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.