Abstract 9797: Right Ventricular Function Can Predict Transplant-Free Survival in Patients with Pulmonary Arterial Hypertension

Abstract

Background Timely identification of patients with the need for transplantation (Tx) due to severe pulmonary arterial hypertension (PAH) and finding predictors of Tx-free outcome are becoming increasing challenges with prolongation in Tx waiting times. Right ventricular (RV) failure is the main cause of death in PAH. We assessed the predictive value of RV function for Tx-free survival in severe PAH to improve the Tx listing procedures. Methods All consecutive potential Tx candidates with PAH (except those with congenital systemic to pulmonary shunts) who were clinically stable at their first evaluation performed in 2006─2010 were selected for the study. At selection, after NT-ProBNP measurement and exercise testing, patients underwent echocardiography including 2D strain imaging. All examinations were repeated at each further follow-up. Collected data were tested for ability to predict Tx-free survival. Results Of 64 evaluated patients, 19 showed irreversible RV failure and finally 13 patients died; the other 6 underwent Tx. Comparing data obtained from these 19 patients at time of inclusion in the study with those obtained initially from the 45 patients remaining stable, we found no differences in RV size and RVEF, pulmonary arterial pressure, right atrial size and tricuspid annulus plane systolic excursion (TAPSE). However, patients with subsequent worsening had initially higher NT-proBNP values and lower RV ΔP/Δt ratios (p < 0.05). In unstable patients, RV longitudinal strain analysis also revealed higher systolic dyssynchrony, lower systolic afterload-corrected strain rate (Sr) and higher diastolic early/late strain rate (SrE/SrA) ratio (p<0.05). At certain cut-off values, ΔP/Δt and SrE/SrA ratios showed the highest predictive values (93.3% and 91.1%, respectively) for ≥ 1 year hemodynamic stability. Persistent RV ΔP/Δt reduction of > 20% showed the highest predictive values for short-term (< 1year) irreversible RV failure and patient Tx-free survival (90% and 93.3%, respectively). Conclusion In PAH patients referred for Tx, RV ΔP/Δt and certain longitudinal Sr parameters are predictive for the short-term course of RV function and patient Tx-free survival. Our results suggest that these parameters can be useful for Tx listing decisions.