Strictly controlling the heart rate of patients with atrial fibrillation (AF) provides no advantage over more lenient heart rate control, experts reported in a focused update of the 2006 guidelines for the management of patients with AF, that also lists several other changes. The new recommendations were published online Dec. 20 in Circulation, the Journal of the American College of Cardiology, and HeartRhythm Journal.
The heart rate recommendation states that strict treatment to control a patient's heart rate (at less than 80 beats per minute (bpm) 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 bpm in patients with persistent, or continuous, AF with stable functioning of the ventricles.
"The evidence showed rigid control did not seem to benefit patients," said L. Samuel Wann, MD, chair of the focused update writing group and director of cardiology at the Wisconsin Heart Hospital in Milwaukee. "We don't need to be as compulsive about absolute numbers, particularly doing exercise tests and giving multiple drugs based solely on heart rate. Patients with symptoms due to rapid heart action need treatment, and the long-term adverse effects of persistent tachycardia on ventricular function are still of concern."
The evidence-based updates, which reflect major advances in disease management, include:
A combination of aspirin and the oral antiplatelet drug clopidogrel (Plavix, Bristol-Myers Squibb/Sanofi-Aventis) "might be considered" to prevent stroke or other types of blood clots in AF patients who are poor candidates for warfarin. Although warfarin remains effective, it requires patients to have regular testing to monitor its effectiveness and dosage adjustment. "It's a minor inconvenience for most, but a major inconvenience for some," Wann said.
New research showed dronedarone (Multaq, Sanofi-Aventis), which is administered as a pill, could reduce hospitalizations for cardiovascular events related to AF. 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 four weeks, especially if they have depressed ventricular function. Dronedarone is associated with less hospitalizations and less side effects than amiodarone (Cordarone, Wyeth/Pfizer).
Several new or revised recommendations support the role of catheter ablation as a treatment to maintain normal heart rhythm. Ablation is useful when performed for selected patients at experienced centers (in which more than 50 cases are performed annually). For those patients with symptomatic paroxysmal AF, who have not had success with drug treatment, do not have severe lung disease and have a normal or mildly dilated left atrium and normal or mildly reduced function of the left ventricle, catheter ablation "is useful in maintaining sinus rhythm."
The treatment option is also reasonable for patients with symptomatic persistent AF, and it may be reasonable to treat symptomatic paroxysmal AF in patients with significant enlargement of the left atrium or with significant left ventricle dysfunction.
These 2010 focused updates change the 2006 Guidelines for the Management of Patients With Atrial Fibrillation that were developed by the American College of Cardiology, American Heart Association and European Society of Cardiology.