LEUVEN, BELGIUM. There is sufficient evidence that endurance athletes are far more likely to develop lone atrial fibrillation (LAF) than are more sedentary people. See Endurance Exercise: Is It Worth It?
. However, it is not clear whether a LAF condition associated with endurance sports responds differently to catheter ablation for the purpose of curing atrial fibrillation (AF). Researchers at the University of Leuven now provide an answer to this question.
Their study included 94 athletes and a matched control group of non-athletes (sedentary persons) with AF (90% paroxysmal and 10% persistent). Mean age was 51 years, and AF symptoms had been present for a median of 4 years prior to the initial ablation. The athlete group was divided into two groups – group 1 consisted of 59 endurance athletes with an average lifetime (since age of 14) number of sports practice hours of 10,550, while group 2 consisted of 35 non-endurance athletes with an average lifetime sports practice hours of 3,450. The average lifetime sports practice hours in the control group was 450. Endurance training involved running, cycling, swimming or rowing.
All study participants underwent a pulmonary vein isolation (PVI) procedure using electrophysiologic (Lasso catheter and fluoroscopic guidance) mapping using an irrigated-tip catheter. Roof lines were applied as required and 80% of patients also underwent a right atrial flutter (cavo-tricuspid isthmus) ablation. Patients were followed up with ECGs and Holter monitoring at 6 weeks, 6 months and 1 year, and yearly thereafter. Recurrences during the first 6 weeks post-ablation were not counted.
Three years after the initial ablation, 52% of controls, 54% of endurance athletes, and 66% of non-endurance athletes had experienced one or more AF recurrences. Twenty-seven (20%) of ablatees underwent follow-up procedures. Three years after the final procedure, 63% of the control group were in normal sinus rhythm (NSR) without the use of antiarrhythmic drugs, while 24% managed to remain afib-free with the aid of previously ineffective antiarrhythmics (Class II or II). Corresponding numbers for endurance and non-endurance athletes were 54% and 30%, and 40% and 45% respectively. Overall success rates (no AF with or without the aid of antiarrhythmics) were thus 87% for the control group, 84% for endurance athletes, and 85% for non-endurance athletes. The Belgian researchers conclude that having been a lifelong endurance athlete does not decrease the chance of achieving freedom from AF following one or more PVI procedures. Koopman, P, Heidbuchel, H, et al. Efficacy of radiofrequency catheter ablation in athletes with atrial fibrillation. Europace, Vol. 13, 2011, pp. 1386-93 Editor's comment
: For most afibbers a successful PVI procedure is one that results in complete freedom from AF and other tachycardia episodes without the use of antiarrhythmic drugs. Using these criteria as indicators of complete success, actual 3-year success rates after final ablation become:
- Control group - 63%
- Endurance athletes - 54%
- Non-endurance athletes - 40%
The differences in the above percentages are not statistically significant.