticos os pacientes com diagn&#243;stico pr&#233;vio, em uso de medica&#231;&#245;es (hipoglicemiantes orais ou insulina), ou diagnosticado na interna&#231;&#227;o atual. O crit&#233;rio utilizado para diagn&#243;stico de diabetes mellitus foi de duas dosagens de glicemia em jejum maior ou igual a 140 mg/dl<sup>23</sup> na fase inicial do estudo e maior ou igual a 126 mg/dl a partir de julho de 1997, de acordo com a defini&#231;&#227;o da American Diabetes Association<sup>24</sup>.</p>
    <p>Angina est&#225;vel foi graduada de acordo com a classifica&#231;&#227;o da <italic>Canadian Cardiovascular Society</italic> (CCS)<sup>25</sup>. Angina inst&#225;vel foi definida como angina de recente come&#231;o, progressiva, em repouso e p&#243;s infarto. Infarto agudo do mioc&#225;rdio foi definido de acordo com a Organiza&#231;&#227;o Mundial de Sa&#250;de<sup>26,27</sup>. Foram considerados portadores de s&#237;ndromes coronarianas agudas aqueles com angina inst&#225;vel ou infarto agudo do mioc&#225;rdio.</p>
    <p>Doen&#231;a multiarterial foi definida como presen&#231;a de estenose &gt;50% para o tronco da coron&#225;ria esquerda ou &gt;70% ocorrendo em pelo menos duas das coron&#225;rias de distribui&#231;&#227;o (coron&#225;ria direita, descendente anterior ou circunflexa).</p>
    <p>Disfun&#231;&#227;o ventricular esquerda foi definida, por avalia&#231;&#227;o visual, semiquantitativamente, como discreta, moderada e severa.</p>
    <p>Sucesso do procedimento: definido quando o local tratado apresentava uma les&#227;o residual menor que 20% ao final do procedimento. Sucesso cl&#237;nico: ocorria quando sucesso do procedimento era obtido na aus&#234;ncia de complica&#231;&#245;es maiores (IAM, RM ou &#243;bito) na fase intra-hospitalar. Complica&#231;&#245;es maiores: ocorr&#234;ncia de IAM, necessidade de cirurgia de revasculariza&#231;&#227;o do mioc&#225;rdio ou &#243;bito, sempre considerando a complica&#231;&#227;o mais importante. Insucesso n&#227;o complicado: ocorria quando a les&#227;o n&#227;o era dilatada com sucesso, sendo a evolu&#231;&#227;o intra-hospitalar sem complica&#231;&#245;es.</p>
    <p><italic>An&#225;lise estat&#237;stica</italic> - An&#225;lise estat&#237;stica foi realizada utilizando o pacote estat&#237;stico SPSS vers&#227;o 9.0 para Windows. Vari&#225;veis cont&#237;nuas foram expressas em valor m&#233;dio &#177; desvio padr&#227;o. Vari&#225;veis categ&#243;ricas foram expressas em propor&#231;&#245;es. Utilizou-se o teste do qui quadrado ou o teste exato de Fisher para testar as diferen&#231;as entre propor&#231;&#245;es. Utilizaram-se os <italic>odds ratio (OR)</italic> e seus respectivos intervalos de confian&#231;a para 95% (IC 95%), como estimativas das raz&#245;es de preval&#234;ncia dos riscos de associa&#231;&#227;o entre as vari&#225;veis. Modelos de regress&#227;o log&#237;stica progressiva foram constru&#237;dos incluindo vari&#225;veis cl&#237;nicas (idade, diabetes mellitus, sexo, hipertens&#227;o arterial sist&#234;mica, dislipidemia, tabagismo, quadro cl&#237;nico, infarto pr&#233;vio, interven&#231;&#227;o coron&#225;ria percut&#226;nea pr&#233;via, cirurgia de revasculariza&#231;&#227;o do mioc&#225;rdio pr&#233;via, doen&#231;a multiarterial, disfun&#231;&#227;o ventricular esquerda e choque cardiog&#234;nico) e angiogr&#225;ficas (angula&#231;&#227;o, bifurcac&#227;o, calcifica&#231;&#227;o, contorno irregular, excentricidade, extens&#227;o, les&#227;o ostial, tortuosidade, presen&#231;a de trombo, oclus&#227;o total). Valores de p<underline>&lt;</underline>0,05 foram considerados estatisticamente significantes.</p>
    <p>
      <bold>Resultados</bold>
    </p>
    <p>O sucesso do procedimento foi observado em 98,9%. Sucesso cl&#237;nico foi observado em 95,7%, insucesso n&#227;o complicado em 0,1% e complica&#231;&#245;es maiores em 4,2%. A complica&#231;&#227;o mais freq&#252;ente foi morte em 22 pacientes (2,3%), seguida de infarto do mioc&#225;rdio em 15 (1,6%) e revasculariza&#231;&#227;o do mioc&#225;rdio em 3 pacientes (0,3%). Excluindo pacientes em choque cardiog&#234;nico, ocorreram 11 &#243;bitos (1,2%), 14 infartos do mioc&#225;rdio (1,5%) e 3 revasculariza&#231;&#245;es do mioc&#225;rdio (0,3%).</p>
    <p><italic>Caracter&#237;sticas cl&#237;nicas -</italic> Os resultados intra-hospitalares da an&#225;lise univariada, de acordo com as caracter&#237;sticas cl&#237;nicas, est&#227;o sumarizados na <xref ref-type="table" rid="t3">tabela 3</xref>. Menor sucesso do procedimento foi observado em pacientes com hist&#243;ria pr&#233;via de cirurgia de revasculariza&#231;&#227;o do mioc&#225;rdio (96,5% vs. 99,2%; p=0,054). As vari&#225;veis relacionadas com menor sucesso cl&#237;nico foram: quadro cl&#237;nico (97,4% para angina est&#225;vel; 96,2% para angina inst&#225;vel e 90,7% para infarto agudo do mioc&#225;rdio; p=0,001); choque cardiog&#234;nico (45,5% vs. 96,9%; p=0,0001); diabetes mellitus (92,6% vs. 96,7%; p=0,006), doen&#231;a multiarterial (94,2% vs. 97.1%; p=0,04); hipertens&#227;o arterial sist&#234;mica (94,8% vs. 97,8%; p=0,051) e disfun&#231;&#227;o ventricular esquerda moderada a severa (92,3% vs. 97.0%; p=0,002). Complica&#231;&#245;es maiores estiveram relacionadas com quadro cl&#237;nico (2,6% para angina est&#225;vel; 3,5% para angina inst&#225;vel e 9,3% para infarto agudo do mioc&#225;rdio; p=0,001); choque cardiog&#234;nico (54,5% vs. 3,1%; p=0,0001); diabetes mellitus (7,0% vs. 3,3%; p=0,013); doen&#231;a multiarterial (5,8% vs. 2,7%; p=0,02) e disfun&#231;&#227;o ventricular esquerda moderada a severa (7,7% vs. 2,8%; p=0,0008). Entre as complica&#231;&#245;es maiores, nenhuma vari&#225;vel foi preditora de infarto do mioc&#225;rdio. Les&#227;o resten&#243;tica foi preditora de revasculariza&#231;&#227;o do mioc&#225;rdio (4,3% vs. 0,1%; p=0,007). Morte intra-hospitalar esteve relacionada com sexo feminino (3,6% vs. 1,6%; p=0,05), idade <underline>&gt;</underline>65 anos (3,8% vs. 1,4%; p&lt;0,02), choque cardiog&#234;nico (50% vs. 1,2%; p&lt;0,0001), hipertens&#227;o arterial sist&#234;mica (3,1% vs. 0,4%; p&lt;0,01), revasculariza&#231;&#227;o mioc&#225;rdica pr&#233;via (5,8% vs. 2,0%; p&lt;0,05), doen&#231;a multiarterial (3,4% vs. 1,3%; p&lt;0,03), disfun&#231;&#227;o ventricular esquerda moderada a severa (5,9% vs. 0,7%; p&lt;0,0001) e s&#237;ndromes coronarianas agudas (0,5% para angina est&#225;vel, 1,7% para angina inst&#225;vel e 7,7% para infarto do mioc&#225;rdio; p&lt;0,0001).</p>
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    <p><italic>Caracter&#237;sticas angiogr&#225;ficas, tipo de les&#227;o e art&#233;ria tratada -</italic> Os resultados intra-hospitalares da an&#225;lise univariada, de acordo com as caracter&#237;sticas angiogr&#225;ficas e tipo de les&#227;o, est&#227;o sumarizados na <xref ref-type="table" rid="t4">tabela 4</xref> e de acordo com a art&#233;ria tratada na <xref ref-type="table" rid="t5">tabela 5</xref>. Menor sucesso do procedimento foi observado em les&#245;es calcificadas (95,4% vs. 99,5%; p=0,001); em les&#245;es com contorno irregular (97,8% vs. 99,7%; p=0,004) e em les&#245;es longas (97,3% em les&#245;es <underline>&gt;</underline> 20 mm; 97,6% em les&#245;es <underline>&gt;</underline> 10 mm e 99,5% em les&#245;es &lt; 10 mm; p=0,03). Menor sucesso cl&#237;nico (91,5% vs. 96,3%; p=0,014) e maior percentual de complica&#231;&#245;es (8,5% vs. 3,6%; p=0,01) foram observados em les&#245;es calcificadas. Les&#245;es com extens&#227;o maior ou igual a 10 mm apresentaram menor sucesso do procedimento (97,6% vs. 99,5%; p=0,012), menor sucesso cl&#237;nico (93,7% vs. 96,4%; p=0,052) e maior percentual de complica&#231;&#245;es (6,3% vs. 3,4%; p=0,04). Oclus&#245;es totais apresentaram menor sucesso cl&#237;nico (92,1% vs. 96,2%; p=0,04) e maior percentual de complica&#231;&#245;es (7,9% vs. 3,7%; p=0,03). Menor sucesso cl&#237;nico (94,7% vs. 98,3%; p=0,01) e maior percentual de complica&#231;&#245;es (5,3% vs. 1,4%; p=0,003) foram observados em les&#245;es complexas (les&#245;es tipo B2 e C). Da mesma forma, les&#245;es em tronco da coron&#225;ria esquerda apresentaram menor sucesso cl&#237;nico e maior percentual de complica&#231;&#245;es, quando comparados com les&#245;es tratadas em descendente anterior (p&lt;0,006), coron&#225;ria direita (p&lt;0,003), circunflexa (p&lt;0,004) e pontes de veias safena (p&lt;0,04).</p>
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    <p><italic>An&#225;lise multivariada &#150; caracter&#237;sticas cl&#237;nicas -</italic> Os resultados da an&#225;lise multivariada, de acordo com as caracter&#237;sticas cl&#237;nicas, est&#227;o sumarizados na <xref ref-type="table" rid="t6">tabela 6</xref>. Interven&#231;&#227;o coron&#225;ria pr&#233;via (les&#227;o resten&#243;tica) foi o &#250;nico preditor cl&#237;nico independente de menor sucesso do procedimento (OR = 0,18; IC 95% = 0,04 &#150; 0,88; p=0,04). As vari&#225;veis cl&#237;nicas identificadas como preditoras independentes de menor sucesso cl&#237;nico foram: diabetes mellitus (OR = 0,47; IC 95% = 0,24 &#150; 0,90; p=0,02); choque cardiog&#234;nico (OR = 0,03; IC 95% = 0,01 &#150; 0,65; p=0,00001); s&#237;ndromes coronarianas agudas (OR = 0,48; IC 95% = 0,23 &#150; 0,98; p=0,04); idade (OR = 1,03; IC 95% = 1,00 &#150; 1,06; p=0,03) e disfun&#231;&#227;o ventricular esquerda moderada a severa (OR = 0,44; IC 95% = 0,23 &#150; 0,84; p=0,01). As vari&#225;veis cl&#237;nicas identificadas como preditoras independentes de complica&#231;&#245;es maiores foram: diabetes mellitus (OR = 2,00; IC 95% = 1,03 &#150; 3,88; p=0,04); choque cardiog&#234;nico (OR = 40,20; IC 95% = 15,72 &#150; 102,79; p=0,00001); s&#237;ndromes coronarianas agudas (OR = 0,47; IC 95% = 0,30 &#150; 0,71; p=0,0004); idade (OR = 0,97; IC 95% = 0,94 &#150; 0,99; p=0,03); doen&#231;a multiarterial (OR = 2,15; IC 95% = 1,08 &#150; 4,30; p=0,03) e disfun&#231;&#227;o ventricular esquerda moderada a severa (OR = 2,55; IC 95% = 1,33 &#150; 4,89; p=0,005). Idade (OR = 0,0015; IC 95% = 0,87 &#150; 0,97; p&lt;0,002), choque cardiog&#234;nico (OR = 104,80; IC 95% = 32,68 &#150; 336,07; p=0,00001), hipertens&#227;o arterial sist&#234;mica (OR = 7,68; IC 95% = 1,09 &#150; 58,67; p=0,05), disfun&#231;&#227;o ventricular esquerda moderada a severa (OR = 6,82; IC 95% = 2,42 &#150; 19,20; p=0,0003) e s&#237;ndromes coronarianas agudas (OR = 6,98; IC 95% = 1,58 &#150; 30,74; p=0,01) foram preditores independentes de mortalidade intra-hospitalar.</p>
    <p content-type="asset">
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    <p><italic>An&#225;lise multivariada &#150; caracter&#237;sticas angiogr&#225;ficas -</italic> Os resultados da an&#225;lise multivariada, de acordo com as caracter&#237;sticas angiogr&#225;ficas, est&#227;o sumarizados na <xref ref-type="table" rid="t6">tabela 6</xref>. Entre as vari&#225;veis angiogr&#225;ficas, calcifica&#231;&#227;o (OR = 0,13; IC 95% = 0,04 &#150; 0,43; p=0,0009) e contorno irregular (OR = 0,15; IC 95% = 0,03 &#150; 0,72; p=0,02) foram preditoras de menor sucesso do procedimento. Calcifica&#231;&#227;o (OR = 0,40; IC 95% = 0,20 &#150; 0,81; p=0,01) e oclus&#227;o total (OR = 0,44; IC 95% = 0,21 &#150; 0,91; p=0,03) foram preditoras de menor sucesso cl&#237;nico. Calcifica&#231;&#227;o (OR = 2,98; IC 95% = 1,48 &#150; 6,00; p=0,002); les&#245;es com extens&#227;o maior ou igual a 10 mm (OR = 1,91; IC 95%= 1,02 &#150; 3,55; p=0,04) e oclus&#227;o total (OR = 2,43; IC 95% = 1,16 &#150; 5,10; p=0,02) foram preditoras de maior ocorr&#234;ncia de complica&#231;&#245;es.</p>
    <p>
      <bold>Discuss&#227;o</bold>
    </p>
    <p>Desde a introdu&#231;&#227;o da angioplastia transluminal coron&#225;ria percut&#226;nea em 1977<sup>1</sup>, a utiliza&#231;&#227;o das interven&#231;&#245;es coron&#225;rias percut&#226;neas tem expandido rapidamente. Devido ao grande n&#250;mero de procedimentos realizados, associados ao risco de morbidade e mortalidade, numerosos estudos t&#234;m identificado fatores determinantes de resultados imediatos e a longo prazo<sup>7-21</sup>.</p>
    <p>Verificamos que nossos resultados est&#227;o de acordo com diversos estudos publicados previamente. Entre as v&#225;rias s&#233;ries publicadas, o sucesso do procedimento ocorre entre 95 a 99%, o sucesso cl&#237;nico entre 86 a 96% e complica&#231;&#245;es maiores entre 3,5 a 13,2% (morte entre 0,4 a 3,5%; revasculariza&#231;&#227;o do mioc&#225;rdio entre 2,1 a 6,0% e infarto do mioc&#225;rdio entre 0,9 e 6,8%)<sup>7,9-11,28-30</sup>. A varia&#231;&#227;o observada entre sucesso cl&#237;nico e complica&#231;&#245;es maiores decorreu, principalmente, de maior preval&#234;ncia de pacientes com idade avan&#231;ada, disfun&#231;&#227;o ventricular esquerda e, principalmente, choque cardiog&#234;nico, al&#233;m do per&#237;odo do estudo e do uso de outras t&#233;cnicas de interven&#231;&#227;o coron&#225;ria percut&#226;nea associadas aos stents. Choque cardiog&#234;nico &#233; a principal causa de mortalidade em pacientes internados por infarto agudo do mioc&#225;rdio, variando de 26 a 72%<sup>31,32</sup>. Sutton e cols.<sup>33</sup> analisaram, retrospectivamente, 113 pacientes em choque cardiog&#234;nico tratados por interven&#231;&#245;es coron&#225;rias percut&#226;neas. Semelhante aos nossos resultados, a mortalidade foi de 51%. Os autores identificaram que idade &gt;70 anos, infarto do mioc&#225;rdio pr&#233;vio e fal&#234;ncia do tratamento trombol&#237;tico foram vari&#225;veis independentes relacionadas a mortalidade intra-hospitalar.</p>
    <p><italic>Efeito das vari&#225;veis cl&#237;nicas -</italic> Neste estudo, pacientes com idade avan&#231;ada, diabetes mellitus, s&#237;ndromes coronarianas agudas, choque cardiog&#234;nico e disfun&#231;&#227;o ventricular esquerda moderada a severa apresentaram menor sucesso cl&#237;nico e maior percentual de complica&#231;&#245;es intra-hospitalares. Pacientes multiarteriais apresentaram maior percentual de complica&#231;&#245;es. Les&#227;o resten&#243;tica foi vari&#225;vel preditora de menor sucesso do procedimento e de ocorr&#234;ncia de revasculariza&#231;&#227;o do mioc&#225;rdio intra-hospitalar. Idade, choque cardiog&#234;nico, hipertens&#227;o arterial sist&#234;mica, disfun&#231;&#227;o ventricular esquerda moderada a severa e s&#237;ndromes coronarianas agudas foram preditores independentes de mortalidade intra-hospitalar. O'Connor e cols.<sup>34</sup> identificaram idade, choque cardiog&#234;nico, procedimentos de urg&#234;ncia/emerg&#234;ncia, disfun&#231;&#227;o ventricular esquerda, uso de bal&#227;o intra-a&#243;rtico e les&#245;es tipo C como preditores independentes de mortalidade. Disfun&#231;&#227;o renal e insufici&#234;ncia card&#237;aca tamb&#233;m foram preditores de morte. Estas duas &#250;ltimas vari&#225;veis e uso de bal&#227;o intra-a&#243;rtico n&#227;o foram inclu&#237;das em nossa an&#225;lise porque os dados n&#227;o estavam dispon&#237;veis em todos os pacientes. Resnic e cols.<sup>13</sup> identificaram fatores preditores de mortalidade semelhantes, incluindo choque cardiog&#234;nico, insufici&#234;ncia card&#237;aca, taquicardia, insufici&#234;ncia renal, idade <underline>&gt;</underline> 75 anos, infarto agudo do mioc&#225;rdio e angina inst&#225;vel. Block e cols.<sup>30</sup> analisaram os dados de 8 diferentes estudos e identificaram um n&#250;mero de vari&#225;veis preditoras de eventos adversos p&#243;s-interven&#231;&#245;es coron&#225;rias percut&#226;neas. As vari&#225;veis identificadas como preditoras de morte foram: idade em 8 bancos de dados, diabetes em 6, choque cardiog&#234;nico em 4, disfun&#231;&#227;o ventricular esquerda em 7, doen&#231;a multiarterial em 5 e s&#237;ndromes coron&#225;rias agudas em 3. Idade foi preditora de infarto do mioc&#225;rdio em 2 bancos de dados, doen&#231;a multiarterial em 2, s&#237;ndromes isqu&#234;micas agudas em 2, choque cardiog&#234;nico em 1 e les&#227;o resten&#243;tica em 2. Disfun&#231;&#227;o ventricular esquerda foi preditora de revasculariza&#231;&#227;o do mioc&#225;rdio em 2 bancos de dados, s&#237;ndromes isqu&#234;micas agudas em 1, choque cardiog&#234;nico em 3 e les&#227;o resten&#243;tica em 1.</p>
    <p>Efeito das vari&#225;veis angiogr&#225;ficas, art&#233;ria tratada e tipo de les&#227;o - De todas as caracter&#237;sticas angiogr&#225;ficas inclu&#237;das na classifica&#231;&#227;o da American College of Cardiology/American Heart Association, calcifica&#231;&#227;o, extens&#227;o da les&#227;o, oclus&#227;o total e contorno irregular foram identificadas como preditoras de resultados imediatos. Outros estudos t&#234;m buscado identificar quais caracter&#237;sticas angiogr&#225;ficas, tipo de les&#227;o e art&#233;ria tratada est&#227;o relacionados aos resultados<sup>7,18</sup>.</p>
    <p>Em nosso estudo, calcifica&#231;&#227;o foi preditora de menor sucesso do procedimento, menor sucesso cl&#237;nico e maior ocorr&#234;ncia de complica&#231;&#245;es. Les&#245;es calcificadas levam a redu&#231;&#227;o da distens&#227;o do vaso ocorrendo expans&#227;o inadequada do stent, o que acarreta menor sucesso e maior possibilidade de complica&#231;&#245;es<sup>35,36</sup>. Ellis e cols.<sup>7</sup> estudaram 10.907 les&#245;es e identificaram calcifica&#231;&#227;o com preditora independente de complica&#231;&#245;es isqu&#234;micas.</p>
    <p>Les&#245;es com contorno irregular foram preditoras de menor sucesso do procedimento, enquanto que no estudo de Ellis e cols.<sup>7</sup> contorno irregular foi preditor independente de complica&#231;&#245;es isqu&#234;micas.</p>
    <p>Na nossa an&#225;lise, oclus&#227;o total foi vari&#225;vel preditora independente de menor sucesso cl&#237;nico e de maior ocorr&#234;ncia de complica&#231;&#245;es. Oclus&#245;es totais compreendem um amplo espectro que vai desde oclus&#245;es recentes, secund&#225;rias &#224; ruptura da placa ateroscler&#243;tica e oclus&#227;o do vaso (97,6% da nossa casu&#237;stica); at&#233; oclus&#245;es cr&#244;nicas, quando o trombo est&#225; organizado (2,4% do total de oclus&#245;es)<sup>37,38</sup>. Na an&#225;lise de Ellis e cols.<sup>7</sup> oclus&#227;o total com dura&#231;&#227;o &lt; 3 meses foi a vari&#225;vel angiogr&#225;fica mais fortemente relacionada com ocorr&#234;ncia de complica&#231;&#245;es isqu&#234;micas intra-hospitalares. No nosso estudo, diferente dos resultados de Ellis e cols.<sup>7</sup>, calcifica&#231;&#227;o foi a vari&#225;vel mais fortemente relacionada com sucesso e complica&#231;&#245;es.</p>
    <p>Estudos pr&#233;vios t&#234;m demonstrado que extens&#227;o da les&#227;o est&#225; diretamente relacionada com percentual de complica&#231;&#245;es<sup>7,39,40</sup>, o que est&#225; de acordo com os nossos achados. Kornowski e cols.<sup>39</sup> demonstraram que complica&#231;&#245;es maiores foram mais freq&#252;entes em les&#245;es longas (3,4% vs. 1,0%; p=0,04). No estudo de Ellis e cols.<sup>7</sup>, extens&#227;o da les&#227;o entre 10 e 20 mm foi preditora independente de complica&#231;&#245;es isqu&#234;micas.</p>
    <p>Les&#245;es em tronco da coron&#225;ria esquerda e na descendente anterior t&#234;m sido descritas como preditoras de complica&#231;&#245;es imediatas<sup>15,16</sup>. Block e cols.<sup>30</sup> verificaram que les&#245;es em tronco da coron&#225;ria esquerda foram preditoras de mortalidade hospitalar em 2 estudos. No nosso estudo, les&#245;es em tronco da coron&#225;ria esquerda foram preditoras de complica&#231;&#245;es maiores, n&#227;o sendo observado signific&#226;ncia estat&#237;stica ao analisarmos as outras art&#233;rias.</p>
    <p>V&#225;rios estudos t&#234;m demonstrado o valor preditivo da classifica&#231;&#227;o da ACC/AHA ao analisar os resultados imediatos p&#243;s-interven&#231;&#245;es coron&#225;rias percut&#226;neas<sup>15,30</sup>. No entanto, o valor preditivo do tipo de les&#227;o tem sido menor que o observado previamente, devido ao refinamento t&#233;cnico, incluindo percentual elevado de implante de stents e utiliza&#231;&#227;o de inibidores de glicoprote&#237;nas plaquet&#225;rias IIb/IIIa. Krone e cols.<sup>18</sup> verificaram que a classifica&#231;&#227;o da ACC/AHA apresentou menor poder de discrimina&#231;&#227;o de resultados imediatos p&#243;s-interven&#231;&#245;es coron&#225;rias percut&#226;neas do que a classifica&#231;&#227;o da Society for Angiography and Interventions (SCAI), n&#227;o utilizada em nosso estudo. No nosso estudo, apesar de les&#245;es complexas apresentarem menor sucesso cl&#237;nico e maior percentual de complica&#231;&#245;es, resolvemos n&#227;o incluir tipo de les&#227;o no modelo multivari&#225;vel. Esta op&#231;&#227;o deveu-se ao fato de que todas as caracter&#237;sticas angiogr&#225;ficas da classifica&#231;&#227;o ACC/AHA foram inclu&#237;das no nosso modelo e, portanto, a inclus&#227;o da vari&#225;vel tipo de les&#227;o seria inadequada.</p>
    <p><italic>Limita&#231;&#245;es -</italic> O nosso estudo &#233; observacional, n&#227;o randomizado, de pacientes consecutivamente tratados com implante de stents coron&#225;rios. N&#227;o podemos generalizar os achados; por se tratar de centro de refer&#234;ncia, os pacientes podem ter particularidades que modificaram os resultados e que n&#227;o conseguimos controlar. Algumas vari&#225;veis n&#227;o foram analisadas, como por exemplo, fun&#231;&#227;o renal e &#237;ndice de massa corp&#243;rea. Al&#233;m disso, n&#227;o avaliamos o controle glic&#234;mico em diab&#233;ticos, fator relacionado com menor ocorr&#234;ncia de revasculariza&#231;&#227;o da les&#227;o-alvo, re-hospitaliza&#231;&#227;o e recorr&#234;ncia de angina<sup>41</sup>. Contudo, nossa experi&#234;ncia representa o mundo real e n&#227;o de estudos cl&#237;nicos randomizados. Determinadas caracter&#237;sticas foram observadas em pequeno n&#250;mero; sendo assim, podem n&#227;o ter alcan&#231;ado signific&#226;ncia estat&#237;stica devido ao pequeno tamanho amostral (erro tipo II). Outra limita&#231;&#227;o diz respeito &#224; an&#225;lise das les&#245;es, realizadas apenas por um observador. N&#227;o avaliamos o grau de estenose atrav&#233;s de angiografia coron&#225;ria quantitativa (ACQ), m&#233;todo mais preciso que a avalia&#231;&#227;o visual<sup>42,43</sup>, apesar de j&#225; termos demonstrado boa correla&#231;&#227;o entre a ACQ e a estimativa visual<sup>44</sup>. Da mesma forma, a fun&#231;&#227;o ventricular esquerda foi estimada por avalia&#231;&#227;o visual, n&#227;o sendo utilizado nenhum dos m&#233;todos de imagem que estimam a fun&#231;&#227;o ventricular esquerda de forma mais acurada, al&#233;m de identificar a regi&#227;o do ventr&#237;culo com disfun&#231;&#227;o<sup>45</sup>.</p>
    <p>
      <bold>Conclus&#227;o</bold>
    </p>
    <p>Fatores cl&#237;nicos e angiogr&#225;ficos influenciaram de maneira significativa os resultados intra-hospitalares p&#243;s-implante de stent. Calcifica&#231;&#227;o, contorno irregular e les&#245;es resten&#243;ticas foram identificados como preditores independentes de sucesso do procedimento. Nossa an&#225;lise identificou 4 fatores cl&#237;nicos (choque cardiog&#234;nico, s&#237;ndromes coron&#225;rias agudas, disfun&#231;&#227;o ventricular esquerda e idade <underline>&gt;</underline>65 anos) como preditores independentes de sucesso cl&#237;nico, complica&#231;&#245;es maiores e mortalidade intra-hospitalar. Diabetes mellitus foi preditor independente de sucesso cl&#237;nico e complica&#231;&#245;es maiores. Oclus&#227;o total e calcifica&#231;&#227;o foram identificados como preditores independentes de sucesso cl&#237;nico e complica&#231;&#245;es maiores. Estes fatores podem ser utilizados para verificar a possibilidade de sucesso e complica&#231;&#245;es maiores na fase intra-hospitalar, p&#243;s-implante de stent coron&#225;rio.</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> Ant&#244;nio Jos&#233; N&#233;ri-Souza </p>
        <p> Rua Tenente Fernando Tuy, 318/1701 </p>
        <p> 41810-780 &#150; Salvador, BA </p>
        <p> E-mail: </p>
        <p>
          <email xlink:href="nerisouza@cardiol.br">nerisouza@cardiol.br</email>
        </p>
      </fn>
    </p>
    <p>Recebido em 27/03/05 </p>
    <p> Aceito em 11/11/05</p>
  </body>
  <back>
    <ref-list>
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        <label>1</label>
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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">Independent predictors of in-hospital outcomes following coronary stent implantation</article-title>
      </title-group>
      <abstract xml:lang="en">
        <p>OBJECTIVE: To identify the clinical and angiographic predictors of early outcome following coronary stent implantation. METHODS: Nine hundred and forty-six patients (pt) [61.04 &#177; 10.98 years old, range 31 to 91] underwent stent implantation; 580 male (61.3%). Procedural success was defined when a pt had at least one vessel successfully dilated with a residual stenosis &lt; 20%. Clinical success occured when a pt had at least one vessel successfully dilated without a major complication (MC) [death, myocardial infarction (MI), coronary artery bypass graft] during the hospital stay. Clinical and angiographic determinants of outcome were studied. All variables related to early outcome evaluated by univariate analysis were included in a multiple logistic regression analysis (MLR). RESULTS: Procedural success was achieved in 98.9%; clinical success in 95.7%; an unsuccessful uncomplicated outcome in 0.1% and major complications in 4.2%. By MLR, procedural success was related to restenotic lesion, calcification, and irregular contour. Clinical success was related to diabetes mellitus, cardiogenic shock, acute coronary syndromes, age, left ventricular dysfunction, calcification, and total occlusion. Major complications was predicted by diabetes mellitus, cardiogenic shock, acute coronary syndromes, age, multivessel disease, left ventricular dysfunction, calcification, long lesions, and total occlusions. Mortality was predicted by cardiogenic shock, acute coronary syndromes, age, arterial hypertension, and left ventricular dysfunction. CONCLUSION: These results suggest that early outcome was significantly affected by cardiogenic shock, left ventricular dysfunction, age, calcification, and total occlusion.</p>
      </abstract>
      <kwd-group xml:lang="en">
        <kwd>Stent</kwd>
        <kwd>risk factors</kwd>
        <kwd>multivariate analisys</kwd>
        <kwd>coronary arterioclerosis</kwd>
        <kwd>angina pectoris</kwd>
      </kwd-group>
    </front-stub>
    <body>
      <p>
        <bold>ORIGINAL ARTICLE</bold>
      </p>
      <p>
        <bold>Independent predictors of in-hospital outcomes following coronary stent implantation</bold>
      </p>
      <p>
        <bold>Ant&#244;nio Jos&#233; Neri-Souza; Bruno Machado Aguiar; Andr&#233; Borges Coelho; Anderson Jorge Lima Nascimento; Waldemar Souza Oliveira J&#250;nior; Antonio Gilson Lapa Godinho; Nilson Borges Ramos; &#193;lvaro Rabelo J&#250;nior</bold>
      </p>
      <p>Funda&#231;&#227;o Bahiana de Cardiologia, Universidade Federal da Bahia - Salvador, BA - Brazil</p>
      <p>
        <xref ref-type="corresp" rid="back-body2">Correspond&#234;ncia</xref>
      </p>
      <p>
        <bold>ABSTRACT</bold>
      </p>
      <p><bold>OBJECTIVE:</bold> To identify independent clinical and angiographic predictors determining early outcomes following coronary stent implantation.</p>
      <p><bold>METHODS:</bold> Nine hundred and forty six patients with a mean age of 61.04 &#177; 10.98 years (31 to 91 years of age) underwent stent implantation; 580 were males (61.3%). Procedural success was defined when a patient had at least one vessel successfully dilated with a residual stenosis &lt; 20%. Clinical success occurred when the procedure was successful and no major complications occurred (MI, need for CABG, or death) during the hospital stay. Clinical and angiographic characteristics were analyzed. All variables related to early outcomes as assessed by the univariate analysis were included in the logistic regression model.</p>
      <p><bold>RESULTS:</bold> Procedural success was achieved in 98.9%, clinical success in 95.7%, uncomplicated unsuccessful outcomes occurred in 0.1%, and major complications in 4.2%. The multivariate analysis showed that restenotic lesion, calcification, and irregular contour were related to procedural success. Diabetes mellitus, cardiogenic shock, acute coronary syndromes, age, left ventricular dysfunction, calcification, and total occlusion were predictors of clinical success. Diabetes mellitus, cardiogenic shock, acute coronary syndromes, age, multivessel disease, left ventricular dysfunction, calcification, long lesions, and total occlusion were predictors of major complications, whereas cardiogenic shock, acute coronary syndromes, age, hypertension, and left ventricular dysfunction were predictors of in-hospital mortality.</p>
      <p><bold>CONCLUSION:</bold> Our results suggest that the early outcomes following stent implantation were significantly related to cardiogenic shock, left ventricular dysfunction, age, calcification, and total occlusion.</p>
      <p><bold>Key words:</bold> Stent, risk factors, multivariate analysis, coronary arteriosclerosis, angina pectoris.</p>
      <p>The introduction of percutaneous transluminal coronary angioplasty by Gr&#252;ntzig<sup>1</sup> in 1977 represented a milestone in the treatment of coronary artery disease (CAD), and its indications became remarkably more widespread thereafter. Several factors contributed to increase success rates and reduce the number of complications, in addition to broadening the indications for the procedure, such as greater operator's expertise and technological evolution represented by the use of stents and platelet glycoprotein IIb/IIIa inhibitors<sup>2-4</sup>.</p>
      <p>Concurrently, clinical and angiographic characteristics as well as characteristics related to the procedure have been identified as determinants of early outcomes. Based on these observations, the American College of Cardiology and the American Heart Association conceived a classification according to angiographic criteria to estimate the probability of early success and occurrence of complications<sup>5-6</sup>.</p>
      <p>Several studies have sought to identify predictors of in-hospital outcomes following stent implantation, and some authors have developed prediction models of in-hospital events<sup>7-21</sup>. Risk estimates are important to assess outcomes as well as to help patients and their relatives to consent to the performance of the procedure. They are also important to help doctors choose or avoid a determined strategy or medication during the procedure.</p>
      <p>Our objective is to analyze in-hospital outcomes of patients undergoing stent implantation, and to identify independent clinical and angiographic predictors related to success and major complications.</p>
      <p>
        <bold>Methods</bold>
      </p>
      <p><italic>Patients</italic> - Nine hundred and forty six patients consecutively underwent stent implantation in 1,045 lesions from October 1995 to December 2002. Five hundred and eighty patients were males (61.3%) and 366 were females (38.7%), with a mean age of 61.04 &#177; 10.98 (31 to 91) years. Two hundred and forty three patients (25.7%) had diabetes mellitus, 677 (71.6%) had hypertension, 694 (73.4%) had dyslipidemia, and 291 patients were smokers (25.5%). Two hundred and fifty nine patients had previous history of infarction (27.4%), 86 of coronary artery bypass grafting (9.1%), and 47 of previous percutaneous coronary intervention in the treated vessel, and which were, therefore, restenotic lesions (5.0%). Four hundred and sixty six patients had multivessel lesions (49.3%) and 273 had moderate to severe left ventricular dysfunction (28.9%). Prior to the intervention, 420 patients had stable angina (44.4%), 344 had unstable angina (36.4%) and 182 had acute myocardial infarction (19.2%). Twenty two of the patients with MI were in cardiogenic shock (2.2%). The clinical characteristics are summarized in <xref ref-type="table" rid="tabela1-body2">Table 1</xref>.</p>
      <table-wrap id="tabela1-body2">
        <graphic xlink:href="1678-4170-abc-87-04-0429-00006-gt01-en.jpg"/></table-wrap>
      <p><italic>Lesions</italic> - One thousand and forty five lesions (1.11 lesion/patient) were treated, 536 of them in the left anterior descending (51.2%), 313 in the right coronary artery (30.0%), 157 in the left circumflex (15.0%), 8 in the left main coronary (0.8%), 25 saphenous vein bypass graft (2.4%) and 6 in the anastomosis of the left internal mammary artery to the left anterior descending (0.6%). Thirty five lesions (3.4%) involved angulations <underline>&gt;</underline> 45%, 145 were bifurcation lesions (13.9%), 130 were calcified lesions (12.4%), 402 had irregular contours (38.5%), 286 lesions were <underline>&gt;</underline> 10 mm long (27.4%), 127 were total occlusions (12.2%), 33 were ostial lesions (3.2%), 32 lesions had moderate to severe tortuosity in the proximal segment (3.1%) and 223 lesions had thrombus (21.3%). Seven hundred and fifty seven lesions were type B2 and C, considered complex lesions (72.4%). The angiographic characteristics are summarized in <xref ref-type="table" rid="tabela2-body2">Table 2</xref>.</p>
      <table-wrap id="tabela2-body2">
        <graphic xlink:href="1678-4170-abc-87-04-0429-00006-gt02-en.jpg"/></table-wrap>
      <p><italic>Procedure</italic> - The stent implantation procedure has already been described. The femoral approach was used in 95% of the cases<sup>22</sup>. Intravenous heparin was given in bolus (5,000 to 10,000 IU) following femoral artery puncture. Different types of stents were implanted under fluoroscopic guidance. The extension and diameter of the stents used were chosen by the operators. The final outcome was based on angiographic control. All patients were given aspirin (100 to 200 mg orally, once a day) and ticlopidine (250 mg orally, twice a day) or clopidogrel (initial dose of 300 mg orally, followed by 75 mg orally, once a day) starting 48 hours prior to the procedure, when clinically possible.</p>
      <p><italic>Definitions</italic> - Diabetes Mellitus: patients were considered to have diabetes if they had been previously diagnosed as such, if they were on medications (oral hypoglycemic agents or insulin), or if they had been diagnosed in the current hospitalization. The criterion used for the diagnosis of diabetes mellitus was two fasting plasma glucose levels <underline>&gt;</underline> 140 mg/dl<sup>23</sup> in the initial phase of the study, and <underline>&gt;</underline> 126 mg/dl as from July 1997 according to the definition of the American Diabetes Association<sup>24</sup>.</p>
      <p>Stable angina was graded according to the Canadian Cardiovascular Society (CCS) classification<sup>25</sup>. Unstable angina was defined as angina of recent onset, progressive angina, angina at rest and post-infarction angina. Acute myocardial infarction was defined according to the World Health Organization<sup>26, 27</sup>. Patients with unstable angina or acute myocardial infarction were considered to have acute coronary syndromes.</p>
      <p>Multivessel disease was defined as the presence of stenosis &gt;50% for the left main coronary or &gt;70% in at least two of the coronary branches (right coronary artery, left anterior descending, or left circumflex).</p>
      <p>Left ventricular dysfunction was semi-quantitatively defined according to visual assessment as mild, moderate and severe.</p>
      <p>Procedural success was defined in cases where the vessel treated presented a residual lesion &lt; 20% at the end of the procedure. Clinical success occurred when procedural success was achieved in the absence of major in-hospital complications (AMI, CABG, or death). Major complications included: AMI, need for coronary artery bypass grafting or death, the most severe complication always being the one considered. Non-complicated unsuccessful outcome occurred when the lesion was not successfully dilated, and no in-hospital complications occurred.</p>
      <p><italic>Statistical analysis</italic> - The SPSS statistical package for Windows version 9.0 was used for the statistical analysis. Continuous variables were expressed as mean value &#177; standard deviation. Categorical variables were expressed as proportions. The chi-square test or the Fisher's exact test was used to test the differences between proportions. Odds ratios (OR) and their respective 95% confidence intervals (95% CI) were used as estimates of prevalence ratios of risks of association between variables. Logistic regression models were constructed including clinical variables (age, diabetes mellitus, sex, systemic hypertension, dyslipidemia, smoking, clinical manifestations, previous infarction, previous percutaneous coronary intervention, previous coronary artery bypass grafting, multivessel disease, left ventricular dysfunction, and cardiogenic shock) and angiographic variables (angulation, bifurcation, calcification, irregular contour, eccentricity, lenght, ostial lesion, tortuosity, presence of thrombus, total occlusion). P values <underline>&lt;</underline>0.05 were considered statistically significant.</p>
      <p>
        <bold>Results</bold>
      </p>
      <p>Procedural success was observed in 98.9% of the cases. Clinical success was observed in 95.7%, non-complicated unsuccessful outcome in 0.1%, and major complications in 4.2%. The most frequent complication was death in 22 patients (2.3%), followed by myocardial infarction in 15 (1.6%), and myocardial revascularization in 3 patients (0.3%). Excluding patients with cardiogenic shock, 11 deaths (1.2%), 14 myocardial infarctions (1.5%), and 3 myocardial revascularizations (0.3%) occurred.</p>
      <p><italic>Clinical characteristics</italic> - In-hospital results of the univariate analysis according to clinical characteristics are summarized in <xref ref-type="table" rid="e06t3-body2">Table 3</xref>. Lower procedural success was observed in patients with a previous history of coronary artery bypass grafting (96.5% versus 99.2%; p=0.054). The variables related to lower clinical success were: clinical manifestations (97.4% for stable angina; 96.2% for unstable angina, and 90.7% for acute myocardial infarction; p=0.001); cardiogenic shock (45.5% versus 96.9%; p=0.0001); diabetes mellitus (92.6% versus 96.7%; p=0.006), multivessel disease (94.2% versus 97.1%; p=0.04); systemic hypertension (94.8% versus 97.8%; p=0.051) and moderate to severe left ventricular dysfunction (92.3% versus 97.0%; p=0.002). Major complications were related to clinical manifestations (2.6% for stable angina; 3.5% for unstable angina and 9.3% for acute myocardial infarction; p=0.001); cardiogenic shock (54.5% versus 3.1%; p=0.0001); diabetes mellitus (7.0% versus 3.3%; p=0.013); multivessel disease (5.8% versus 2.7%; p=0.02) and moderate to severe left ventricular dysfunction (7.7% versus 2.8%; p=0.0008). Among the major complications, no variable was predictive of myocardial infarction. Restenotic lesion was predictive of myocardial revascularization (4.3% versus 0.1%; p=0.007). In-hospital death was related to the female gender (3.6% versus 1.6%; p=0.05), age <underline>&gt;</underline>65 years (3.8% versus 1.4%; p&lt;0.02), cardiogenic shock (50% versus 1.2%; p&lt;0.0001), systemic hypertension (3.1% versus 0.4%; p&lt;0.01), previous myocardial revascularization (5.8% versus 2.0%; p&lt;0.05), multivessel disease (3.4% versus 1.3%; p&lt;0.03), moderate to severe left ventricular dysfunction (5.9% versus 0.7%; p&lt;0.0001) and acute coronary syndromes (0.5% for stable angina, 1.7% for unstable angina and 7.7% for myocardial infarction; p&lt;0.0001).</p>
      <p content-type="asset">
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      <p><italic>Angiographic characteristics, type of lesion and vessel treated</italic> - In-hospital results of the univariate analysis, according to the angiographic characteristics and type of lesion are summarized in <xref ref-type="table" rid="e06t4-body2">Table 4</xref>; and according to the vessel treated are in <xref ref-type="table" rid="e06t5-body2">Table 5</xref>. Lower procedural success was observed in calcified lesions (95.4% versus 99.5%; p=0.001); in lesions with irregular contours (97.8% versus 99.7%; p=0.004) and in long lesions (97.3% in lesions <underline>&gt;</underline> 20 mm; 97.6% in lesions <underline>&gt;</underline> 10 mm and 99.5% in lesions &lt; 10 mm; p=0.03). Lower clinical success (91.5% versus 96.3%; p=0.014) and a higher percentage of complications (8.5% versus 3.6%; p=0.01) were observed in calcified lesions. Lesions <underline>&gt;</underline> 10 mm long showed lower procedural success (97.6% versus 99.5%; p=0.012), lower clinical success (93.7% versus 96.4%; p=0.052) and a higher percentage of complications (6.3% versus 3.4%; p=0.04). Total occlusions showed lower clinical success (92.1% versus 96.2%; p=0.04) and a higher percentage of complications (7.9% versus 3.7%; p=0.03). Lower clinical success (94.7% versus 98.3%; p=0.01) and a higher percentage of complications (5.3% versus 1.4%; p=0.003) were observed in complex lesions (lesions type B2 and C). Likewise, lesions in the left main coronary presented lower clinical success and a higher percentage of complications when compared to lesions treated in the left anterior descending (p&lt;0.006), right coronary artery (p&lt;0.003), left circumflex (p&lt;0.004) and saphenous vein bypasses (p&lt;0.04).</p>
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      <p><italic>Multivariate analysis &#150; clinical characteristics</italic> - The results of the multivariate analysis according to the clinical characteristics are summarized in <xref ref-type="table" rid="e06t6-body2">Table 6</xref>. Previous coronary intervention (restenotic lesion) was the only independent clinical predictor of lower procedural success (OR = 0.18; 95% CI = 0.04 &#150; 0.88; p=0.04). The clinical variables identified as independent predictors of lower clinical success were: diabetes mellitus (OR = 0.47; 95% CI = 0.24 &#150; 0.90; p=0.02); cardiogenic shock (OR = 0.03; 95% CI = 0.01 &#150; 0.65; p=0.00001); acute coronary syndromes (OR = 0.48; 95% CI = 0.23 &#150; 0.98; p=0.04); age (OR = 1.03; 95% CI = 1.00 &#150; 1.06; p=0.03) and moderate to severe left ventricular dysfunction (OR = 0.44; 95% CI = 0.23 &#150; 0.84; p=0.01). The clinical variables identified as independent predictors of major complications were: diabetes mellitus (OR = 2.00; 95% CI = 1.03 &#150; 3.88; p=0.04); cardiogenic shock (OR = 40.20; 95% CI = 15.72 &#150; 102.79; p=0.00001); acute coronary syndromes (OR = 0.47; 95% CI = 0.30 &#150; 0.71; p=0.0004); age (OR = 0.97; 95% CI = 0.94 &#150; 0.99; p=0.03); multivessel disease (OR = 2.15; 95% CI = 1.08 &#150; 4.30; p=0.03) and moderate to severe left ventricular dysfunction (OR = 2.55; 95% CI = 1.33 &#150; 4.89; p=0.005). Age (OR = 0.0015; 95% CI = 0.87 &#150; 0.97; p&lt;0.002), cardiogenic shock (OR = 104.80; 95% CI = 32.68 &#150; 336.07; p=0.00001), systemic hypertension (OR = 7.68; 95% CI = 1.09 &#150; 58.67; p=0.05), moderate to severe left ventricular dysfunction (OR = 6.82; 95% CI = 2.42 &#150; 19.20; p=0.0003) and acute coronary syndromes (OR = 6.98; 95% CI = 1.58 &#150; 30.74; p=0.01) were independent predictors of in-hospital mortality.</p>
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      <p><italic>Multivariate analysis &#150; angiographic characteristics</italic> - The results of the multivariate analysis according to angiographic characteristics are summarized in <xref ref-type="table" rid="e06t6-body2">Table 6</xref>. Among the angiographic variables, calcification (OR = 0.13; 95% CI = 0.04 &#150; 0.43; p=0.0009) and irregular contour (OR = 0.15; 95% CI = 0.03 &#150; 0.72; p=0.02) were predictive of lower procedural success. Calcification (OR = 0.40; 95% CI = 0.20 &#150; 0.81; p=0.01) and total occlusion (OR = 0.44; 95% CI = 0.21 &#150; 0.91; p=0.03) were predictive of lower clinical success. Calcification (OR = 2.98; 95% CI = 1.48 &#150; 6.00; p=0.002); lesion lenght <underline>&gt;</underline> 10 mm (OR = 1.91; 95% CI = 1.02 &#150; 3.55; p=0.04) and total occlusion (OR = 2.43; 95% CI = 1.16 &#150; 5.10; p=0.02) were predictive of higher occurrence of complications.</p>
      <p>
        <bold>Discussion</bold>
      </p>
      <p>Since the introduction of percutaneous transluminal coronary angioplasty in 1977<sup>1</sup>, the utilization of percutaneous coronary interventions has spread rapidly. Because of the large number of procedures performed, in addition to morbidity and mortality risks, several studies have identified factors determining early and long-term outcomes<sup>7-21</sup>.</p>
      <p>We have verified that our results corroborate those of several studies published previously. Among the several series published, procedural success occurred from 95 to 99%, clinical success from 86 to 96%, and major complications from 3.5 to 13.2% (death from 0.4 to 3.5%; myocardial revascularization from 2.1 to 6.0%, and myocardial infarction from 0,9 to 6.8%)<sup>7,9-11,28-30</sup>. The variation observed between clinical success and major complications resulted mainly from a higher prevalence of patients with advanced age, left ventricular dysfunction and mainly cardiogenic shock, in addition to the study length and to the use of other percutaneous coronary intervention procedures associated to the stents. Cardiogenic shock is the major cause of mortality in patients hospitalized for acute myocardial infarction, ranging from 26 to 72%<sup>31,32</sup>. Sutton et al<sup>33</sup> analyzed retrospectively 113 patients with cardiogenic shock treated with percutaneous coronary interventions. Similar to our results, mortality was 51%. The authors have identified that age &gt; 70 years, previous myocardial infarction and failure of the thrombolytic treatment were independent variables related to in-hospital mortality.</p>
      <p><italic>Effect of the clinical variables</italic> - In the present study, patients with advanced age, diabetes mellitus, acute coronary syndromes, cardiogenic shock, and moderate to severe left ventricular dysfunction presented lower clinical success and higher percentage of in-hospital complications. Multivessel patients presented a higher percentage of complications. Restenotic lesions were a variable predictive of lower procedural success and of occurrence of in-hospital myocardial revascularization. Age, cardiogenic shock, systemic hypertension, moderate to severe left ventricular dysfunction and acute coronary syndromes were independent predictors of in-hospital mortality. O'Connor et al<sup>34</sup> identified age, cardiogenic shock, urgency/emergency procedures, left ventricular dysfunction, use of intra-aortic balloon and type C lesions as independent predictors of mortality. Renal dysfunction and heart failure were also predictors of death. These two latter variables and the use of intra-aortic balloon were not included in our analysis because data were not available for all patients. Resnic et al<sup>13</sup> identified similar factors predictive of mortality including cardiogenic shock, heart failure, tachycardia, renal failure, age <underline>&gt;</underline> 75 years, acute myocardial infarction and unstable angina. Block et al<sup>30</sup> analyzed the data of 8 different studies and identified a number of variables predictive of adverse events following percutaneous coronary interventions. The variables identified as predictive of myocardial infarction were: age, multivessel disease, acute ischemic syndromes, and restenotic lesion in 2 databases, and cardiogenic shock in 1. The variables identified as predictive of myocardial revascularization were: cardiogenic shock in 3 databases, left ventricular dysfunction in 2, acute ischemic syndrome in 1, and restenotic lesion in 1.</p>
      <p><italic>Effect of the angiographic variables, treated vessel and type of lesion</italic> - Of all angiographic characteristics included in the American College of Cardiology/ American Heart Association's classification, calcification, lesion lenght, total occlusion and irregular contour were identified as predictive of early outcomes. Other studies have sought to identify which angiographic characteristics, type of lesion, and vessel treated are related to the outcomes<sup>7,18</sup>.</p>
      <p>In our study, calcification was predictive of lower procedural success, lower clinical success, and higher occurrence of complications. Calcified lesions lead to a reduction in vessel distension, thus an inadequate stent expansion occurs, resulting in lower success and higher possibility of complications<sup>35,36</sup>. Ellis et al<sup>7</sup> studied 10,907 lesions and identified calcification as an independent predictor of ischemic complications.</p>
      <p>Lesions with irregular contours were predictive of lower procedural success whereas in Ellis et al<sup>7</sup>'s study an irregular contour was an independent predictor of ischemic complications.</p>
      <p>In our analysis, total occlusion was an independent variable predictive of lower clinical success and of higher occurrence of complications. Total occlusions include a broad spectrum that goes from recent occlusions secondary to atherosclerotic plaque rupture and vessel occlusion (97.6% of our case series) to chronic occlusions when the thrombus is organized (2.4% of all occlusions)<sup>37,38</sup>. In Ellis et al<sup>7</sup>'s analysis total occlusion lasting &lt; 3 months was the angiographic variable the most strongly correlated with the occurrence of in-hospital ischemic complications. In our study, unlike Ellis et al<sup>7</sup>'s results, calcification was the variable the most strongly correlated with both success and complications.</p>
      <p>Previous studies have demonstrated that the lesion lenght is directly related to the percentage of complications<sup>7,39,40</sup>, which corroborates our findings. Kornowski et al<sup>39</sup> demonstrated that major complications were more frequent in long lesions (3.4% versus 1.0%; p=0.04). In Ellis et al<sup>7</sup>'s study, lesion lenght between 10 and 20 mm was an independent predictor of ischemic complications.</p>
      <p>Lesions in the left main coronary and in the left anterior descending have been described as predictive of early complications<sup>15,16</sup>. Block et al<sup>30</sup> verified that lesions in the left main coronary were predictive of in-hospital mortality in 2 studies. In our study, lesions in the left main coronary were predictive of major complications, and no statistical significance was observed when we analyzed the other arteries.</p>
      <p>Several studies have demonstrated the predictive value of the ACC/AHA's classification when early outcomes following percutaneous coronary interventions are analysed<sup>15,30</sup>. However, the predictive value of the type of lesion has been lower than that previously observed because of the technical refinement including a high percentage of stent implantation and the use of platelet glycoprotein IIb/IIIa inhibitors. Krone et al<sup>18</sup> verified that ACC/AHA's classification presented a lower power of discrimination of early outcomes following percutaneous coronary interventions than the Society for Angiography and Interventions' (SCAI) classification, which was not used in our study. In our study, although complex lesions had presented lower clinical success and higher percentage of complications, we decided not to include the type of lesion in the multivariate model. This choice was based on the fact that the angiographic characteristics of the ACC/AHA's classification had been included in our model and, therefore, the inclusion of the variable type of lesion would be inadequate.</p>
      <p><italic>Limitations</italic> - This is an observational non-randomized study of patients consecutively treated with coronary stent implantation. We cannot generalize the findings; because our clinic is a reference center, the patients may have peculiarities that modified the outcomes and which we could not control. Some variables such as renal function and body mass index were not analyzed. Additionally, we did not assess blood glucose control in diabetics, a factor related to a lower occurrence of target lesion revascularization, re-hospitalization, and recurrent angina<sup>41</sup>. However, our experience represents the real world and not that of randomized clinical trials. Certain characteristics were observed in a small number; thus, they may have not reached a statistical significance due to the small sample size (type II error). Another limitation refers to the analysis of the lesions, which was performed by a single observer. We did not assess the degree of stenosis using quantitative coronary angiography (QCA), a method that is more precise than the visual assessment<sup>42,43</sup>, although we have already demonstrated a good correlation between QCA and visual estimate<sup>44</sup>. Likewise, the left ventricular function was estimated using visual assessment, and none of the imaging methods that estimate left ventricular function more accurately in addition to identifying the ventricular region affected<sup>45</sup> were used.</p>
      <p>
        <bold>Conclusion</bold>
      </p>
      <p>In the current phase of percutaneous coronary interventions with a significant use of stents, we have verified that clinical factors present a greater influence on early outcomes when compared to angiographic factors / type of lesion and vessel treated. Our analysis identified 3 clinical factors (cardiogenic shock, left ventricular dysfunction and age) and 2 angiographic factors (calcification and total occlusion) as independent predictors of early outcomes following stent implantation.</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>Correspond&#234;ncia:</bold>
          </label>
          <p> Ant&#244;nio Jos&#233; Neri-Souza</p>
          <p> Rua Tenente Fernando Tuy, 318/1701</p>
          <p> 41810-780 &#150; Salvador, BA - Brazil</p>
          <p> E-mail: </p>
          <p>
            <email xlink:href="nerisouza@cardiol.br">nerisouza@cardiol.br</email>
          </p>
        </fn>
      </p>
      <p>Received on 03/27/05</p>
      <p> Accepted on 11/11/05</p>
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  </sub-article>
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