Left Ventricular Assist Devices or Inotropes for Decreasing Pulmonary Vascular Resistance in Patients with Pulmonary Hypertension Listed for Heart Transplantation

Background: Fixed pulmonary hypertension is common in patients with advanced heart failure and is a contraindication for heart transplantation. Left ventricular assist devices (LVAD) and inotropes have been used to reduce pulmonary vascular resistance (PVR) and allow transplantation. However, little is known about the efficacy of this strategy.

Methods: We queried the United Network for Organ Sharing registry for all adult patients (age ≥18 years) listed for primary heart transplantation (2008-2014) with PVR of >5 wood units (WU) or transpulmonary gradient >16 mmHg who were treated with LVAD or IV inotropes as status 1a, 1b, or 7. We compared waitlist mortality/delisting and absolute changes in hemodynamics between listing and transplantation.

Results: Of 18,009 patients listed during the study period, 1016 were included in the analysis (393 LVAD, 623 inotropes), with a mean age of 52.9 ± 11.6 years, 74% male, and 38% had ischemic etiology. Mean PVR was 5.7 ± 2.4 WU and transpulmonary pressure gradient 19.3 ± 5.3 mmHg. Compared with the inotrope group, LVAD patients were more likely listed as status 1A (32.8% vs 18.1%, P < .001), had lower PVR (5.3 WU vs 5.9 WU, P = .001), and higher cardiac output (4.1 vs 3.6 L/min, P < .001). After a mean of 239 days, PVR decreased by 1.71 WU in the LVAD group vs 1.85 WU in the inotrope group (P = .52). PVR normalization (<2.5 WU) occurred at similar rates among those treated with inotropes and LVAD (30.7% vs 35.6%, P = .228). Waitlist mortality was similar between LVAD and inotropes (adjusted P = .837). Absolute PVR and transpulmonary pressure gradient reductions correlated with time on the waitlist (P < .001 for both comparisons).

Conclusion: Only about one-third of patients with fixed pulmonary hypertension achieve normalization of PVR before transplant with either LVAD or inotropes. Similar waitlist mortality was observed among patients bridged with either strategy.