Efficacy of slow-release nifedipine on myocardial ischemic episodes in variant angina pectoris.
To evaluate the efficacy of slow-release nifedipine (a single dose of 20 mg given at 10 P.M. or 2 doses of 20 mg at 10 P.M. and 6 A.M.) on ischemic episodes in patients with variant angina, a single-blind crossover study with ambulatory electrocardiographic monitoring was performed in 15 patients (13 men and 2 women, mean age 63 years). In all, there were 646 ischemic episodes detected with ambulatory electrocardiographic monitoring during the study period, and 618 episodes of them occurred during placebo periods with a circadian variation. Sixty-nine percent of the episodes in placebo periods were asymptomatic. The number of anginal attacks, nitroglycerin tablets taken, ST-segment elevation and the total ischemic duration significantly decreased during nifedipine therapy compared with results after the placebo therapy period, respectively (p less than 0.01 or 0.05). Twenty-eight ischemic episodes occurred during nifedipine therapy when the plasma level of nifedipine was low. Thus, asymptomatic ischemic episodes more frequently occur than symptomatic episodes and the administration of slow-release nifedipine is highly effective in suppressing not only symptomatic but also asymptomatic myocardial ischemia in patients with variant angina. The timing of the administration of slow-release nifedipine is an important factor in suppressing ischemic episodes.
Morikami
Y
Y
Division of Cardiology, Kumamoto University Medical School, Kumamoto City, Japan.
Yasue
H
H
D000368:Aged; D000369:Aged, 80 and over; D000788:Angina Pectoris, Variant / Q000188:drug therapy*; D002940:Circadian Rhythm; D003327:Coronary Disease / Q000503:physiopathology*; D003692:Delayed-Action Preparations; D004562:Electrocardiography / Q000187:drug effects; D015716:Electrocardiography, Ambulatory; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000503:physiopathology; D009543:Nifedipine / Q000008:administration & dosage / Q000097:blood / Q000627:therapeutic use*; D005996:Nitroglycerin / Q000008:administration & dosage / Q000627:therapeutic use; D010919:Placebos; D016037:Single-Blind Method; D013997:Time Factors
D003692:Delayed-Action Preparations; D010919:Placebos; D005996:Nitroglycerin; D009543:Nifedipine