Perioperative Protection of the Myocardium in Patients with Impaired Ventricular Function

Abstract

Seventeen patients with poor ventricular function and severe coronary artery obstruction were operated on employing hypothermic potassium cardioplegic solution for myocardial preservation. Preoperatively and postoperatively, serial hemodynamics, electrocardiograms (ECG), MB-CPK studies, and technetium pyrophosphate scans were obtained for all patients. All ECGs and scans were negative for perioperative infarction. Peak MB-CPK levels were 40 ± 25 units per liter. Two patients had MB-CPK levels suggestive of perioperative myocardial infarction. The preoperative cardiac index was 2.8 ±0.8 L/min/m 2 and remained the same in the perioperative period. Stroke work index and total peripheral resistance were within normal range and remained constant throughout the period of study. Three patients required epinephrine (0.5 μg per minute) during the first 6 hours postoperatively, and in 2 patients an intraaortic balloon was inserted prophylactically and removed on the second postoperative day. Good myocardial preservation can be achieved in patients with severe coronary artery obstruction and preexisting left ventricular dysfunction using hypothermic potassium cardioplegic solution.