Desempenho diagnóstico da reserva de fluxo fracionado por tomografia na detecção de estenoses coronárias hemodinamicamente significativas / Fractional flow reserve by tomography diagnostic performance in the detection of coronary stenoses hemodynamically significant

BACKGROUND: Coronary computed tomography angiography is a noninvasive anatomic test for the diagnosis of coronary artery disease. The coronary fractional flow reserve is the gold standard method to determine if coronary stenosis is hemodynamically significant but requires an invasive procedure. Fractional flow reserve measurement by tomography is a new method to determine the hemodynamic significance of coronary luminal reduction. OBJECTIVE: To compare the accuracy of the invasive fractional flow reserve with the fractional flow reserve measurement by tomography. METHOD: Patients submitted to invasive coronary computed tomography angiography and fractional flow reserve were included in the study. Flow-restricted stenosis was defined by fractional flow reserve measurement by tomography and fractional flow reserve ≤ 0.8, and anatomically significant coronary artery disease was defined as stenosis ≥ 50%. Diagnostic performance of fractional flow reserve measurement by tomography and stenosis by coronary computed tomography angiography was accessed with invasive fractional flow reserve as the gold standard. RESULTS: Among the patients, 33% had fractional flow reserve ≤0.8. There was no significant difference between the fractional flow reserve measurement by tomography and fractional flow reserve averages (0.87 versus 0.84; p = 0.4). The correlation between the values of the methods was r = 0.77, and concordance was moderate (k = 0.54). When fractional flow reserve ≤ 0.75 was analyzed, the concordance between the methods was absolute. The sensitivity, specificity, positive predictive value and negative predictive value of fractional flow reserve measurement by tomography were, respectively, 50%, 100%, 100% and 75%, for the threshold of 0.8. The mean difference between fractional flow reserve and fractional flow reserve measurement by tomography was -0.033 (95%CI -0.072-0.007), with concordance limits between -0.176 and -0.1111. CONCLUSION: Fractional flow reserve measurement by tomography is a new method with high diagnostic performance in the detection of hemodynamically significant coronary stenoses and significantly elevates the specificity of the isolated coronary computed tomography angiography.

FUNDAMENTO: A angiotomografia de coronárias é um teste anatômico não invasivo para diagnóstico de doença arterial coronariana. A reserva de fluxo fracionado coronariano é o método padrão-ouro para determinar se a estenose coronariana é hemodinamicamente significativa e requer procedimento invasivo. A mensuração da reserva de fluxo fracionado por tomografia é um novo método para determinar a significância hemodinâmica da redução luminal coronária. OBJETIVO: Comparar a acurácia da reserva de fluxo fracionado invasiva com a reserva de fluxo fracionado por tomografia. MÉTODO: Pacientes submetidos à angiotomografia de coronárias e à reserva de fluxo fracionado invasiva foram incluídos neste estudo. Estenose com limitação de fluxo foi definida por reserva de fluxo fracionado por tomografia e reserva de fluxo fracionado ≤ 0,8. Doença arterial coronariana anatomicamente significativa foi definida por estenose ≥ 50%. O desempenho da reserva de fluxo fracionado por tomografia e da estenose pela angiotomografia de coronárias foi acessado com a reserva de fluxo fracionado invasiva como padrão-ouro. RESULTADOS: Dentre os pacientes, 33% tinham reserva de fluxo fracionado ≤ 0,8. Não houve diferença significativa entre as médias de reserva de fluxo fracionado por tomografia e reserva de fluxo fracionado (0,87 versus 0,84; p=0,4). A correlação entre os valores dos métodos foi r = 0,77, com concordância moderada (k=0,54). Quando analisada a reserva de fluxo fracionado ≤ 0,75, a concordância entre os métodos foi absoluta. Sensibilidade, especificidade, valor preditivo positivo e negativo da reserva de fluxo fracionado por tomografia foram, respectivamente, 50%, 100%, 100% e 75%, para o limiar de 0,8. A média da diferença entre reserva de fluxo fracionado e reserva de fluxo fracionado por tomografia foi de -0,033 (IC95% -0,072-0,007), com limites de concordância entre -0,176 e -0,111. CONCLUSÃO: A reserva de fluxo fracionado por tomografia é um novo método, com alto desempenho diagnóstico na detecção de estenoses coronárias hemodinamicamente significativas, e eleva significativamente a especificidade da angiotomografia de coronárias isolada.

Reduced Progression of Cardiac Allograft Vasculopathy with Routine Use of Induction Therapy with Basiliximab / Redução da Progressão da Doença Vascular do Enxerto Cardíaco com o Uso Rotineiro da Terapia de Indução com Basiliximab

AbstractIntroduction:Cardiac allograft vasculopathy (CAV) is a major limitation for long-term survival of patients undergoing heart transplantation (HT). Some immunosuppressants can reduce the risk of CAV.Objectives:The primary objective was to evaluate the variation in the volumetric growth of the intimal layer measured by intracoronary ultrasound (IVUS) after 1 year in patients who received basiliximab compared with that in a control group.Methods:Thirteen patients treated at a single center between 2007 and 2009 were analyzed retrospectively. Evaluations were performed with IVUS, measuring the volume of a coronary segment within the first 30 days and 1 year after HT. Vasculopathy was characterized by the volume of the intima of the vessel.Results:Thirteen patients included (7 in the basiliximab group and 6 in the control group). On IVUS assessment, the control group was found to have greater vessel volume (120–185.43 mm3 vs. 127.77–131.32 mm3; p = 0.051). Intimal layer growth (i.e., CAV) was also higher in the control group (27.30–49.15 mm3 [∆80%] vs. 20.23–26.69 mm3[∆33%]; p = 0.015). Univariate regression analysis revealed that plaque volume and prior atherosclerosis of the donor were not related to intima growth (r = 0.15, p = 0.96), whereas positive remodeling was directly proportional to the volumetric growth of the intima (r = 0.85, p < 0.001).Conclusion:Routine induction therapy with basiliximab was associated with reduced growth of the intima of the vessel during the first year after HT.

ResumoFundamento:A doença vascular do enxerto (DVE) constitui uma grande limitação de sobrevida a longo prazo de pacientes submetidos a transplante cardíaco (TxC). Alguns imunossupressores diminuem o aparecimento da DVE.Objetivos:O principal objetivo foi avaliar, através de ultrassonografia intracoronária (USIC), a variação do crescimento volumétrico da camada íntima e comparar, após um ano, o grupo que recebeu basiliximab com um grupo de controle.Métodos:Treze pacientes de um único centro foram analisados retrospectivamente de 2007 a 2009. As análises foram feitas através de USIC, medindo-se o volume de um segmento coronariano nos primeiros 30 dias e um ano após o TxC. A vasculopatia foi caracterizada pelo volume da camada íntima do vaso.Resultados:O estudo incluiu 13 pacientes (7 no grupo com o basiliximab e 6 no grupo de controle). A análise por USIC revelou que o grupo de controle apresentou maior crescimento volumétrico do vaso (131,32 a 127,77 mm3 x 120 a 185,43 mm3 p = 0,051). O crescimento da camada íntima (CCI) também foi maior no grupo de controle [Basiliximab: 20,23 a 26,69 mm3 (∆ 33%); Controle: 27,30 a 49,15 mm3(∆ 80% p = 0,015)]. De acordo com a regressão univariada, o volume da placa aterosclerótica prévia do doador não teve relação com o crescimento da íntima (r = 0,15, p = 0,96), enquanto que o remodelamento positivo do vaso foi diretamente proporcional ao crescimento da íntima (r = 0,85, p < 0,001).Conclusão:A terapia de indução de rotina com basiliximab está associada à redução do crescimento da camada íntima do vaso no primeiro ano após o transplante cardíaco.

Reduced progression of cardiac allograft vasculopathy with routine use of induction therapy with basiliximab.

INTRODUCTION: Cardiac allograft vasculopathy (CAV) is a major limitation for long-term survival of patients undergoing heart transplantation (HT). Some immunosuppressants can reduce the risk of CAV. OBJECTIVES: The primary objective was to evaluate the variation in the volumetric growth of the intimal layer measured by intracoronary ultrasound (IVUS) after 1 year in patients who received basiliximab compared with that in a control group. METHODS: Thirteen patients treated at a single center between 2007 and 2009 were analyzed retrospectively. Evaluations were performed with IVUS, measuring the volume of a coronary segment within the first 30 days and 1 year after HT. Vasculopathy was characterized by the volume of the intima of the vessel. RESULTS: Thirteen patients included (7 in the basiliximab group and 6 in the control group). On IVUS assessment, the control group was found to have greater vessel volume (120-185.43 mm3 vs. 127.77-131.32 mm3; p = 0.051). Intimal layer growth (i.e., CAV) was also higher in the control group (27.30-49.15 mm3 [∆80%] vs. 20.23-26.69 mm3[∆33%]; p = 0.015). Univariate regression analysis revealed that plaque volume and prior atherosclerosis of the donor were not related to intima growth (r = 0.15, p = 0.96), whereas positive remodeling was directly proportional to the volumetric growth of the intima (r = 0.85, p < 0.001). CONCLUSION: Routine induction therapy with basiliximab was associated with reduced growth of the intima of the vessel during the first year after HT.