Comparative efficacy of nicardipine, a new calcium antagonist, versus nifedipine in effort stable angina.

The relative efficacy of nicardipine and nifedipine was examined in a double-blind randomized trial. We studied 12 patients with chronic effort angina who had reproducible chest pain and greater than or equal to 1.5 mm of ST-segment depression on treadmill exercise testing performed before and after 1-week control period of single-blind placebo administration. Subsequently over a 9-week period, nicardipine 20 mg or nifedipine 10 mg or an identical placebo four times a day, was administered in a randomized double-blind crossover fashion. Treadmill exercise testing was performed at the end of each 3-week period. Both nicardipine and nifedipine reduced the frequency of anginal attacks and trinitrate consumption. Compared with placebo both drugs caused a comparable increase of the total duration of exercise (p less than 0.05 placebo versus nicardipine; p less than 0.01 placebo versus nifedipine) and of the time to the onset of angina (p less than 0.05 placebo versus nicardipine; p less than 0.01 placebo versus nifedipine) and to the appearance of 1.5 mm ST depression (p less than 0.05 placebo versus nicardipine; p less than 0.01 placebo versus nifedipine). Moreover 4 patients no longer had angina with either drug and only 1 patient with placebo. Both drugs increased resting heart rate and reduced systolic blood pressure at resting (p less than 0.01) and submaximal exercise (p less than 0.01). Peak heart rate, systolic blood pressure and rate-pressure product were similar with placebo, nicardipine and nifedipine. No important side effects were observed with either drug. We conclude that nicardipine and nifedipine produce similar haemodynamic and clinical effects in patients with stable angina.