Catheter Ablation May be Better Atrial Fibrillation Treatment than Drugs for Serious and Professional Athletes
Feburary 5, 2010 5:27 AM CT
By: Deborah Brauser
Boston – Catheter ablation may be a better treatment option for serious and professional athletes with atrial fibrillation (AF) than antiarrhythmic drugs (AADs), according to a presentation at the 15th Annual Boston Atrial Fibrillation Symposium by Dr. Riccardo Cappato (Institute Policlinics San Donato, Milan, Italy).
“About 5% of all athletes complain of prolonged palpitations at some time in their sporting life,” said Dr. Cappato. “In about 60% of the cases, lone AF or atrial flutter is the dominant documented arrhythmia at the time.”
He reported that in one recent study, 63% of athletes (mean age, 44 years) who participated in sports more than 3 hours per week experienced at least 1 episode of atrial fibrillation compared to 15% of age matched controls who did not participate as much. Plus, the prevalence increased as the total number of hours per week or years of activity increased.
“AF occasionally affects athletes by impairing their ability to compete and leading to non-eligibility at pre-qualification, markedly impacting their quality of life,” said Dr. Cappato. In fact, he reported that in Italy, a certificate showing a healthy pre-participation screening is required to compete.
“This link between AF and sports participation is poorly understood but may possibly be due to an increase in intra-atrial wall pressure from dynamic endurance sports such as cycling and rowing, autonomic changes, or inflammatory and immunologic changes facilitated by overtraining or even illicit drug intake.”
Antiarrhythmic drug therapy has not been popular with this patient population. “Treatment with AADs in the general population has proven dismally ineffective, with no more than a 50% success rate except for amiodarone,” said Dr. Cappato. “Even when effective, AADs significantly affect an athlete’s physical performance and inhibit eligibility at pre-qualification screenings.”
For these reasons, he recently conducted a small study of catheter ablation by pulmonary vein isolation as treatment for 38 athletes (mean age, 41.2 years) with disabling palpitations on the basis of lone atrial fibrillation, all of whom had been disqualified at a competition’s prequalification screening. After undergoing catheter ablation, all athletes had a stable restoration of their sinus rhythm.
In a much larger study, 271 competitive athletes (made up mostly of soccer players, cyclists, and swimmers, but also including climbers, basketball players, and volleyball players) with atrial fibrillation from a number of high volume centers underwent catheter ablation. Of these, 184 patients with paroxysmal and 54 with persistent atrial fibrillation achieved success without AADs.
“Catheter ablation offers an unprecedented opportunity for these athletes to come back to their sport, especially when healthy [pre-participation screening] certificates are required to compete in countries such as mine.”
During the Q&A session after his presentation, Dr. Cappato stressed that regular athletes with AF and those with AF that make their money from athletics are 2 very different groups. “This isn’t a group where you can just suggest less exercise, as we can with highly conditioned non-athletes. They want to go back to their activity. That’s why we need to listen and do what’s best for each patient—no blanket treatments as though one group is exactly the same as another.”
Session moderator Dr. Eric Prystowsky (St. Vincent Hospital, Indianapolis, IN) agreed, commenting that medications are such a problem for serious athletes that his center often jumps straight to catheter ablation as first line therapy for them.
During the same session, Dr. Stanley Nattel (Montreal Heart Institute, Montreal, Canada) presented a small animal study that evaluated rats running 1 hour a day, 5 days a week over a 16-week period. Although the results will need to be replicated in large human studies, the findings did suggest that the strenuous exercise may have contributed to the rats’ development of atrial fibrillation.
“The mechanisms occurring after chronic high-level exercise included ventricular diastolic dysfunction, followed by atrial overload, then atrial enlargement, atrial fibrosis, and then AF. In parallel, there was also an increased vagal tone,” explained Dr. Nattel. “In other words, chronic exercise training provides a substrate for AF.”
However, his team found that treatment with atropine could reverse the effects of AF and prevent its re-induction. “We also think that the collagen increase is reversible too,” added Dr. Nattel.
When asked by an audience member what kinds of exercise he thinks tends to contribute to atrial fibrillation, Dr. Nattel answered: “I’d say that would be the more cardiovascular with sustained training types, such as soccer, cross country skiing, and running — which all convey a vagal tone component.”
Finally, he mentioned that he has seen cases where atrial fibrillation has gone away completely after his human patients have stopped their high level conditioning.
From Boston Atrial Fibrillation Symposium Sessions:
- Atrial Fibrillation in Competitive Athletes— Prevalence, Pathophysiology, and Management
- Basic Mechanisms by Which Exercise Training Promotes AF
Deborah Brauser is a freelance medical reporter and a member of the Association of Health Care Journalists.