Mechanical circulatory support is effective to treat pulmonary hypertension in heart transplant candidates disqualified due to unacceptable pulmonary vascular resistance

Abstract

Introduction: High pulmonary vascular resistance (PVR) in orthotopic heart transplantation (OHT) candidates is a risk factor of right ventricle failure after the procedure. However, the increase of PVR may be a consequence of the life-threatening deterioration of the left ventricle function. The use of mechanical circulatory support (MCS) seems to be the best solution, but it is reimbursed only in active OHT candidates. Aim: We performed a retrospective analysis of MCS effectiveness in maintaining PVR at values accepted for OHT. Material and methods: Starting from the year 2008 we identified 6 patients (all males, 42.8 ±17 years old) with dilated (n = 3), ischemic (n = 2), and restrictive cardiomyopathy (n = 1) in whom MCS - pulsatile left ventricle assist device (LVAD, n = 4), continuous flow LVAD (n = 1), and pulsatile biventricular assist device (BIVAD, n = 1) - was used at a time when PVR was unacceptable for OHT, and the reversibility test with nitroprusside was negative. After an average time of support of 261 ±129 days they were all transplanted. Results: Right heart catheterization (RHC) results before MCS implantation were as follows: Pulmonary artery systolic, diastolic, and mean pressure (PAPs/d/m) 60 ±20/28 ±7/40 ±11 mm Hg, pulmonary capillary wedge pressure (PCWP) 21 ±7 mm Hg, transpulmonary gradient (TPG) 19 ±7 mm Hg, cardiac output (CO) 3.6 ±0.8 l/min, PVR 5.7 ±2.1 Wood units (WU). Right heart catheterization results during MCS therapy were as follows: PAPs/d/s 27 ±11/12 ±4/17 ±6 mm Hg, PCWP 10 ±4 mm Hg, TPG 7 ±4 mm Hg, CO 5.1 ±0.7 l/min, PVR 1.4 ±0.6 WU. None of the patients experienced right ventricle failure after OHT with only one early loss due to multiorgan failure. Conclusions: Mechanical circulatory support is an effective method of pulmonary hypertension treatment for patients disqualified for OHT due to high PVR.