Normalization of high pulmonary vascular resistance with LVAD support in heart transplantation candidates

Objective: Pulmonary hypertension (PH) and elevated pulmonary vascular resistance (PVR) lead to poor outcome after heart transplantation due to postoperative failure of the non-conditioned right ventricle. The role of continuous flow left ventricular assist device (LVAD) support in the reduction of elevated PVR was evaluated in a series of clinical implants. Methods: Among 17 patients with terminal heart failure receiving a MicroMed DeBakey LVAD as bridge to transplant, there were six patients with pulmonary hypertension (mean systolic PAP 47mmHg) and high PVR (398dynes/cm5), previously not considered suitable for heart transplantation, who underwent serial right heart catheters during their LVAD support period. Results: In these patients mean systolic pulmonary pressure dropped to 29mmHg and PVR decreased to a mean 167dynes/cm5 under LVAD support. Clinical improvement was significant in all patients. Four patients were successfully transplanted without major postoperative difficulties (mean duration 130 days support) and all are doing well to date. Post-transplant-PVR remained in the normal range in all transplanted patients. Conclusions: Elevated PVR and severe PH were both previously considered as contraindication for heart transplantation. A period of LVAD pumping leads to a progressive decrease of PVR and normalization of pulmonary pressures, making these patients amenable for heart transplantation. LVAD as bridge to heart transplantation is safe and highly beneficial for terminal heart failure patients with severe PH.