Effect of preoperative β-blockade on perioperative mortality in coronary surgery

Background. Many preoperative factors can influence perioperative mortality in cardiac surgery. Because the perioperative use of beta-blocking agents may reduce perioperative cardiac complications in non-cardiac surgery, we considered the possibility that beta-blocking agents could improve survival in coronary surgery patients. Methods. In a retrospective study on 1586 patients undergoing coronary bypass surgery, the relative risk of 30-day mortality was determined in relation to preoperative risk factors and medication. Factors included patient characteristics, pre-existing illness, specific cardiovascular risk factors, cardiac status and urgency of surgery. Treatment with beta-blocking agents, calcium antagonists, angiotensin-converting enzyme inhibitors, nitrates, anti-arrhythmic agents, diuretics and antithrombotic agents was taken into account. Results. Sex, age, chronic obstructive pulmonary disease, urgency and the preoperative use of diuretics and chronic beta-blocking therapy were found to be linked to mortality (P<0.05). Backward stepwise regression testing identified age, urgency and beta-blocking therapy as independent factors that could predict mortality. Conclusions. Increasing age and urgency of surgery are associated with greater mortality, whereas preoperative beta-blocking therapy is associated with less mortality. The characteristics of patients who received chronic beta-blockade did not differ significantly from those of patients who did not. The results suggest that chronic preoperative beta-blocker therapy reduces 30-day mortality in coronary surgery.