Changing indications for the surgical treatment of unstable angina.

From 1970 to 1977, 127 patients were operated on for unstable angina. On the basis of response to intensive medical therapy, patients were classified into a medically controlled, semielective surgery group (54 patients) and a medically uncontrolled, emergent/urgent surgical group (73 patients). There were five operative deaths. 1/54 in the medically controlled group (1.8%) and 4/73 (5%) in the medically uncontrolled group; 4/5 operative deaths occured with left main coronary stenosis. There were five late deaths during a follow-up period of 12 to 84 months, 37.5 with an actuarial survival of 83.5%. If patients with unstable angina can be medically controlled, operation can be delayed and the operative long-term survival is similar to that of elective coronary bypass. Patients who cannot be controlled medically, particularly those with left main coronary lesions, should be operated on urgently with selective use of preoperative balloon support.