Long-term efficacy of high-dose diltiazem for chronic stable angina pectoris: 16-month serial studies with placebo controls

Michael A. Petru, Michael H. Crawford, Gemma T. Kennedy, K. Wray Amon, Robert A. O'Rourke

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12 Scopus citations


In order to assess the long-term efficacy of diltiazem for the treatment of angina pectoris, eight patients with chronic stable exertional angina who were previously entered into a 4-month randomized, double-blind placebo controlled study, were studied for an additional 12 months. The patients continued to take diltiazem, 360 mg/day, and underwent treadmill exercise testing after 10 and 16 months of therapy. A single-blind placebo week was introduced after 16 months and a treadmall test was porformed at the end of this week. Diltiazem therapy continued to augment exercise duration until 0.1 mV of ECG ST depression at 10 and 16 months as compared to the final pracebo period: 573 ± 133 (SD) seconds at 10 months; 565 ± 148 seconds at 16 months; vs 431 ± 151 seconds at final placebo (both p < 0.001). Also, the time to angina pectoris was prolonged on diltiazem by 181 seconds at 16 months (p < 0.01) and the total duration of exercise was increased by 101 seconds (p < 0.001) as compared to placebo. In addition, angina frequency decreased from 17 ± 11 attacks/week on placebo to 0.6 ± 0.6 attacks/week during diltiazem therapy at 16 months. Two of the eight paitents noted mild pedal edema, but no other adverse effects were experienced. Thus diltiazem, 360 mg/day, can be an effective single agent for the long-term treatment of chronic stable angina pectoris.

Original languageEnglish (US)
Pages (from-to)99-103
Number of pages5
JournalAmerican Heart Journal
Issue number1
Publication statusPublished - Jan 1985


ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine

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