Exercise-induced second-degree atrioventricular block in endurance athletes.
Training induces volume- and time-dependent morphological and functional changes in the heart. Heart rhythm disorders, such as atrial arrhythmia (including atrial fibrillation and atrial flutter), are a well-established consequence of such long-term endurance practice. Although resting bradycardia and first-degree atrioventricular persist in veteran athletes, a higher conduction system impairment has never been reported neither at rest nor during exercise. We report here two cases of Type II second-degree atrioventricular block occurring during exercise in middle-age well-trained athletes. Because animal and human studies suggest that a progressive myocardial fibrosis could explain such phenomenon, long-term training could also have consequences on the conduction pathways.
Service de Physiologie et d'Explorations Fonctionnelles, CHU de Strasbourg, Strasbourg, France. stephane.doutreleau@chru-strasbourg.fr
Stéphane
S
Doutreleau
Cristina
C
Pistea
Evelyne
E
Lonsdorfer
Anne
A
Charloux
D054537:Atrioventricular Block / Q000209:etiology* / Q000503:physiopathology*; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D015444:Exercise / Q000502:physiology*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D012420:Running / Q000502:physiology*