A useful scoring system for predicting right ventricular assist device requirement among patients with a paracorporeal left ventricular assist device

Ventricular assist devices (VADs) have become an important therapy for advanced heart failure, however, the prognosis of those who receive a biventricular assist device (BiVAD) is still poor. We enrolled 70 patients who underwent paracorporeal VAD (Nipro-VAD®) implantation between 2004 and 2015 and studied the preoperative risk factors, including hemodynamic parameters for RVAD requirement. Furthermore, 2-year survival was compared between the BiVAD group and LVAD only group. Fourteen patients (20%) required RVAD. The BiVAD group had a significantly smaller left ventricular diastolic/systolic dimension, lower mean pulmonary artery wedge pressure (PAWP), lower cardiac index (CI), higher pulmonary vascular resistance (PVR), higher mean right atrial pressure (RAP), lower pulmonary artery pulsatility index (PAPi), lower right ventricular stroke work index (RVSWI), and higher mean RAP/mean PAWP ratio preoperatively. After multivariate analysis, only PVR > 4.5 Wood units: WU (P = 0.013, odds ratio: OR 7.9) and mean RAP/mean PAWP > 0.8 (P < 0.001, OR 14.4) were significant predictors for RVAD requirement. From these odds ratios, we assigned 1 point to PVR > 4.5 WU and 2 points to mean RAP/mean PAWP > 0.8. This simple scoring method adequately stratified the incidence of RVAD implantation (score 0: 4.4%, score 1: 28.6%, score 2: 41.7%, score 3: 83.3%). The cumulative survival rate at 2-year after VAD implantation was significantly worse among patients who required RVAD support compared to the LVAD only group (28.5% versus 74.4%, P = 0.009). RVAD requirement is associated with poor long-term survival, and this simple scoring system using PVR and mean RAP/mean PAWP may be useful for predicting RVAD requirement in such patients.