Coronary stent restenosis in patients treated with cilostazol

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.