Right ventricular myocardial involvement in either physiological or pathological left ventricular hypertrophy: an ultrasound speckle-tracking two-dimensional strain analysis.

Aims: To analyse right ventricular (RV) myocardial deformation in patients with left ventricular (LV) hypertrophy secondary to either hypertrophic cardiomyopathy (HCM) or athlete's competitive endurance training.
Methods and Results: Standard Doppler echo, exercise stress echo, and 2D speckle-tracking strain echocardiography (2DSE) of RV longitudinal deformation in RV septal and lateral walls were performed in 50 top-level endurance athletes and in 35 patients with HCM, all men, having evidence of LV hypertrophy. Right ventricular global longitudinal strain (GLS) was calculated by averaging local strains along the entire right ventricle. The two groups were comparable for age and blood pressure, whereas athletes showed lower heart rate and increased body surface area than HCM. Interventricular septal thickness was higher in HCM, whereas both LV and RV end-diastolic diameters (LVEDD and RVEDD) and LV stroke volume were increased in athletes. Right ventricular tricuspid annulus systolic excursion was comparable between the two groups. Conversely, RV GLS and regional peaks of RV myocardial strain were significantly impaired in patients with HCM (all P < 0.001). Multiple linear regression models detected an independent association between RV GLS and LVEDD (beta-coefficient = -0.68, P < 0.0001) in athletes, as well as an independent correlation of the same RV GLS with septal thickness (beta = 0.63, P < 0.0001) in HCM. An RV GLS cut-off value of -0.16% differentiated athletes and HCM with an 86% sensitivity and a 92% specificity. Furthermore, in the overall population, RV GLS (beta = 0.51, P < 0.0001) was a powerful independent predictor of maximal workload during exercise stress echo.
Conclusion: Right ventricular myocardial systolic deformation is positively influenced by preload increase in athletes and negatively associated with increased septal thickness in HCM. Therefore, 2DSE may represent a useful tool in the differential diagnosis between athlete's heart and HCM, underlining the different involvement of RV myocardial function in either physiological or pathological LV hypertrophy.