Atrial fibrillation – stick with rate control

In today’s NEJM -

Rhythm Control versus Rate Control for Atrial Fibrillation and Heart Failure

Background It is common practice to restore and maintain sinus rhythm in patients with atrial fibrillation and heart failure. This approach is based in part on data indicating that atrial fibrillation is a predictor of death in patients with heart failure and suggesting that the suppression of atrial fibrillation may favorably affect the outcome. However, the benefits and risks of this approach have not been adequately studied.

Methods We conducted a multicenter, randomized trial comparing the maintenance of sinus rhythm (rhythm control) with control of the ventricular rate (rate control) in patients with a left ventricular ejection fraction of 35% or less, symptoms of congestive heart failure, and a history of atrial fibrillation. The primary outcome was the time to death from cardiovascular causes.

Results A total of 1376 patients were enrolled (682 in the rhythm-control group and 694 in the rate-control group) and were followed for a mean of 37 months. Of these patients, 182 (27%) in the rhythm-control group died from cardiovascular causes, as compared with 175 (25%) in the rate-control group (hazard ratio in the rhythm-control group, 1.06; 95% confidence interval, 0.86 to 1.30; P=0.59 by the log-rank test). Secondary outcomes were similar in the two groups, including death from any cause (32% in the rhythm-control group and 33% in the rate-control group), stroke (3% and 4%, respectively), worsening heart failure (28% and 31%), and the composite of death from cardiovascular causes, stroke, or worsening heart failure (43% and 46%). There were also no significant differences favoring either strategy in any predefined subgroup.

Conclusions In patients with atrial fibrillation and congestive heart failure, a routine strategy of rhythm control does not reduce the rate of death from cardiovascular causes, as compared with a rate-control strategy.

Over the past decade, the thought of converting atrial fibrillation to sinus rhythm to improve outcomes no longer has currency.  For years we worked hard to convert from atrial fibrillation and maintain sinus rhythm.  We used a variety of anti-arrythmics, many of which proved to actually be proarrhythmic. 

Today we teach rate control and anticoagulation as first line therapy.  We only revert to cardioversion when the patient has symptoms which cardioversion resolves.

This represents a major paradigm shift.  The current article should end the controversy.  CHF patients remained the one patient population that cardiologists "knew" would benefit from sinus rhythm.  Afterall, our teachers explained that the atrial kick provides around 15% of the eventual stroke voluem  But this study shows that the atrial kick does not really matter to patients.

As an internist, I have taught about atrial fibrillation for 30 years.  My teaching has changed dramatically over the years.  This study adds to the discussion.  I am surprised that neither MedPage nor Medscape have discussions of this article.  I guess rate control for atrial fibrillation has become so standard that this article does not shock anyone.

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Addendum

Medpage added a discussion – Rate Control Preferred Therapy for Atrial Fibrillation Plus Heart Failure