Preoperative β-Blocker Use in Coronary Artery Bypass Grafting Surgery

IMPORTANCE: Use of preoperative β-blockers has been associated with a reduction in perioperative mortality for patients undergoing coronary artery bypass grafting (CABG) surgery in observational research studies, which led to the adoption of preoperative β-blocker therapy as a national quality standard. OBJECTIVE: To determine whether preoperative β-blocker use within 24 hours of CABG surgery is associated with reduced perioperative mortality in a contemporary sample of patients. DESIGN, SETTING, AND PARTICIPANTS: Retrospective analysis of the Society of Thoracic Surgeons National Adult Cardiac database for 1107 hospitals performing cardiac surgery in the United States from January 1, 2008, through December 31, 2012. Participants included 506,110 patients 18 years and older undergoing nonemergent CABG surgery who had not experienced a myocardial infarction in the prior 21 days or any other high-risk presenting symptom. We used logistic regression and propensity matching with a greedy 5-to-1 digit-matching algorithm to examine the association between β-blocker use and the main outcomes of interest. EXPOSURES: Preoperative β-blocker use. MAIN OUTCOMES AND MEASURES: Incidence of perioperative mortality, permanent stroke, prolonged ventilation, any reoperation, renal failure, deep sternal wound infection, and atrial fibrillation. RESULTS: Among the 506,110 patients undergoing CABG surgery who met the inclusion criteria, 86.24% received preoperative β-blockers within 24 hours of surgery. In propensity-matched analyses that included 138,542 patients, we found no significant difference between patients who did and did not receive preoperative β-blockers in rates of operative mortality (1.12% vs 1.17%; odds ratio OR, 0.96 95% CI, 0.87-1.06; P = .38), permanent stroke (0.97% vs 0.98%; OR, 0.99 95% CI, 0.89-1.10; P = .81), prolonged ventilation (7.01% vs 6.86%; OR, 1.02 95% CI, 0.98-1.07; P = .26), any reoperation (3.60% vs 3.69%; OR, 0.97 95% CI, 0.92-1.03; P = .35), renal failure (2.33% vs 2.24%; OR, 1.04 95% CI, 0.97-1.11; P = .30), and deep sternal wound infection (0.29% vs 0.34%; OR, 0.86 95% CI, 0.71-1.04; P = .12). However, patients who received preoperative β-blockers within 24 hours of surgery had higher rates of new-onset atrial fibrillation when compared with patients who did not (21.50% vs 20.10%; OR, 1.09 95% CI, 1.06-1.12; P < .001). Results of logistic regression analyses were broadly consistent. CONCLUSIONS AND RELEVANCE: Preoperative β-blocker use among patients undergoing nonemergent CABG surgery who have not had a recent myocardial infarction was not associated with improved perioperative outcomes.