Outcome studies in perioperative ischemia, infarction, ventricular dysfunction, and congestive heart failure

Summary Anesthesiologists are commonly confronted with patients at risk for perioperative cardiovascular morbidity. A large number of studies performed over the last two decades have consistently confirmed the value of recent myocardial infarction (less than 6 months of age) and current congestive heart failure as predictors of adverse perioperative cardiac outcome. The assessment of preoperative left ventricular function and monitoring for preoperative silent ischemia have identified an abnormal left ventricular ejection fraction and either electrocardiographic or radionuclide scintigraphic evidence of ischemia as markers of high cardiac risk in certain subsets of patients. The optimal test or tests to detect abnormal pump function or myocardial perfusion preoperatively have not been identified, but such testing is becoming important as an element of the comprehensive management of patients with cardiovascular disease who require operation and anesthesia. Intraoperative ischemia, a relatively common event, appears to be a good predictor of perioperative events even though most patients with intraoperative ischemia do not progress to infarction. Most data indicate that the choice of anesthetic does not critically influence cardiovascular outcome after cardiac surgery. However, data are accumulating that suggest that certain high-risk subsets of patients undergoing noncardiac procedures (such as vascular surgery) may have improved outcome when epidural anesthesia and analgesia are employed. The frequency and prognostic importance of postoperative ischemia are being defined. Preliminary data indicate that postoperative ischemia is common and as important as intraoperative events. If postoperative ischemic changes are confirmed to be predictive of adverse cardiac events, this may indicate the need to provide a means for early detection and aggressive interventional therapy in the postoperative period to improve outcome. Early and aggressive treatment of increased heart rate has been defined as a critical aspect of intraoperative anesthetic management; this role of the anesthesiologist/intensivist may be extended into the postoperative period when the relationship of postoperative physiologic changes, such as tachycardia, to postoperative cardiac morbidity, such as ischemia and infarction, are better defined. The potential importance of postoperative anesthetic management also has been suggested, both in the setting of cardiac surgery as well as in high-risk noncardiac surgery. Further studies are necessary to confirm that postoperative anesthetic management can affect outcome and to uncover potentially important associations between anesthetic management and mechanisms of perioperative cardiac morbidity. These associations may involve subtle interactions of anesthetic management on factors such as the stress response and coagulation system, especially in the postoperative period. Future studies that examine determinants of outcome must place their findings in the clinical context. Anesthesiologists should be active participants in these studies because the consideration of intraoperative management and postoperative intensive care unit and pain therapy interface with other determinants of outcome in these high-risk patients.