The value of amiodarone for the treatment of unstable angina.
Amiodarone is a potent coronary vasodilator; it has alpha and beta receptor-antagonist activity and is well-known for its marked antiarrhythmic efficacy. This report describes the results of a randomized study of amiodarone in unstable angina. 40 patients (33 male, 7 female; mean age: 55) with unstable angina entered the study. They were randomized into two treatment groups. In group I (20 cases), amiodarone was the first drug applied (during the first 3 days; 1500 mg/24 hours IV + 200 mg orally every 8th hour; from day 4 onwards: 200 mg orally 3 times daily). If, after 8 hours following initiation of treatment, the symptoms were still present or recurred, nifedipine was added at a dose of 10 mg 4 times daily. In case of failure of the combined medical treatment, coronary angiography and, if needed, surgery was performed after 16 hours. In group II (20 cases), nifedipine was given as the first drug and at a dose of 10 mg every 6th hour. If, after 8 hours, this therapy failed, amiodarone was added according to the scheme previously described. In case of failure of the combined therapy, coronary angiography and surgery were performed. In group I, amiodarone was successful within 8 hours in 12 cases. None of the non-responders was improved by the addition of nifedipine. In group II, nifedipine was successful within 8 hours in 6 cases (p = 0.086). Among the 14 non-responders, amiodarone controlled the anginal episodes in 11 instances (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)