Low QRS voltage in Paralympic athletes: An unexpectedly high prevalence

Low QRS voltage (LQRSV) is an uncommon electrocardiographic finding in able-bodied athletes and it is investigated to exclude underlying cardiomyopathy. Its prevalence and clinical meaning in Paralympic athletes (PA), particularly those with spinal cord injury (SCI), remain unknown.

To describe the prevalence of LQRSV in elite PA and to explore its associations with cardiac structure and functional parameters, with attention to differences between athletes with and without SCI.

193 healthy Olympic PA underwent anthropometric assessment, 12‑lead-ECG, comprehensive echocardiography, and cardiopulmonary exercise testing. Athletes were classified according to disability (SCI vs. non-SCI). LQRSV was defined according to international criteria.

PA had mean age 32.7 ± 9.7 years, and 44% were females. LQRSV was identified in 22 athletes (11.4%), with a higher prevalence among those with SCI (27.6% vs. 4.6% in NSCI, p < 0.0001). Athletes with LQRSV were older (p = 0.01), frequently involved in skill-based sports (p < 0.0001). Compared with athletes with normal ECG voltages, they exhibited reduced exercise performance (VO2 max 23.1 ± 10.5 vs. 37 ± 14.5 ml/min/kg; p < 0.0001) and lower O2 pulse (p < 0.0001). Echocardiography revealed smaller left ventricular (LV) volumes and LV mass, while systolic function was preserved (p = 0.488). Among SCI athletes, those with LQRSV demonstrated lower W/kg (p = 0.039), lower LV mass (p = 0.037) and higher fat mass (p = 0.035). At multivariable logistic regression analysis, SCI emerged as the only independent correlate of LQRSV (p = 0.011).

LQRSV shows an unexpectedly high prevalence in PA, particularly those with SCI, and may reflect a cardiac phenotype characterized by smaller chambers and reduced metabolic drive, rather than pathological remodeling.