Transplantation for idiopathic pulmonary arterial hypertension: improvement in the lung allocation score era

Abstract

Background: Lung transplantation and heart-lung transplantation represent surgical options for treatment of medically refractory idiopathic pulmonary arterial hypertension. The effect of the lung allocation score on wait-list and transplantation outcomes in patients with idiopathic pulmonary arterial hypertension is poorly described.

Methods and results: Adults diagnosed with idiopathic pulmonary arterial hypertension and listed for transplantation in the 80 months before and after the lung allocation score algorithm was implemented (n=1430) were identified in the United Network for Organ Sharing thoracic registry. Patients were stratified by organ listed and pre- and post-lung allocation score era. The cumulative incidences of transplantation and mortality for wait-listed patients in both eras were appraised with competing outcomes analysis. Posttransplantation survival was assessed with the Kaplan-Meier method. These analyses were repeated in propensity-matched subgroups. Cox proportional hazards analysis evaluated the effect of prelisting and pretransplantation characteristics on mortality. We found that patients in the post-lung allocation score era had significantly worse comorbidities; nevertheless, both lung transplantation and heart-lung transplantation candidates in this era enjoyed lower wait-list mortality and a higher incidence of transplantation in unmatched and propensity-matched analyses. On multivariable analysis, heart-lung transplantation and double-lung transplantation were associated with improved survival from the time of wait-listing, as was being listed at a medium- to high-volume institution. Donor/recipient sex matching predicted posttransplantation survival.

Conclusions: The incidence of transplantation has increased while wait-list mortality has decreased in patients with idiopathic pulmonary arterial hypertension wait-listed for transplantation in the post-lung allocation score era. Both heart-lung transplantation and double-lung transplantation are predictive of survival in transplantation candidates with idiopathic pulmonary arterial hypertension, as is being listed at a medium- to high-volume institution. Donor/recipient sex matching is associated with better posttransplantation survival.

Keywords: hypertension; hypertension, pulmonary; statistics; survival; transplantation.