Hospital Stay, Complications Similar for Rate vs Rhythm Control in Post-Op Atrial Fibrillation

The length of hospital stay and complications was similar for rate control compared to rhythm control in a cohort of patients with postoperative atrial fibrillation (AF).

A. Marc Gillinov, MD of the Department of Thoracic and Cardiovascular Surgery at Cleveland Clinic Foundation in Cleveland, Ohio, presented the study findings at the 2016 American College of Cardiology Annual Scientific Sessions & Expo (ACC) in Chicago.

“There is no clear advantage of 1 treatment strategy over the other in terms of hospital days or complications,” noted Dr Gillinov at an ACC press conference.

Postoperative AF continues to be the most common complication after cardiac surgery despite prevention efforts made by previous research. There are currently 2 methods to manage post-cardiac surgery AF: rate control and rhythm control

Dr Gillinov and colleagues randomly assigned 2109 patients to receive rhythm control or rate control to assess the difference in the length of hospital stay within 60 days after randomization. All patients in the study received elective cardiac surgery for heart valve or coronary artery disease and experienced new-onset postoperative AF.

The rate control group was treated with a goal of reaching a resting heart rate of <100 beats per minute, with the option to switch to rhythm control if needed. In contrast, the rhythm control group received amiodarone with the possibility of adding a rate controlling agent. Direct current cardioversion was recommended for persistent AF after 24 to 48 hours. Likewise, participants with persistent AF after 48 hours were recommended for anticoagulation. 

Postoperative AF developed in 33% (n=695) of patients with 523 patients undergoing randomization. AF developed in 33.7% of those who underwent valve surgery, 28.1% who underwent coronary-artery bypass grafting, and 47.3% who received both.

Within the groups, 24% of the rhythm control group required beta-blockers or calcium channel blockers and 26.7% of the rate control group required cardioversion or amiodarone for protocol-related clinical reasons.

More patients in the rhythm control changed therapy after discharge compared to before discharge for the rate control group. Likewise, treatment change was secondary to side effects of the rhythm drug in 65% (n=40).

There were no significant differences between the rate control and rhythm control groups in the number of hospital days 60 days after randomization (6.4 vs 7.0 days; P=.76)

Further, there were no significant differences for adverse events (P=.61) or death (P=.64) between the groups.

Indications for anticoagulation were met in 31.8% of patients in the rhythm control group compared to 46.2% of the rate control group.

At the conclusion of the study, there was no AF demonstrated within the previous 30 days in 97.9% and 93.8% of patients in the rhythm control and rate control groups, respectively (P=.02). Later, at the 60-day follow-up, there was no evidence of AF in 86.9% of patients in the rhythm control group and 84.2% of the patients in the rate control group at discharge (P=.41). 

“An initial strategy of rate control in a hemodynamically stable patient is probably reasonable because you avoid the toxicity associated with the antiarrhythmic drug amiodarone. And because if you do need to switch from rate control to rhythm control you can usually discern that need while…the patient is still in the hospital,” Dr Gillinov stated.

Disclosures: The study was supported by the National Heart, Lung, and Blood Institute and the National Institute of Neurological Disorders and Stroke. Drs Ailawadi, Gillinov, Gammie, and Kern reported disclosures related to biotechnology and/or pharmaceutical companies.

References

1. Gillinov AM, Bagiella AJ, Moskowitz JM, et al. Presentation 410-12.Rate control vs rhythm control for atrial fibrillation after cardiac surgery. Presented at the 65th Annual Scientific Sessions and Expo of the American College of Cardiology. April 2-4, 2016; Chicago, IL.
2. Gillinov AM, Bagiella AJ, Moskowitz JM, et al. Rate control vs rhythm control for atrial fibrillation after cardiac surgery. N Engl J Med. 2016. doi: 10.1056/NEJMoa1602002.