Some abnormal heart rhythms that do not respond to drugs should instead be treated with a procedure that cauterizes the muscle around a vein that carries blood from the lungs to the heart, a new study suggests.
The study, published Wednesday in The Journal of the American Medical Association, was one of the most comprehensive clinical trials of the procedure as it is currently practiced, said the lead author, Dr. David J. Wilber, director of the Cardiovascular Institute at Loyola University Medical Center. It was financed by Biosense Webster, maker of the catheters used in the procedures.
The trial, in 19 hospitals, included 167 patients whose intermittent atrial fibrillation had not responded to medication; 106 were randomly assigned to receive the procedure, called catheter ablation; 61 were given another drug.
After nine months, 66 percent of the patients who underwent catheter ablation were free of fibrillation episodes, compared with only 16 percent of those treated with anti-arrhythmic drugs.
Dr. Wilber compared the procedure to cutting down a swath of trees to prevent a forest fire from spreading. The ablation works by “creating a ring of dead muscle around the pulmonary veins, so you can get rid of the electrical activity there,” he said, adding, “There is a lot of reserve muscle in the heart.”