SNOWMASS, COLO. — The large multicenter CABANA trial, now recruiting, may be the last and best chance to learn if maintaining sinus rhythm confers a survival advantage over rate control in patients with atrial fibrillation.
CABANA (Catheter Ablation Versus Antiarrhythmic Drug Therapy for Atrial Fibrillation) is randomizing roughly 3,000 patients with all types of symptomatic atrial fibrillation—paroxysmal, persistent, and long-standing persistent—to left atrial catheter ablation, antiarrhythmic drug therapy, or rate control medication. The primary end point will be total mortality with at least 2 years of follow-up.
Patients with atrial fibrillation (AF) should be encouraged to enroll in this trial; it's a chance to receive catheter ablation as first-line therapy, should they be randomized to that study arm. In contrast, current clinical practice is generally to reserve ablation therapy for patients who have failed at least one antiarrhythmic drug, Dr. Roger A. Winkle noted at a conference sponsored by the American College of Cardiology.
Catheter ablation as definitive treatment for AF has evolved over a relatively short time from an experimental procedure to an important therapeutic option that provides cure or significant palliation in the majority of patients, with acceptable complication rates at high-volume centers with experienced providers.
The results are “vastly superior” to antiarrhythmic drug therapy in terms of maintenance of sinus rhythm, improvement in quality of life, and reduction of symptoms. That's why CABANA employs ablation as state-of-the-art rhythm control therapy in a showdown against rate control and antiarrhythmic drugs, explained Dr. Winkle, director of electrophysiology at Sequoia Hospital, Redwood City, Calif.
Maintaining sinus rhythm should reduce stroke risk, avoid the side effects of long-term anticoagulation, and improve survival. However, “all of the studies of rate versus rhythm control with the medications we currently have available have been neutral. It's possible that we can't show a beneficial effect of sinus rhythm because we really don't have agents that keep most people in sinus rhythm. Or alternatively, the current antiarrhythmic drugs and warfarin therapy that we use may cause enough harm to offset the benefits of being in sinus rhythm. We just don't have the answer to that,” the cardiologist said.
Secondary end points in the CABANA trial include AF recurrence, stroke, quality of life, and cost effectiveness. The principal investigator is Dr. Douglas L. Packer of the Mayo Clinic, Rochester, Minn. Participating sites are well distributed geographically across the United States (www.cabanatrial.org
Disclosures: The trial is funded by St. Jude Medical, Biosense Webster, and the National Heart, Lung, and Blood Institute. Dr. Winkle reported having no relevant financial interests.