2. American College of Cardiology & American Heart Association Recommendations

Several recent trials have examined the impact of medical therapy begun just before surgery on reducing cardiac events. Two randomized, placebo-controlled trials of beta-blocker administration have been performed (13,14,55,56). One trial demonstrated reduced perioperative cardiac events, and the other demonstrated improved 6-month survival with perioperative beta-blocker usage. Several trials have evaluated the utility of alpha-2 agonists, demonstrating reduced cardiac event rates in the subset of patients with known CAD undergoing vascular surgery (57-60).

There are still very few randomized trials of medical therapy before noncardiac surgery to prevent perioperative cardiac complications, and they do not provide enough data from which to draw firm conclusions or recommendations. Most are insufficiently powered to address the effect on outcome of MI or cardiac death, and they rely on the surrogate end point of ECG ischemia to show effect. Current studies, however, suggest that appropriately administered beta-blockers reduce perioperative ischemia and may reduce the risk of MI and death in high-risk patients. When possible, beta-blockers should be started days or weeks before elective surgery, with the dose titrated to achieve a resting heart rate between 50 and 60 beats per minute. Perioperative treatment with alpha-2 agonists may have similar effects on myocardial ischemia, infarction, and cardiac death. Clearly, this is an area in which further research would be valuable.