Results and patterns of perioperative myocardial infarction

Myocardial injury during a variety of cardiac surgical operations was determined in 57 patients by serial electrocardiograms (ECG's), serial determinations of serum creatine phosphokinase (CPK), and perioperative and postoperative technetium-99m stannous pyrophosphate (PYP) scans. ECG evidence of injury developed in four patients, whereas positive localized injury by PYP scan developed in ten. Twenty-one patients had elevated CPK enzymes postoperatively. The localization of injury by PYP scan correlated with ECG evidence of infarction in only one of four patients. Localized left ventricular injury by PYP scan without new Q waves on the ECG was common (5/12) in patients undergoing aortic valve replacement with perfusion of the coronary arteries. The injury in patients with congenital heart disease occurred at sites of ventricular incision or suggested possible air embolization of the coronary arteries. Perioperative infarction is frequently segmental and nontransmural and occurs in patients with coronary, valvular, and congenital heart disease.