Low QRS voltages in Olympic athletes: Prevalence and clinical correlates

Background Recently, novel interest in low QRS voltages was prompted by the observation that low QRS voltages are present in arrhythmogenic cardiomyopathy patients, even before occurrence of symptoms/events. Aim The purpose of this study was to assess prevalence and clinical correlates of low QRS voltages in Olympic athletes, evaluated and followed-up within our cardiovascular screening programme. Methods Five hundred and sixteen athletes consecutively examined (2010–2011) were included in this study. A low QRS voltage was defined as amplitude of QRS <0.5 mV in limb and/or <1.0 mV in precordial leads. Cardiovascular evaluation included 12-lead and exercise electrocardiogram, echocardiography and, selectively, additional tests to confirm diagnosis. Athletes were followed-up for 5 ± 2 (1–9) years. Results The majority of athletes (493; 96%) showed normal/increased R/S-wave voltages, but 23 (4%) had low QRS voltages. No differences were observed in low QRS voltage athletes compared to normal/increased QRS voltages for QRS duration, QTc and PR intervals, left ventricular cavity size and mass, or gender and sport participated. However, premature ventricular beats, occurred more frequently in low QRS voltages (39% vs 7%; p < 0.001), with patterns suggesting origin from left or right free wall. No diseases or events were registered in low QRS voltage athletes over the follow-up. Conclusions In Olympic athletes, the prevalence of low QRS voltages was 4%. Athletes with low QRS voltages did not differ from other athletes according to sport participated in or cardiac dimensions. However, more frequently (39% vs 7%) they showed premature ventricular beats, originating from either the left or right free ventricular wall. Therefore, long-term follow-up with serial clinical evaluations is needed in low QRS voltage athletes, in order to definitely clarify the clinical significance.