Coronary microvascular endothelial function deteriorates late (12 months) after sirolimus-eluting stent implantation

SummaryBackgroundCoronary flow velocity reserve (CFVR) may reflect coronary microvascular endothelial function in the absence of significant epicardial coronary artery stenosis. The purpose of this study was to evaluate coronary microvascular endothelial function late (6 and 12 months) after sirolimus-eluting stent (SES) implantation using transthoracic Doppler echocardiography.Methods and resultsA total of 21 lesions from 21 patients with significant left anterior descending artery stenosis who underwent percutaneous coronary intervention (PCI) with SES were enrolled and studied. As a control group, 10 patients who were treated with bare metal stent (BMS) were also studied. CFVR was measured at 6 and 12 months after PCI. Coronary angiography was also performed at 6 and 12 months (SES only) after stenting. Between 6 and 12 months after SES implantation, there was no significant difference in angiographical diameter stenosis. On the other hand, CFVR significantly decreased between 6 and 12 months in the SES group (2.5 ± 0.5 vs. 2.2 ± 0.5, p < 0.01), but not in the BMS group (2.3 ± 0.4 vs. 2.5 ± 0.3, p = 0.1).ConclusionsCoronary microvascular endothelial function may deteriorate between 6 and 12 months after SES implantation.