Left ventricular subendocardial necrosis.

The hearts of as many as 90% of patients who die after open-heart operations have left ventricular subendocardial necrosis. This form of myocardial infarction depresses myocardial performance postoperatively and may result in late myocardial fibrosis. It occurs without anatomical obstruction of the coronary arteries and is caused by a discrepancy between subendocardial oxygen supply and demand during the perioperative period. This review of subendocardial necrosis summarizes the author's current understanding of: (1) why the subendocardium is especially vulnerable to this injury; (2) how to predict which patients are most susceptible to it; (3) how interventions before, during, and after extracorporeal circulation can either contribute to it, minimize its severity, or prevent it; and (4) where future study of this problem should be directed.