Surrogates of right ventricular - pulmonary artery coupling in the prediction of heart failure compensation and survival after implantation of left ventricular assist device

Introduction The right ventricle (RV) performance is one of the main factors conditioning effectiveness of the left ventricular mechanical support. Determination of the real potential of RV functionality in a state of left ventricle failure, as well a determination of the probability of RV failure after left ventricular assist device (LVAD) implantation is challenging. For objectification of the RV functionality assessment, the right ventricle – pulmonary artery (RV-PA) coupling evaluation was introduced. Purpose The aim of the study was evaluation of the usefulness of RV-PA coupling in prediction of heart failure (HF) compensation and survival after LVAD implantation. Methods The study involved 119 consecutive patients with LVADs implanted in the years 2013 – 2025. HF was evaluated one year after the surgery, on the basis of NTproBNP concentration (uncompensated HF: NTproBNP ≥ 3000 pg/ml; compensated HF: NTproBNP < 3000 pg/m). RV function was assessed with use of standard echocardiographic parameters, right heart catheterization and indirect indicators of RV-PA coupling: TAPSE/RVSP, FAC/RVSP, TAPSE/PAAT, TAPSE/sPAP, TAPSE/PVR, TAPSE/TPG, mRAP/mPCWP, RVP-RAP difference, PVR/SVR, and RVCPI [right ventricular contraction pressure index as TAPSE*(RVP-RAP)]. As a normal distribution criteria were not met, the nonparametric tests (Mann-Whitney, Wilcoxon, chi2) were used for statistical analysis. The survival analysis was performed with the log-rank test. As the statistically significant p < 0,05 was assumed. Results Parameters of RV function and RV-PA coupling indicated deterioration of RV function after LVAD implantation. Concentration of NTproBNP was significantly lower after LVAD implantation (p < 0,01). NTproBNP concentration was significantly higher in patients who died after LVAD implantation (p=0,01). Value of the most analysed parameters did not differ between patients with compensated and noncompensated HF as well in range of survival rates (respectively): TAPSE/RVSP (p=0,8 and p=0,99), FAC/RVSP (p=0,76 and p=0,9), TAPSE/PASP (p=0,2 and p=0,08), TAPSE/PVR (p=0,45 and p=0,63), TAPSE/TPG (p=0,78 and p=0,15), RA/PCWP (p=0,89 and p= 0,38), RV-RA (p=0,77 and p= 0,72), RVCPI (p= 0,63 and p=0,12), SVR/PVR (p=0,23 and p= 0,72), with the exception of TAPSE (p=0,13 and p=0,02) and TAPSE/PAAT (p=0,05 and p=0,01). Conclusions Despite the worsening of most of RV function parameters after LVAD implantation, improvement in the compensatory state of HF was achieved. Mortality was directly related to NTproBNP concentration and HF compensatory state, not with most of RV and RV-PA coupling parameters, with the exception of TAPSE and TAPSE/PAAT. Taking into account a multiplicity of analysed parameters, the achieved results suggest a lack of unique factors, which would let to determination of the effectiveness of LVAD support before its implantation. The role of TAPSE/PAAT requires further verification.