New Atrial Fibrillation Guidelines Offer Patient-centric Recommendations on Use of Newer Anticoagulant Agents

April 3, 2014
Andrew Smith

Changes to the recommended use of various medications and catheter ablations rank among the highlights of comprehensive new guidelines for the treatment of patients with atrial fibrillation.

Changes to the recommended use of various medications and catheter ablations rank among the highlights of comprehensive new guidelines for the treatment of patients with atrial fibrillation (AF).

The document — which was recently released by the American Heart Association (AHA), the American College of Cardiology (ACC) and the Heart Rhythm Society (HRS) — advocates a substantial role for oral anticoagulents that have been introduced and tested since 2006, when the last guidelines were released.

The older drug warfarin (Coumadin) is still recommended as a first-line therapy in many cases and for patients who have mechanical heart valves.

However, the newer medications dabigatran (Pradaxa), rivaroxaban (Xarelto), and apixaban (Eliquis) are advised for patients with nonvalvular AF who are unable to maintain a therapeutic INR level with warfarin.

The three newer drugs have not been tested head-to-head, so the new guidelines make no distinctions among them, but do offer a detailed look at the benefits and risks associated with each. All are recommended equally in the same situations.

"Because what we say in the guideline can affect how a drug is used, we were careful to be even-handed and evidence-based in presenting new drugs," said writing committee chairman Craig T. January, MD, PhD. "Our goal was to provide useful, non-biased information."

As for aspirin, which was recommended in previous guidelines for AF patients with a low risk of stroke, analysis of recent studies led the new guidelines to advocate a much-diminished role for the old standby.

“Data showing that aspirin decreases stroke risk is weak," said January, a professor of Medicine in the Division of Cardiovascular Medicine at the University of Wisconsin-Madison, a fellow of the ACC, and a member of the AHA and HRS.

Recent studies of catheter ablations have led to an expanded role in the new guidelines. The technique is now strongly encouraged to control heart rhythm in some patients who have failed to respond to at least 1 antiarrhythmic drug.

“The efficacy of radiofrequency catheter ablation for maintaining sinus rhythm is superior to current antiarrhythmic drug therapy for maintenance of sinus rhythm in selected patient populations,” the document reads.

“The evidence supporting the efficacy of catheter ablation is strongest for paroxysmal atrial fibrillation in younger patients with little to no structural heart disease and in procedures performed in highly experienced centers.”

In addition to altering treatment recommendations, the new guidelines have altered recommendations about evaluating the dangers patients face. The document advises doctors and patients to abandon (or augment) simple risk calculators for the CHA2DS2-VASc calculator, a tool that provides more information about thromboembolic hazards.

In all, the new documents runs more than 50 pages, organized into sections by topic. Recommendations from prior guidelines were updated or eliminated as new evidence demanded, while some entirely new recommendations were inserted.

Each recommendation is assigned a level of evidence, which estimates of certainty of treatment effect, the size of the treatment effect and the risk-benefit comparison.

“The goal is to have a document that is useful to the practicing physician and makes sense,” January said. “The writing committee worked diligently to ensure that the data, tables, and figures were clear and easy to use.”