Global and Regional Right Ventricular Dysfunction in Pulmonary Hypertension

Abstract

Pulmonary hypertension (PH) is known to affect the right ventricular (RV) function. To assess the extent of global and regional RV dysfunction in PH patients. We performed a cross-sectional study on 20 controls (age 62 ± 15 years, 7 males) and 35 patients (age 67 ± 12 years, 13 males) with PH of mixed etiologies and assessed RV inflow and outflow tracts (OTs) function, using speckle tracking echocardiography (STE) based myocardial deformation and its time relations. RV inlet and OT dimensions (2D), inlet myocardial velocities (TDI), myocardial strain and strain rate (SR), TAPSE (M-mode), ejection and filling times (pulsed-wave [PW] Doppler), and pulmonary artery acceleration (PAc) were measured. RV inlet and OT were dilated (P < 0.001 for both) and TAPSE (P < 0.001), inlet velocities (P < 0.001), basal and mid-cavity strain, SR and longitudinal displacement reduced (P < 0.001 for all). The time to peak systolic SR at basal, mid-cavity (P < 0.001 for both), and RVOT (P = 0.007) was short as was that to peak displacement (P < 0.001 for all). The time to peak pulmonary ejection correlated with time to peak SR at RVOT (r = 0.7, P < 0.001) in controls, but with that of the mid-cavity in patients (r = 0.71, P < 0.001). PAc was faster (P = 0.001) and RV filling time shorter in patients (P = 0.03) with respect to controls. PH has drastic effects on RV structure and intrinsic myocardial function, significantly disturbing its ejection time relations and overall pump performance. Increased RV afterload results in RV configuration changes with the inflow tract determining peak ejection rather than OT.