Clinical question: What is the best management strategy for postoperative atrial fibrillation?
Bottom line: For new-onset atrial fibrillation (AF) following cardiac surgery, both rate control and rhythm control are reasonable strategies. There is no a clear advantage of one over the other. (LOE = 1b)
Reference: Gillinov AM, Bagiella E, Moskowitz AJ, et al. Rate control versus rhythm control for atrial fibrillation after cardiac surgery. N Engl J Med 2016;374(20):1911–1921.
Study design: Randomized controlled trial (nonblinded)
Funding source: Government
Setting: Inpatient (any location) with outpatient follow-up
Postoperative AF is a common complication of cardiac surgery. In this trial, investigators identified more than 2000 patients who were undergoing coronary-artery bypass grafting and/or cardiac valve surgery. Of these patients, one-third developed new-onset AF and were randomized to receive either rate control or rhythm control.
In the rate-control group, patients received medications to slow heart rate to less than 100 beats per minute. If sinus rhythm was not achieved, these patients could then receive rhythm control per their physician's discretion. In the rhythm-control group, patients received amiodarone with or without rate-lowering medication, followed by cardioversion if AF persisted for 24 to 48 hours. The crossover rate in both groups was approximately 25% due to either drug ineffectiveness in the rate-control group or drug side effects in the rhythm-control group. All patients who remained in AF after 48 hours received anticoagulation.
The 2 groups were similar at baseline: mean age was 69 years, 75% were male, and 94% were white. Intention-to-treat analysis was used to test the primary endpoint of number of days in the emergency department or hospital within 60 days after randomization. There was no significant difference detected in this outcome between the 2 groups, even when the initial length of stay was adjusted for discharge readiness from an AF perspective. A sensitivity analysis accounting for the large number of crossovers also confirmed this finding. More than 90% of patients in both groups had a stable heart rhythm at the 60-day follow-up. Complication rates and 30-day readmission rates were also similar in the 2 groups.
Dr. Kulkarni is an assistant professor of hospital medicine at Northwestern University in Chicago.