Abstract 19236: Effect of Continuous Flow Left Ventricular Assist Device on Diastolic Pulmonary Artery Pressure-to-Pulmonary Capillary Wedge Pressure Gradient in End Stage Heart Failure Patients with Pulmonary Hypertension

Background: Continuous flow left ventricular assist devices (LVAD) reduces transpulmonary gradient (TPG) and pulmonary vascular resistance (PVR) in end-stage HF patients with pulmonary venous hypertension (PVH). However, TPG and PVR are flow dependent and may not reflect intrinsic pulmonary vascular remodeling. Diastolic pulmonary artery pressure-to-pulmonary capillary wedge pressure gradient (DPG) has been shown to more accurately reflect pulmonary vascular remodeling. Objective: We sought to evaluate the effect of LVAD on DPG in end-stage HF patients with PVH (mPAP > 25 mm Hg and PCWP > 15 mm Hg). Methods: We retrospectively reviewed clinical and hemodynamic data on 116 end-stage HF patients with PVH who underwent LVAD implantation and analyzed changes in DPG between pre- and first post-LVAD right heart catheterization (RHC). Results: The mean age was 55 ± 14 years and 78% were males. Of the 116 patients, 83 patients had pre-LVAD DPG 7 mm Hg (Combined post-and pre-capillary PVH). The median duration between the pre-and post-LVAD RHC was 147 (IQR: 106-302) days. Table below compares pre-and post-LVAD hemodynamics. In patients with combined post-and pre-capillary PVH, LVAD therapy significantly decreased DPG (9 ± 4 vs. 6 ± 6; P<0.001). However, 42% of these patients did not lower DPG to <7 mmHg with LVAD therapy (non-responders). On multivariate regression, higher pre-LVAD DPG was the only independent factor associated with non-responders. Pre-LVAD DPG >8 mm Hg had 77% sensitivity and 88% specificity for identifying non-responders (AUC 0.82). Conclusion: Although DPG decreased after LVAD therapy, it remained significantly elevated (>7mm Hg) in a subset of patients with combined post-and pre-capillary PVH. DPG >8 mm Hg is significantly associated with non-response to LVAD therapy. Additional studies are warranted to assess the impact of these findings on outcomes.