The NIsoldipine in COronary artery disease in LEuven (NICOLE) study investigates (1) whether nisoldipine, a dihydropyridine calcium antagonist, reduces the progression of minor coronary arterial lesions in the long term, and (2) whether it reduces the restenosis rate after successful percutaneous transluminal coronary angioplasty (PTCA). The NICOLE study is a single-center, randomized, double-blind trial in 826 patients, who underwent a successful PTCA. Nisoldipine 40 mg coat-core or placebo was started the morning after the procedure and continued for 3 years. All coronary arterial segments were measured on preprocedural angiogram and on the second follow-up angiogram at 3 years. On the first follow-up angiogram at 6 months only the dilated segments were measured. Although the study is still ongoing until the primary end point is reached, we report in this study the angiographic restenosis data as well as the clinical events observed at 6-month follow-up. The per-protocol population consisted of 646 patients. Restenosis, defined as a > or =50% loss of the initial gain (National Heart, Lung, and Blood Institute criterion IV) occurred in 49% and 55% of the 308 nisoldipine-treated and the 338 placebo-treated patients, respectively (p = NS). At follow-up, the rates of death and myocardial infarction were low and similar in both groups, but in the nisoldipine group, less patients required early coronary angiography (18% vs 26%, p = 0.006) and subsequent revascularization procedures (32% vs 41%, p = 0.057). Thus, nisoldipine did not significantly reduce the angiographic restenosis rate after PTCA, but reduced the number of repeat revascularization procedures, which may be due to its antianginal action.