60 Ethnic differences in repolarisation patterns and left ventricular remodelling in highly trained male adolescent (14-18 years) athletes

Abstract

Introduction: Studies in adult black athletes (BA) demonstrate a high prevalence of ECG repolarisation changes and echocardiographic left ventricular hypertrophy (LVH) that may overlap with hypertrophic cardiomyopathy (HCM). The prevalence of ECG repolarisation changes and echocardiographic LVH in adolescent BA, the group most vulnerable to exercise-related sudden death from HCM, is unknown. Methods: This study evaluated 219 male adolescent BA (14-18 years, inclusive) with 12-lead ECG and 2-D echocardiography. Results were compared with 1 440 male adolescent WA. Athletes with T-wave inversions and morphological LVH were invited for further investigation with an exercise stress test, 24-hour Holter and CMR. Results: ST-segment elevation was common in both groups but more frequent in BA (63.5 vs 14.9%, p < 0.001), while ST-segment depression was exceedingly rare. Both T-wave inversions (21.5 vs 2.9%, p < 0.001) and deep T-wave inversions (11 vs 0.3%, p < 0.001) were commoner in BA. Black athletes demonstrated greater left ventricular wall thickness (10.4 ± 1.6 vs 9.4 ± 1.2 mm, p < 0.001) compared to WA. Twenty-three (10.5%) BA exhibited a left ventricular wall thickness > 12 mm versus only six (0.4%) WA (p < 0.001) showing a similar thickness. None of the athletes exhibited the broader phenotype of HCM on further investigation. In multivariable analysis, black ethnicity was the strongest independent predictor for the presence of T-wave inversions (OR 3.56, 95% CI: 1.56-8.13, p = 0.003) and LVH (OR 3.17, 95% CI: 1.77-5.71, p < 0.001). Conclusions: As with adult athletes, T-wave inversions and LVH were more prevalent in adolescent BA compared to WA. These findings have important implications in the pre-participation screening era, particularly in countries with a high proportion of BA competing at elite levels, since extrapolation of ECG and echocardiographic criteria, solely derived from Caucasian cohorts, would result in 25.6% of BA requiring further investigations for cardiac pathology.