New Atrial Fibrillation Guidelines Emphasize Stroke Prevention

NEW YORK, August 2 -- Stroke risk trumps age, gender or other history of heart disease in determine which atrial fibrillation patients will benefit from anticoagulation, according to revised guidelines issued today by three major heart societies.

Stroke is a natural focus of the new guidelines, said Valentin Fuster, M.D., Ph.D., director of the Mount Sinai Cardiovascular Institute here, because atrial fibrillation is a major risk factor for stroke, and strokes associated with atrial fibrillation "are especially large and disabling."

Dr. Fuster co-chaired the writing committee for the revised guidelines, which were published online by the American College of Cardiology, the American Heart Association, and the European Society of Cardiology. They appeared in Circulation, Journal of the American Heart Association, the Journal of the American College of Cardiology and the European Heart Journal.

The changes were the first revision to the atrial fibrillation guidelines since 2001, and they reflect the recently published evidence from a number of large clinical trials.

The anticoagulation recommendations ranged from daily aspirin therapy for patients with no stroke risk factors (81 mg to 325 mg), to aspirin or Coumadin (warfarin) for those at moderate risk of stroke and Coumadin for high risk individuals. These were defined as atrial fibrillation patients with a history of stroke, transient ischemic attack, systemic embolism, or a prosthetic heart valve. Coumadin was also recommended for those with two or more moderate risk factors (over age 75, hypertension, congestive heart failure, impaired left ventricular function or diabetes).

In addition to recommending long-term anticoagulation for all atrial fibrillation patients with risk factors for thromboembolism, the updated guidelines suggested that atrial fibrillation may be managed as a chronic condition as long as attention is paid to antithrombotic therapy and control of ventricular rate.

Although it is "reasonable to make at least one attempt to restore sinus rhythm, the AFFIRM study showed no difference in survival or quality of life with rate control compared to rhythm control strategies," the guidelines authors wrote.

For that reason attempts to restore sinus rhythm should be weighed against the "severity of arrhythmia-related symptoms and the potential risk of antiarrhythmic drugs," they wrote. And in any case, "anticoagulation and rate control are important before cardioversion."

The guidelines also addressed catheter ablation for the first time and Dr. Fuster said that patients with recurrent atrial fibrillation who do not respond to drug therapy may benefit from this relatively new procedure as long as there is "little or no left atrial enlargement."