Abstract

Although the possible occurrence of supraventricular tachyarrhythmias in asymptomatic athletes with ventricular preexcitation (VP) is a well known fact, few studies are available about electrophysiological characteristics of these subjects. In this report, 10 asymptomatic athletes with VP are presented (4 played football, 3 basketball, 1 swimming ball, 1 fencing and 1 windsurf) in which an endocavitary electrophysiologic study (EPS) was performed. EPS had three end points: (1) to induce reciprocating tachycardia, (2) to study retrograde ventriculo-atrial conduction, (3) to provoke atrial fibrillation (af) or flutter (AF). Conclusion: (1) as well known, a picture of VP can be due, even if rarely, to Mahaim and not to Kent fibers; (2) the absence of arrhythmias in WPW asymptomatic athletes is related to retrograde electrophysiological properties of Kent bundles which can be free from retrograde conduction or have a long retrograde refractory period; (3) af/AF can be induced in most cases by a moderately aggressive stimulation, but in 40 cases high frequency atrial bursts are required; (4) af/AF in half of the cases resolves spontaneously in few seconds and in the majority of cases is conducted to the ventricles with low rates. Only in 20 af/AF persists several minutes and determines a high ventricular response. The prognostic judgment in these cases should also take into account the aggressivity required to provoke af/AF. Verf.-Referat