3D Echo Derived Right Ventricular Principal Surface Strain in Pulmonary Arterial Hypertension.

Overview

abstract

Background. Traditional echocardiographic metrics of right ventricular (RV) function including tricuspid annular plane systolic excursion (TAPSE) and 2-dimensional (2D) strain are limited to the description of longitudinal systolic function. These metrics however fails to account for the complex, 3-dimensional (3D) deformation of the RV. Methods. 3D echocardiograms (3DE) were obtained simultaneous during clinically indicated right heart catheterization (RHC). We determined the maximum principal surface strain (PS_Max) and angle (ϴ_Max) of RV surface deformation in PAH and control patients. Results. We compared 22 control patients to 37 patients with PAH, of whom 11 met hemodynamic criteria for right heart (RH) failure. Compared to 2D descriptors of RV function, PS_Max was significantly different between controls and PAH patients and between PAH patients with and without RH failure. ϴ_Max was oriented progressively longitudinally in PAH patients without RH failure compared PAH patients with RH failure [37.5(34.3 - 40.8)˚ vs. 34.3(32.1 - 36.2)˚, p=0.042] and in PAH patients with worse NYHA functional class. 30-day outcomes were significantly different with an optimal cutoff of PS_Max of -21.4%, with a hazard ratio of 6.8 (95% CI 1.3 to 35.2, p=0.022). Conclusion. PS_Max is a robust marker of RH failure and provides prognostic value in PAH beyond conventional 2D descriptors of RH function. Progressive longitudinal deformation of ϴ_Max is associated with worse RH function and functional class.