Impact of physical deconditioning on ventricular tachyarrhythmias in trained athletes

ObjectivesThe purpose of this research was to evaluate the impact of athletic training and, in particular, physical deconditioning, on frequent and/or complex ventricular tachyarrhythmias assessed by 24-h ambulatory (Holter) electrocardiogram (ECG).BackgroundSudden deaths in athletes are usually mediated by ventricular tachyarrhythmias.MethodsTwenty-four hour ambulatory ECGs were recorded at peak training and after a deconditioning period of 19 ± 6 weeks (range, 12 to 24 weeks) in a population of 70 trained athletes selected on the basis of frequent and/or complex ventricular tachyarrhythmias (i.e., ≥2,000 premature ventricular depolarization [PVD] and/or ≥1 burst of non-sustained ventricular tachycardia [NSVT]/24 h).ResultsA significant decrease in the frequency and complexity of ventricular arrhythmias was evident after deconditioning: PVDs/24 h: 10,611 ± 10,078 to 2,165 ± 4,877 (80% reduction; p < 0.001) and NSVT/24 h: 6 ± 22 to 0.5 ± 2, (90% reduction; p = 0.04). In 50 of the 70 athletes (71%), ventricular arrhythmias decreased substantially after detraining (to