title: Effect of diltiazem and propranolol on myocardial ischaemia during unrestricted daily life in patients with effort-induced chronic stable angina pectoris.
abstract: To examine the effect of diltiazem 60 mg thrice daily and propranolol 80 mg thrice daily on myocardial ischaemia during unrestricted daily life, we have studied 14 patients with established effort-induced chronic stable angina pectoris in a double-blind crossover study. Ambulatory electrocardiographic monitoring was performed using frequency modulated (FM) tape recorder after 2 weeks of placebo therapy and at the end of each 4 week treatment period for a minimum of 24 h. The mean (+/- SEM) number of episodes of ST-segment depression greater than 1 mm during placebo treatment were 97 +/- 28, and these fell to 54 +/- 27 during diltiazem treatment (p less than 0.05) and to 12 +/- 6 during propranolol treatment (p less than 0.02). The maximal depth of ST-segment depression in 24 h, which indicates the severity of the episode, was 3.3 +/- 0.4 mm during placebo, 2.5 +/- 0.2 mm during diltiazem (p less than 0.05), and 1.6 +/- 0.5 mm during propranolol (p less than 0.01). Both diltiazem and propranolol treatment produced significant reduction in the total area of ST-segment depression observed during 24 h. A uniform reduction in the mean heart rate during the 24 h was observed during propranolol therapy and not during diltiazem therapy. Both diltiazem and propranolol treatment improved indices of myocardial ischaemia during daily normal unrestricted life, as measured by ambulatory ST-segment monitoring in patients with established chronic stable angina pectoris. Their differing effects on heart rate suggest that they act by different mechanisms.
mesh_terms: D000368:Aged; D003327:Coronary Disease / Q000188:drug therapy* / Q000503:physiopathology; D004110:Diltiazem / Q000494:pharmacology / Q000627:therapeutic use*; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D011433:Propranolol / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D011433:Propranolol; D004110:Diltiazem