Unstable angina: The case for operation

Abstract

From July 1975 through September 1977, surgical revascularization was performed in 95 consecutive patients with unstable angina, 53 at high risk (defined as in-hospital pain at rest with reversible ischemic electrocardiographic changes) and 42 at low risk (defined as pain at rest remitting upon hospitalization). Historical, electrocardiographic and cardiac catheterization data were similar in both groups; however, patients at high risk required large doses of propranolol, and one patient needed additional intraaortic counterpulsation for preoperative stabilization of ischemia. Proximal left anterior descending (79 patients) and left main (15 patients) coronary artery disease with abnormal ventricular function characterized both groups of patients with unstable angina. Revascularization (2.5 grafts/patient) was performed with hypothermia and intermittent ischemic arrest. Complications included one death and three perioperative infarctions. No patient needed inotropic support. No late deaths occurred in a follow-up period of up to 30 months. The data indicate that (1) “prophylactic” preoperative intraaortic balloon counterpulsation in patients with unstable angina, although advocated by some surgeons, is unnecessary; (2) the very small incidence of complications when unstable angina—particularly high risk unstable angina—is managed as outlined strongly suggests that surgical revascularization is definitive therapy; and (3) the therapeutic implications of large scale controlled studies of medical versus surgical therapy for unstable angina, which include results achieved 3 or 4 years ago and describe significantly higher rates of mortality and infarction than those reported here and by others, may not be pertinent to therapeutic decisions made today.