Preoperative use of beta blockers in patients without contraindications, particularly in those with an LVEF greater than 30%, can be effective in reduc- ing the risk of in-hospital mortality.609 611 (Level of Evidence: B) 2. Beta blockers can be effective in reducing the inci- dence of perioperative myocardial ischemia.612 615 (Level of Evidence: B) 3. Intravenous administration of beta blockers in clin- ically stable patients unable to take oral medications is reasonable in the early postoperative period.616 (Level of Evidence: B) Class IIb 1. The effectiveness of preoperative beta blockers in reducing inhospital mortality rate in patients with LVEF less than 30% is uncertain.609,617 (Level of Evidence: B) See Online Data Supplement 25 for additional data on beta blockers. 