NEW YORK (Reuters Health) – In patients with atrial fibrillation, strict heart rate control provides no advantage over more lenient control, according to a focused update of the 2006 guidelines for the management of patients with atrial fibrillation.

The heart rate recommendation, one of several in the update, states that strict treatment to keep a patient’s heart rate at less than 80 beats per minute at rest and less than 110 during a six-minute walk is not beneficial over a more lenient approach to achieve a resting heart rate of less than 110 in patients with persistent atrial fibrillation and stable ventricular function.

“The evidenced showed rigid control did not seem to benefit patients,” Dr. L. Samuel Wann, chair of the focused update writing group and director of cardiology at the Wisconsin Heart Hospital in Milwaukee, noted in a written statement.

According to the writing committee, the focused update “reflects a consensus of expert opinion after a thorough review primarily of late-breaking clinical trials identified through a broad-based vetting process as being important to the relevant patient population, as well as other new data deemed to have an impact on patient care.”

The focused update also states that the addition of clopidogrel to aspirin to reduce the risk of major vascular events, including stroke, “might be considered” in atrial fibrillation patients in whom warfarin is considered “unsuitable due to patient preference or the physician’s assessment of the patient’s ability to safely sustain anticoagulation.” Warfarin is a “minor inconvenience for most, but a major inconvenience for some,” Dr. Wann noted.

The update also addresses new research on the antiarrhythmic drug dronedarone (Multaq, Sanofi-Aventis). It states that use of dronedarone is “reasonable to decrease the need for hospitalization for cardiovascular events in patients with paroxysmal atrial fibrillation or after conversion of persistent atrial fibrillation.” The drug can be initiated during outpatient therapy.

The update also states that dronedarone should not be given to patients with NYHA class IV heart failure or patients who have had an episode of decompensated heart failure in the past month, especially if they have left ventricular ejection fraction of 35% or less. Dronedarone generally less efficacious than amiodarone, but is associated with fewer hospitalizations and side effects, the update states.

The update supports the role of catheter ablation as a treatment to maintain normal sinus rhythm. Catheter ablation is useful when performed at experienced centers (in which more than 50 cases are performed annually), in select patients with significantly symptomatic, paroxysmal atrial fibrillation who have failed treatment with an antiarrhythmic drug and have normal or mildly dilated left atria, normal or mildly reduced left ventricular function and no severe pulmonary disease.

“Catheter ablation is one of the most rapidly growing procedural areas in cardiology right now, and the evidence does support that,” Dr. Wann said.

The focused update on the management of atrial fibrillation is published in the December 28, 2010/January 4, 2011 issue of the Journal of the American College of Cardiology, the January 4, 2011 issue of Circulation, and the December 2010 issue of the journal HeartRhythm.