Factors predictive of cardiac events and restenosis after sirolimus‐eluting stent implantation in small coronary arteries

Abstract

Predictors of cardiac events and restenosis after sirolimus-eluting stent (SES) implantation in small coronary arteries were evaluated. Although SES implantation has markedly reduced the risk of restenosis, small vessel disease remains a major cause of SES failure. We prospectively investigated the factors predictive of cardiac events and restenosis in 1,092 consecutive patients who received SES implantation for 1,269 lesions in small coronary arteries (< or = 2.8 mm). Follow-up angiography at 6 months was performed in 751 patients with 889 lesions (follow-up rate 70.3%). Restenosis (diameter stenosis > or = 50%) was angiographically documented in 65 patients with 77 lesions (8.7%): 55 focal (71.4%), 8 diffuse (10.4%), 2 diffuse proliferative (2.6%), and 12 total (15.6%). Lesion length, stent length, reference artery size, and in-stent restenotic lesions were univariate predictors of restenosis. By multivariate analysis, lesion length (OR 1.04; 95% CI 1.02-1.05; P < 0.001) and in-stent restenotic lesions (OR 3.38; 95% CI 1.80-6.35; P < 0.001) were significant independent predictors of restenosis. During follow-up (23.2 +/- 7.9 months), there were 17 deaths (5 cardiac and 12 noncardiac), 5 nonfatal Q-wave myocardial infarctions, and 42 target lesion revascularizations. The cumulative probability of survival without major adverse cardiac events (MACE) was (96.6 +/- 0.6)% at 1 year and (95.1 +/- 0.7)% at 2 years. In multivariate analysis, lesion length (HR 1.04; 95% CI 1.01-1.07; P = 0.004) and in-stent restenotic lesions (HR 3.29; 95% CI 1.58-6.86; P = 0.001) were independently related to MACE. SES implantation in small coronary arteries is safe and effective, with lesion length having a major impact on restenosis and MACE.