Beta-blocker therapy in non-cardiac surgery.

Perioperative myocardial infarction is a major cause of complications and death among patients undergoing noncardiac surgery. 1 Annually in the United States, approximately 27 million patients are given anesthesia for surgical procedures; of these, approximately 50,000 patients have a perioperative myocardial infarction. 2 The pathophysiology of an acute perioperative myocardial infarction is probably the same as it is for infarction unrelated to surgery. 3 In patients with clinically significant coronary-artery stenosis, myocardial ischemia is induced either by a prolonged mismatch between oxygen demand and supply owing to the stress of surgery or as the result of a sudden rupture of a vulnerable plaque followed by thrombus formation and occlusion. Beta-blockers are commonly used to correct the imbalance between myocardial oxygen demand and supply. In the late 1980s, indications for beta-blocker therapy were hypertension and coronary artery disease, whereas heart failure and peripheral atherosclerotic disease were considered relative contraindications. However, subsequent research has led to the routine use of beta-blockers in patients with stable heart failure. Beta-blockers are also now recommended for patients with peripheral arterial disease who are undergoing vascular surgery. 4