Athlete’s Heart or Heart at Risk? Cardiac Remodeling and Exercise-Induced Ventricular Arrhythmias in Elite Athletes

BACKGROUND: Ventricular ectopic beats (VEBs) are frequently observed in athletes, but their clinical significance remains debated. We aimed to assess the prevalence, pattern of exercise-induced VEBs, and their association with exercise-induced cardiac remodeling (EICR) in elite athletes. METHODS: We analyzed a large cohort of Olympic athletes who underwent comprehensive preparticipation screening, including exercise-electrocardiography test and echocardiography. VEB morphology was classified as common (left bundle branch block, with inferior axis, and fascicular) or uncommon, including polymorphic. RESULTS: We enrolled 2525 athletes (mean age, 25.7±5.2 years; 45.1% women); 14.8% of athletes had exercise-induced VEBs, more frequently men (16.7% versus 12.4%; P =0.002), with no differences between sport disciplines ( P =0.295). The VEB pattern was defined in 283 (ie, 76%), including 135 (48%) common and 148 (52%) uncommon, including polymorphic. Prevalence of common VEBs increased proportionally with the functional capacity (as W/kg), ranging from 16.3.% in I quartile to 40% in IV quartile ( P <0.0001), while no differences existed in those with uncommon VEBs ( P =0.140). Moreover, athletes with common VEBs showed a greater EICR, including a larger right ventricle (with wider right ventricular outflow tract; P =0.014; right ventricular end-diastolic area; P =0.016) and left ventricle (greater left ventricular mass indexed; P =0.037; a higher prevalence of eccentric remodeling; P =0.019). On the contrary, no relationship with cardiac remodeling or exercise capacity was seen in athletes with uncommon VEBs and in those without VEBs. CONCLUSIONS: Exercise-induced common VEBs in athletes seem to be associated with EICR and superior exercise performance and may represent a benign phenomenon, expression of the pathophysiologic consequences of EICR. Instead, uncommon VEBs were not related to the extent of EICR or the level of exercise performance, suggesting a nonphysiological nature.