Effects of Training on the Electrophysiologic Properties of Atrium and Accessory Pathway in Athletes with Wolff-Parkinson-White Syndrome

Abstract

Twenty-two subjects with Wolff-Parkinson-White (WPW) electrocardiographic pattern performing agonistic physical activity were referred to our laboratory to assess arrhythmogenic risk (group 1). This allowed us to evaluate a less known aspect, namely that of effects of training on the electrophysiologic properties of the atrium and accessory pathway. This was done utilizing a control group of 10 WPW patients who did not perform agonistic physical activity (group 2). All subejcts were symptom free, and without signs of associated cardiopathy if we exclude 1 patient of group 1 who presented moderate mitral valve prolapse. Group 1 patients showed significantly higher mean values for basic cycle length (p < 0.001), atrial effective (p < 0.04) and functional (p < 0.02) refractory period, and anterograde effective refractory period of the accessory pathway (p < 0.02). The different behavior observed in group 1 patients could be explained considering the known influence of training on the equilibrium of the autonomic nervous system. Moreover, it is noteworthy that the two groups did not differ for inducibility of atrial fibrillation (AF). This should be taken into account considering the importance of AF in WPW. In conclusion, our study does not demonstrate any negative electrophysiologic effects of training in patients with WPW.

Effects of chronic exercise on myocardial refractoriness: a study on isolated rabbit heart

“…Indeed some authors did not find any modification on atrial refractory periods in humans (Brorson et al. 1976), whereas others reported an increase in atrial refractoriness by training (Mezzani et al. 1990).…”

The training-induced changes on automatism, conduction and myocardial refractoriness are not mediated by parasympathetic postganglionic neurons activity

“…With respect to atrial refractoriness and its modification by physical training, it has been reported either no change (7) or an increase (24) in athletes with Wolff-Parkinson-White syndrome. Experimental studies carried out in isolated rabbit heart have shown that although the differences were not statistically significant, AERP tended to increase (p = 0.09) in the hearts of trained animals (39).…”

Management of Young Athletes with Asymptomatic Preexcitation—A Review of the Literature

“…It has been proven that competitive athletes especially in endurance sports are at higher risk of developing atrial fibrillation, even after discontinuation of athletic activity [ 4 , 5 ]. On the other hand intensive training does not seem to affect the properties of the pathway itself [ 35 ].…”