Avaliação tardia de endopróteses coronarianas com sirolimus: comparação da tomografia computadorizada por múltiplos detectores com a angiografia quantitativa e o ultra-som intracoronariano

Abstract

To assess the performance of multidetector computed tomography in determining late clinical outcomes of patients undergoing sirolimus-eluting stent implantation. Thirty patients, successfully submitted to sirolimus-eluting stent implantation for more than six months, were selected to participate in the study. All underwent invasive angiography and intravascular ultrasound following CT angiography using iodinated contrast medium at a dose of 1.5 ml/kg. Mean proximal reference diameter was 3.01 +/- 0.31 mm by tomography and 3.14 +/- 0.31 mm by angiography (p = 0.04). When the left circumflex artery was excluded from the analysis, the difference between both examinations was no longer significant (tomography = 3.01 +/- 0.32 mm; angiography = 3.10 +/- 0.30 mm, p = 0.65). Mean distal reference diameter was 2.86 +/- 0.30 mm by tomography and 2.92 +/- 0.32 by angiography (p = 0.25). Mean in-stent minimal lumen diameter was 2.85 +/- 0.25 mm by tomography and 2.85 +/- 0.29 mm by angiography (p = 0.27). Mean minimal in-stent cross-sectional area was 7.19 +/- 1.47 mm(2) by tomography and 6.90 +/- 1.52 mm(2) by intravascular ultrasound (p = 0.36), but there was only a weak correlation between these measurements (r = 0.33). Computed tomography allows the qualitative assessment of sirolimus-eluting stents, accurate estimate of proximal and distal reference diameters of the target vessel, and in-stent minimal lumen diameter. Its correlation with measurements performed using intravascular ultrasound, however, is less strong.