Prevalence and clinical significance of QRS fragmentation and low QRS voltages in elite female football players

AIMS: QRS fragmentation (fQRS) and low QRS voltage are electrocardiogram (ECG) findings associated with cardiomyopathy and adverse cardiac events. However, their prevalence and significance in elite female athletes are unknown. The aim of this study was to determine the prevalence and clinical significance of fQRS and low QRS voltage in elite female footballers undergoing cardiovascular screening. METHODS AND RESULTS: Between April 2017 and October 2024, a cohort of 2566 consecutive elite female football players underwent cardiovascular screening, including a 12-lead ECG and echocardiogram. ECGs were analysed for the presence of fQRS and low QRS voltage. These findings were correlated with demographic and echocardiographic data. The mean follow-up period was 4.4 ± 2.5 years. The mean age was 20.13 ± 5.48 years. fQRS in ≥2 contiguous leads was present in 205 (8.0%) athletes, predominantly in the anterior leads (61.3%). fQRS in lead V1 alone was seen in 370 (14.4%) players. Athletes with fQRS demonstrated significantly larger indexed right ventricular (P < 0.001) and left ventricular (LV) (P & 0.033) diameters compared to those without. Low QRS voltage in the limb leads was exceedingly rare, observed in only two (0.1%) athletes. No athlete was diagnosed with cardiomyopathy. CONCLUSION: In elite female footballers, fQRS is a common ECG finding strongly associated with physiological biventricular remodelling, particularly of the right ventricle. Within the context of this screening programme, fQRS was not associated with detectable cardiac pathology or adverse events, suggesting it may represent a feature of the athlete's heart rather than underlying disease. Conversely, the extreme rarity of low QRS voltage suggests it warrants clinical suspicion if detected. These sex-specific findings provide a new reference for interpreting ECGs in this unique population.