Comparison of combination nifedipine-propranolol and diltiazem-propranolol with high dose diltiazem monotherapy for stable angina pectoris

Patients with chronic stable angina are frequently treated with calcium antagonist-beta-blocker combination drug therapy. However, there is a paucity of data comparing such combination therapies with each other and with high dose calcium antagonist monotherapy. Nineteen patients with chronic stable angina pectoris were studied using a prospective, randomized, Latin-square crossover protocol in an effort to determine the differential effects of nifedipine-propranolol combination therapy, diltiazem-propranolol combination therapy and high dose diltiazem monotherapy on exercise treadmill performance. All patients performed exercise tolerance tests after 4 weeks on each of the 3 therapeutic regimens. Both nifedipine (mean daily dose 70 +/- 23 mg) and diltiazem (mean daily dose 237 +/- 12 mg) in combination with propranolol (mean daily dose 146 +/- 58 mg) resulted in significant increases in total exercise time, time to onset of angina and time to maximal ST-segment depression compared with high dose diltiazem (mean daily dose 347 +/- 38 mg) monotherapy (p less than or equal to 0.001). Double-product at rest and the increase observed from rest to the end of stage 1 were significantly decreased during nifedipine-propranolol and diltiazem-propranolol combination therapy compared with high dose diltiazem monotherapy (p less than or equal to 0.001). In patients with chronic stable angina both nifedipine-propranolol and diltiazem-propranolol combination therapy resulted in significantly greater improvement in exercise performance compared with high dose diltiazem monotherapy.