Rationale for the choice of calcium antagonists in chronic stable angina. An objective double-blind placebo-controlled comparison of nifedipine and verapamil.

The effectiveness and safety of verapamil, nifedipine, and placebo in patients with chronic stable angina pectoris were evaluated and compared in two double-blind randomized crossover trials. In the first study, nifedipine (10 mg 3 times daily) was compared with placebo in 24 patients with chronic effort-related angina pectoris; no significant differences in exercise performance were observed with nifedipine compared with placebo. In the second study, the effects of verapamil (120 mg 3 times daily), nifedipine (20 mg 3 times daily), and placebo were compared in 32 patients with chronic stable angina using a double-blind crossover study design. Compared with placebo, both nifedipine and verapamil prolonged exercise duration (5.7 +/- 0.3 minutes with placebo, 7.9 +/- 0.5 minutes with nifedipine [p less than 0.001], and 10.0 +/- 0.7 minutes with verapamil [p less than 0.001]), but the improvement with verapamil was greater than that seen with nifedipine (p less than 0.01). Seven patients had increasing angina with nifedipine, none did with verapamil; the exacerbation of angina during nifedipine therapy appeared related to our observation that, compared with placebo, patients receiving nifedipine had higher heart rates, while patients receiving verapamil had slower heart rates. This study indicates that, at the doses used, verapamil was more effective and better tolerated than nifedipine in patients with chronic stable angina pectoris.

RCT Entities:   Population Interventions Outcomes