Imaging Criteria by Echocardiography for Detection of Hypertrophic Cardiomyopathy in Elite Athletes

Abstract

BACKGROUND Over the past few years, the number of sudden cardiac deaths in young elite athletes has been remarkable. Unfortunately, screening for hypertrophic cardiomyopathy (HCM) is not mandatory in professional sports. Echocardiography remains the primary tool for assessing left ventricular (LV) structure and function. Therefore, we applied echocardiography to test whether echocardiography-derived variables accurately distinguish HCM from other variants of LV hypertrophy. METHODS A total of 82 subjects were enrolled and distributed into four groups, which comprised healthy controls (HC), professional athletes, patients with hypertensive LV hypertrophy (HTN-LVH), and patients with HCM. All subjects were men. LV ejection fraction (LVEF) was preserved in all subjects. For each subject, 16 echocardiographic parameters of LV function and five parameters of LV structure were obtained and referenced against internationally recognized parameters. Speckle-tracking echocardiography was performed to obtain global longitudinal strain (GLS). RESULTS Elite athletes were found to have significantly (p<0.05) lower LV mass index, septal wall thickness, relative wall thickness, and LV posterior wall thickness than HCM patients. Among patients with HTN-LVH, athletes also had significantly lower septal wall thickness. With respect to echocardiographic variables associated with LV function, elite athletes had significantly lower left atrial (LA) volume index, GLS, and septal tissue Doppler imaging (TDI) E/e’ ratio and higher TDI e’ velocity than HCM patients. Among HTN-LVH patients, TDI e’ velocity was also significantly higher and TDI E/e’ was significantly lower in elite athletes. On the receiver operating characteristic curve analysis, LV mass index >122.2 g/m2 (area under the curve [AUC]=0.921; p<0.001), LA volume index >34.73 ml/m2 (AUC=0.937; p<0.001), septal TDI E/e’ ratio >11.57 (AUC=0.866; p<0.001), and GLS <0.001) were variables distinguishing HCM among elite athletes. CONCLUSIONS LV mass index, LA volume index, TDI E/e’ ratio, and GLS were found to be more strongly associated with HCM. Therefore, we recommend that athletes with LVH in whom these echocardiographic variables exceed the cutoff values (as found in our population) should undergo comprehensive cardiovascular assessment before undertaking strenuous exercise. KEYWORDS Athlete’s heart; Echocardiography; Hypertrophic cardiomyopathy; Global longitudinal strain; Left ventricular hypertrophy ABBREVIATIONS 2D, two-dimensional; ANOVA, one-way analysis of variance; GLS, global longitudinal strain; HCM, hypertrophic cardiomyopathy; HTN, hypertension; LA, left atrial; LV, left ventricular; LVEF, left ventricular ejection fraction; LVH, left ventricular hypertrophy; MRI, magnetic resonance imaging; ROC, receiver operating characteristic; TDI, tissue Doppler imaging