Cardiac events occur in 1% to 5% of patients undergoing non-cardiac surgery. Myocardial ischemia and nonfatal myocardial infarction constitute the most significant risk factors for mortality and cardiovascular morbidity, in patients with coronary artery disease.
Perioperative b- blockade has been reported to reduce the risk of perioperative cardiac complications. Seven multicentre randomized trials have evaluated the impact of perioperative b-blocker administration on incidence of cardiovascular events.The Study of Perioperative Ischemia Research Group, the DECREASE and the BBSA trials focused on high risk patients for perioperative complications. The POBBLE, MaVS, and DIPOM trials did not target at patients with specific clinical risk factors, except DIPOM that included patients with diabetes. Finally, the POISE trial randomized patients with a wide variety of risk factors for perioperative cardiac complications. Interestingly, five meta-analyses reported a significant reduction in patients receiving b-blockers, with respect to perioperative myocardial ischemia and myocardial infarction.
In conclusion, consistent evidence demonstrated a reduction in cardiac mortality and myocardial infarction by perioperative b-blockade in patients with clinical risk factors, undergoing high-risk non-cardiac surgery. However, patients with extensive preoperative ischemia were at high risk of perioperative cardiac complications, despite b-blocker therapy. Conversely, perioperative b-blocker therapy did not reduce the incidence of cardiac complications in patients without clinical risk factors. While, the safety and effectiveness of perioperative b-blockers in intermediate-risk patients, still remain a debatable issue.