Preoperative Use of Oral Beta-Adrenergic Blocking Agents and the Incidence of New-Onset Atrial Fibrillation After Cardiac Surgery. A Systematic Review and Meta-Analysis

Background: Current epidemiological data suggests that postoperative atrial fibrillation or atrial flutter (POAF) causes significant morbidity and mortality after cardiac surgery. The literature for prophylactic management of POAF is limited, resulting in the lack of clear guidelines on management recommendations.

Aim: To examine the efficacy of prophylactic rate control agents in reducing the incidence of new-onset POAF in patients undergoing elective cardiac surgery.

Methods: Cochrane Central Register of Controlled Trials (CENTRAL), Embase, and Medline were systematically searched for blinded randomised controlled studies (RCT) evaluating adults with no history of atrial fibrillation randomised to a pharmacological agent (either beta blocker, calcium channel blocker or digoxin), compared to placebo. Utilising Cochrane guidance, three reviewers screened, extracted and the quality of the evidence was assessed. We used a random effects meta-analysis to compare a rate-control agent with placebo.

Results: Five RCTs (688 subjects, mean age 61±8.9, 69% male) were included. Beta blocker administration prior to elective cardiac surgery significantly reduced the incidence of POAF (OR 0.43, 95%Cl [0.30-0.61], I²=0%) without significant impact on ischaemic stroke (OR 0.49, 95%Cl [0.10-2.44], I²=0%), non-fatal myocardial infarction (OR 0.76, 95%Cl [0.08-7.44], I²=0%), overall mortality (OR 0.83, 95%Cl [0.19-3.66], I²=0%), or length of stay (mean -0.96days 95%Cl [-1.49 to -0.42], I²=0%). An increased rate of bradycardic episodes was observed (OR 3.53, 95%Cl [1.22-10.23], I²=0%).

Conclusions: This review suggests that selective administration of prophylactic oral beta blockers prior to elective cardiac surgery is safe and may reduce the incidence of POAF.