Coronary Stent Restenosis in Patients Treated With Cilostazol

Abstract

Background— Restenosis after implantation of coronary artery stents remains a significant clinical problem. We undertook a randomized, double-blind, placebo-controlled trial to determine whether cilostazol, a drug that suppresses intimal proliferation, would reduce renarrowing in patients after stent implantation in native coronary arteries. Methods and Results— We assigned 705 patients who had successful coronary stent implantation to receive, in addition to aspirin, cilostazol 100 mg BID or placebo for 6 months; clopidogrel 75 mg daily was administered to all patients for 30 days. Restenosis was determined by quantitative coronary angiography at 6 months. The minimal luminal diameter at 6 months for cilostazol-treated patients was 1.77 mm for the analysis segment (stent plus 5-mm borders) compared with 1.62 mm in the placebo group ( P =0.01). Restenosis, defined as ≥50% narrowing, occurred in 22.0% of patients in the cilostazol group and in 34.5% of the placebo group ( P =0.002), a 36% relative risk reduction. Restenosis was significantly lower in cilostazol-treated diabetics (17.7% versus 37.7%, P =0.01) and in those with small vessels (23.6% versus 35.2%, P =0.02), long lesions (29.9% versus 46.6%, P =0.04), and left anterior descending coronary artery site (19.3% versus 39.8%, P =0.001). There was no difference in bleeding, rehospitalization, target-vessel revascularization, myocardial infarction, or death. Conclusions— Treatment with the drug cilostazol resulted in a significantly larger minimal luminal diameter and a significantly lower binary restenosis rate compared with placebo-treated patients. These favorable effects were apparent in patients at high risk for restenosis.