Patient outcomes in the assessment of myocardial injury following cardiac surgery.

In the absence of online methods for the intraoperative assessment of the adequacy of myocardial protection, patient outcomes remain the gold standard for determining whether a patient has sustained injury in the course of a cardiac operation. Properly risk-adjusted 30-day postoperative mortality and myocardial infarction are the most definitive indicators of perioperative injury. The definition and clinical assessment of irreversible ischemic myocardial injury continues to be problematic postoperatively. In most instances, deterioration in postoperative cardiac function and performance is indicative of intraoperative injury. Late postoperative mortality and long-term survival may be affected by intraoperative myocardial injury. Likewise, long-term graft patency may be affected by intraoperative injury to the conduit vascular endothelium. Proper assessment of outcomes, although it may not change the intraoperative course of an operation, can be useful in the comparative assessment of the efficacy of various operations, methods, and techniques.