Pulmonary Vascular Reverse Remodeling in Combined Post and Pre Capillary Pulmonary Hypertension Occurs Over Time after Left Ventricular Assist Device Implantation

Purpose Left ventricular assist device (LVAD) has been reported to improve pulmonary hypertension (PH) due to left heart disease (PH-LHD). However, prevalence of combined post- and pre-capillary PH (Cpc-PH) in patients with PH-LHD and the impact of LVAD implantation on Cpc-PH has not been fully elucidated. This study aimed to investigate hemodynamic changes following LVAD implantation in patients with PH-LHD to assess pulmonary vascular reverse remodeling. Methods Eighty-nine patients with advanced heart failure complicated by PH-LHD undergoing LVAD implantation who received serial right heart catheterizations at least 3 time points (before, early after, and 1-year after implantation) were retrospectively reviewed. Patients were divided into 2 groups as Cpc-PH group (n=50): pulmonary vascular resistance (PVR) > 3 Wood unit (WU) or diastolic pulmonary pressure gradient (DPG) ≥ 7 mmHg, and isolated post-capillary PH (Ipc-PH) group (n=39). Results Values of brain natriuretic peptide and transaminase in Cpc-PH group were higher than those in Ipc-PH group. Cpc-PH patients were consisted of 41 with PVR > 3 WU, 8 with PVR > 3 WU and DPG ≥ 7 mmHg, and 1 with DPG ≥ 7 mmHg preoperatively. Median values of PVR in both groups significantly decreased early after LVAD implantation [from 4.1 to 2.7 WU (p 3 WU (n=14) or DPG ≥ 7 mmHg (n=1) at that point. Among these 15 patients, 4 patients still remained on their PVR > 3 WU (n=3) or DPG ≥ 7 mmHg (n=1) even 1-year after LVAD implantation. PVR and DPG in these 4 patients turned to normal values at 3-year after implantation. Conclusion Over half of patients with PH-LHD were complicated by Cpc-PH in our study cohort. LVAD implantation readily improved hemodynamics regardless of complication of Cpc-PH, whereas 15 patients were still found to be PVR > 3 WU or DPG ≥ 7 mmHg which should be considered as persistent Cpc-PH. We speculate that most of Cpc-PH in patients with PH-LHD might be caused by alteration of vascular tone which will be promptly relieved by substantial left ventricular unload, however a certain number of patients with Cpc-PH might develop structural remodeling of pulmonary vasculature which requires months or years to achieve pulmonary vascular reverse remodeling.