Frequency of fragmented QRS in sports activity: a pilot study

BACKGROUND: Fragmented QRS (fQRS), is a marker of intraventricular conduction delay. No sufficient data are available regarding the presence in different sports disciplines. The present study aims to evaluate the frequency of fQRS in athletes and the morphological myocardial associated pattern. METHODS: This retrospective study of 5 years, involved 605 subjects and evaluated for the eligibility in competitive sport activity. A sample of 100 subjects for 6 kinds of sport was considered. Fragmented QRS was defined as the presence, during a resting ECG, of various RSR' patterns in at least two contiguous leads. All subjects had an echocardiographic examination. RESULTS: fQRS was found in 47 athletes of the 605 subjects. fQRS+ subjects were older than fQRS- (33.17 vs. 24.12 P<0.001) and were predominantly male (89.4% vs. 10,6% P=0.007). The presence of fQRS had a different prevalence among sports. Fragmented QRS was independently associated with age (OR=1.026, 95% CI 1.006-1.047; P=0.010), sex (OR=0.354, 95% CI 0.133-0.943; P=0.038), left ventricle cardiac mass index values (OR=1.017, 95% CI 1.001-1.033; P=0.033) and E peak (OR=0.979, 0.959-0.999; P=0.043) in multivariate analysis. CONCLUSIONS: The prevalence of fQRS in sport disciplines appears to be around 13% to 2% with major evidence among older male subjects. Despite the presence of physiological hypertrophy in athletes, no significant influence was found regarding the type of sport practiced on the prevalence of fQRS. A larger investigation will be necessary to validate this first hypothesis.