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Propranolol-verapamil versus propranolol-nifedipine in severe angina pectoris of effort: a randomized, double-blind,
Abstract:
To compare a propranolol-verapamil with a propranolol-nifedipine combination in patients with severe angina of effort, 16 patients (11 men and 5 women, aged 56 +/- 8 years [mean +/- standard deviation]) with more than 5 episodes/week of angina and a positive exercise tolerance test despite propranolol (229 +/- 44 mg/day [range 180 to 360]) were maintained on this dose of propranolol and, in addition, received verapamil (360 mg/day) and nifedipine (60 mg/day) for 3 weeks each in a double-blind, randomized fashion. In comparison with propranolol alone, anginal frequency and nitroglycerin usage were reduced by propranolol-verapamil but not by propranolol-nifedipine. Exercise time (standard Bruce protocol) was similar for the 2 combinations (6.4 +/- 2.0 minutes with propranolol-verapamil, 6.6 +/- 2.1 minutes with propranolol-nifedipine, difference not significant), but the magnitude of ST-segment depression at peak exercise was less (p less than 0.05) during propranolol-verapamil (0.03 +/- 0.06 mV) than during propranolol alone (0.18 +/- 0.07 mV) and propranolol-nifedipine (0.08 +/- 0.07 mV). Left ventricular ejection fraction at rest was higher (p less than 0.05) with propranolol-nifedipine (0.62 +/- 0.10) than with propranolol-verapamil (0.58 +/- 0.10), but neither differed from ejection fraction at rest with propranolol alone (0.59 +/- 0.08). Ejection fraction at peak exercise was similar during all 3 periods. In 2 patients, verapamil caused weakness, lightheadedness, and severe sinus bradycardia (40 to 48 beats/min), and the dosage was reduced (blindly) to 240 mg/day, with the alleviation of bradycardia and associated symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)
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