The rational use of beta-blocker in the perioperative patient undergoing non-cardiac surgery

Cardiac complications are a major cause of morbidity and mortality after non-cardiac surgery, whose incidence varies according to patient risk stratification and type of patient cohorts investigated. Perioperative myocardial injury may be triggered by different conditions occurring in the perioperative phase, and patient risk factors represent a favorable milieu for triggers to act. The majority of postoperative myocardial ischemia in high-risk patients tends to develop very early on the day of surgery, starting at the end of surgery and during emergence from anesthesia, or on the first postoperative day. Most of postoperative episodes of myocardial ischemia are silent, and show ST-segment depression rather than elevation. Preventive measures are aimed at improving perioperative cardiac outcome, but their identification and application in clinical practice require understanding of the pathophysiology of myocardial ischemia and infarction in non-cardiac surgery patients. Among the protective strategies, beta-blocking agents are the most investigated since 1996, when data from atenolol administration showed a protective effect against myocardial ischemia and infarction in non-cardiac surgery. Since then several clinical studies have reported encouraging results, but conflicting data on possible serious side effects have recently raised concern and doubts about routine administration of beta-blockers in patients at risk undergoing non-cardiac surgery. The aim of this manuscript is to address the main mechanisms responsible for myocardial ischemia in the perioperative phase of non-cardiac surgery and, by going through the recent literature and taking into consideration the very recent European and American recommendations, to provide a pathophysiological approach to the use of beta-blockers in such scenario.