Assessment of Left Atrial Function in Hypertrophic Cardiomyopathy and Athlete's Heart: A Left Atrial Myocardial Deformation Study

Background: Hypertrophic cardiomyopathy (HCM) is a common cause of sudden death in athletes and differentiating this condition from the nonpathological athlete's heart remains a challenge. The development of pathological left ventricular hypertrophy (LVH) is associated with left atrial (LA) dilatation and dysfunction. LA strain and strain rate by two-dimensional (2D) speckle tracking are novel indices of LA function and might contribute to differentiate physiological from pathological LVH among athletes with underdiagnosed HCM. Methods: We evaluated 20 patients with nonobstructive HCM, 20 highly trained athletes and 20 healthy controls matched for age, gender, and body surface area. All patients underwent a transthoracic echocardiogram with evaluation of LA strain: s-wave (LASs); and strain rate: s-wave (LASRs) and a-wave (LASRa). Results: LV mass index, LA volume index, and ejection fraction were comparable between patients with HCM and athletes. Patients with HCM had a significantly lower LASs (19 + 8% vs. 43 + 8%, P < 0.01), LASRs (0.7 + 0.2 s-1 vs. 1.6 + 0.2 s-1, P < 0.01), and LASRa (0.8 + 0.1 s-1 vs. 1.4 + 0.3 s-1, P < 0.01) compared to athletes. Among hypertrophic subjects, independent predictors of hypertrophy related to HCM were LASs and E/e ratio. Conclusions: LA myocardial deformation is significantly impaired in patients with HCM compared to athletes and healthy controls. LA strain and strain rate assessed by 2D speckle tracking should be incorporated in the evaluation of trained athletes with LVH and LA dilatation.