Variables predictive of successful medical therapy in patients with unstable angina: selection by multivariate analysis from clinical, electrocardiographic, and angiographic evaluations.

Although unstable angina can be initially controlled with medical therapy in most patients, there is a high incidence of subsequent death, myocardial infarction, or need for coronary bypass surgery to control symptoms. Identification at the time of presentation of the patient likely to do poorly on continued medical therapy would be useful in advising consideration of surgical therapy. Since coronary arterial spasm may have a significant role in the pathophysiology of unstable angina in some patients, the recently developed calcium channel antagonists may therefore be of particular benefit in the medical therapy of unstable angina. One hundred thirty-eight patients were entered into a randomized double-blind study of the efficacy of adding nifedipine to conventional treatment of unstable angina (nitrates and beta-blockers) and were followed for 18 months. Of these patients, 104 underwent coronary arteriography. A multivariate Cox's hazard function analysis was applied to variables selected from the histor...