Left ventricular vorticity is marker of ventricular interdependency in pulmonary arterial hypertension

Background Chronic right ventricular (RV) pressure and volume overload in pulmonary arterial hypertension (PAH) results in leftward shift of the interventricular septum and impaired left ventricular (LV) diastolic function. However, the impact of PAH-mediated interdependency on LV fluid mechanics and fluid/structure interactions in LV diastolic dysfunction is incompletely understood. 4D flow CMR analysis of LV inflow has demonstrated vortical formations during early (E wave) and late (A wave) filling. Vorticity is a novel hemodynamic parameter describing the local spinning nature of the fluid elements that measures the rotation of these vortices and may represent a novel way to assess the impact of interdependency on LV diastolic flow and function. Using LV systolic eccentricity index (EI) and diastolic tissue Doppler measurements as markers of ventricular interdependency, we aimed to determine if LV vorticity correlated with indices of interdependency in PAH subjects and controls.