Natural history and prognosis of unstable angina.

One hundred patients admitted to coronary care with unstable angina were followed for a period of 1 year. A conservative approach to treatment was adopted. Routine beta blockers, calcium antagonists, and anticoagulants were not employed. Patients with persistent pain following admission were treated with nitrates only and with symptomatic treatment. One death and nine nonfatal infarctions occurred within the first 28 days after admission. A total of eight deaths, 14 nonfatal infarctions, and three readmissions for unstable angina occurred during the follow-up period of 1 year. Of the various initial factors studied, persistence of pain and the magnitude and extent of ECG ST-T changes were the only predictors of an unfavorable outcome. Non-smokers and those with a previous history of angina on effort had a significantly higher incidence of persistence of pain. The withdrawal of beta blockers on admission and the late administration of beta blockers to those with persistent pain did not appear to influence outcome.