Atenolol with and without nifedipine in the treatment of angina pectoris. Preliminary report.

Atenolol and nifedipine have been shown to be effective single agents in angina pectoris, but reports suggest that additional benefits may be conferred by combining the 2 drugs. Therefore, to establish that the combination regimen was at least as effective as either atenolol or nifedipine alone, a multicentre study was performed to compare the treatment regimens in 94 patients with characteristic chest pain compatible with a diagnosis of stable angina pectoris which was provoked by effort and relieved by glyceryl trinitrate. After 4 weeks on atenolol 50 mg twice daily, the patients were randomised to receive, in a double-blind crossover fashion, atenolol 50 mg twice daily either with or without sustained release nifedipine 20 mg twice daily for 4 weeks. Compared with entry, all treatments apparently reduced the number of anginal attacks per week and the number of glyceryl trinitrate tablets taken. It was notable that blood pressure in patients during the study was normal. Treatment with atenolol or the combination appeared to improve exercise tests measured by time to onset of pain, time to greater than or equal to 1mm ST segment depression and duration. The ST segment depression was substantially lower on the fixed combination compared with atenolol alone; ST segment depression during exercise was recorded in 82% of patients after atenolol and 75% after the combination, compared with 100% on entry. There was a substantial improvement in the number of patients rendered pain free: 29% on atenolol and 42% on combination. There was little difference between treatments in terms of adverse effects.(ABSTRACT TRUNCATED AT 250 WORDS)