More than 2 million Americans have atrial fibrillation, and there are about 160,000 new cases each year. The number is increasing, due in part to the aging population and the obesity epidemic.
Drugs such as beta blockers and calcium channel blockers can slow the heart rate during an A-Fib episode. Other drugs such as flecainide and propafenone can help maintain a normal rhythm. When drugs don't work or produce unacceptable side effects, alternative treatments include a pacemaker, surgery and catheter ablation.
In the ablation procedure, an electrophysiologist destroys small areas of heart tissue that are responsible for the erratic electrical signals. A catheter (thin flexible tube) is guided through blood vessels to the heart. The tip of the catheter delivers radiofrequency energy that heats and destroys tissue. Possible adverse effects include irritation of the lining of the heart, fluid in the lungs or around the heart, bleeding, clots and stroke.
In the study, 106 patients with frequent episodes of atrial fibrillation were randomly assigned to undergo ablation and 61 similar patients were randomly assigned to receive drug therapy. All patients had experienced at least three episodes of atrial fibrillation during the previous six months and had failed at least one attempt to control the rhythm with drugs.
The study was funded by Biosense Webster, which makes the ThermoCool catheter used in the trial. Wilber is a consultant to the company.
The study was the largest to date to compare ablation to drug therapy for atrial fibrillation. Earlier studies involved single centers and smaller sample sizes, Wilber said. An additional study called CABANA is designed to determine whether ablation patients live longer than patients receiving medication. Researchers will follow about 3,000 patients for three years.
|Contact: Jim Ritter|
Loyola University Health System