Impact of abnormal longitudinal rotation on the assessment of right ventricular systolic function in patients with severe pulmonary hypertension

Background: Assessment of right ventricular (RV) function plays an important role in patients with cardiopulmonary disease, and current guidelines recommend parameters including tricuspid annular plane systolic excursion (TAPSE) and right ventricular systolic excursion velocity (RVS') to assess RV longitudinal function. We assessed the hypothesis that the previously undescribed motion of RV longitudinal rotation (RVLR) is an independent predictor of both TAPSE and RVS'. Methods: We assessed a series of 100 consecutive patients with pulmonary hypertension (PH) undergoing echocardiography. Patients with left ventricular (LV) dilation and dysfunction were excluded. Standard RV parameters were determined using established guidelines, while RVLR and right ventricular global longitudinal strain (RVGLS) measurements were performed using 2-dimensional (2D) speckle tracking technique. Results: Mean peak RVLR measured -4.2 +/- 3.7 degrees. By convention, negative values implied clockwise motion. In a multiple linear regression model, TAPSE could be predicted from a combination of RVLR and RVGLS (R=0.56, P<0.(X)1). A similar relationship was found for RVS' which could also be predicted from a combination of RVLR and RVGLS (R=0.52, P<0.001). While no association was found between RVLR and RV size, estimated RV systolic pressure (RVSP) or the presence of a pericardial effusion, a mild correlation was noted between RVLR and QRS duration (R=0.25, P=0.01). Conclusions: RVLR is an independent predictor of TAPSE and RVS'. Awareness of this motion should be considered in the interpretation of TAPSE and RVS' values as markers of RV systolic function, as abnormal RVLR may account for exaggerated values, particularly in patients with PH and RV dysfunction.