Echocardiographic right-ventricular global wasted work predicts hemodynamics and risk profile in pulmonary arterial hypertension

Aims Novel echocardiographic indices of right ventricular myocardial work (RVMW) are gaining ground for the evaluation of pulmonary arterial hypertension (PAH). However, their role in predicting hemodynamics and risk profile remains unclear. This study aimed to assess whether RVMW indices can identify patients at high risk for mortality and those with a worse hemodynamic profile as determined by right heart catheterization (RHC). Methods & Results Patients with PAH, confirmed by RHC, with available echocardiographic images for RVMW estimation were analysed. Patients’ risk profile was determined according to guidelines. RVMW indices were measured and correlated with four RHC parameters (mean pulmonary artery pressure [mPAP], pulmonary vascular resistance [PVR], stroke volume index [SVI], pulmonary arterial compliance [PAC]). RVMW analysis was completed in 58 PAH patients (58±14 years old, 72% female). RV global wasted work (RVGWW) was significantly increased, while RV global work efficiency (RVGWE) was significantly decreased in the ‘high risk’ group. RVGWW correlated with mPAP (R=0.46; p <0.001), PVR (R=0.51; p <0.001), SVI (R=-0.3; p=0.024) and PAC (R=-0.31; p=0.02). Specific cut-off values of RVGWW emerged as predictors of worse hemodynamics based on spline curves; <60 mmHg % indicated low-probability of PVR >5 WU, >83-84 mmHg % indicated high-probability of PAC <2.3 ml/mmHg and mPAP >40 mmHg, >120 mmHg % indicated SVI <31 ml/m2 in RHC. Furthermore, RVGWW values >175 mmHg % were associated with patients at high-risk for mortality. Conclusion RVGWW correlated well with invasive hemodynamic parameters and was found to predict a worse hemodynamic and high-risk profile in a prospective cohort of PAH patients.