Pre-Operative Risk Assessment and Risk Reduction Before Surgery
Perioperative myocardial infarctions are the predominant cause of morbidity and mortality in patients undergoing noncardiac surgery. The pathophysiology of perioperative myocardial infarction is complex. Prolonged myocardial ischemia due to the stress of surgery in the presence of a hemodynamically significant coronary lesion, leading to subendocardial ischemia, and acute coronary artery occlusion after plaque rupture and thrombus formation contribute equally to these devastating events. Perioperative management aims at optimizing the patient's condition by identification and modification of underlying cardiac risk factors and diseases. During recent decades there has been a shift from the assessment and treatment of the underlying culprit coronary lesion toward a systemic medical therapy aiming at prevention of myocardial oxygen supply demand mismatch and coronary plaque stabilization. Beta-blockers, statins, and aspirin are widely used in this setting. The role of prophylactic coronary revascularization has been restricted to the same indications as the nonoperative setting. Therefore pre-operative cardiac testing is recommended only if test results will change perioperative management. In addition to the limited perioperative period, physicians should benefit from this opportunity to initiate lifestyle changes and medical therapy to lessen the impact of cardiac risk factors, as patients should live long enough after the operation to enjoy the benefits of surgery.