Transplant outcomes for pulmonary arterial hypertension

<bold>Background:</bold> End-stage PAH and associated cardiac remodeling raise concern about RV recovery after lung transplant. The use of combined heart-lung vs. bilateral-lung transplant is subject to debate. <bold>Objective:</bold> Compare survival of PAH transplant recipients of bilateral-lung vs. combined heart-lung transplant. <bold>Methods:</bold> Using the Organ Procurement and Transplantation Network data, we included adults without congenital or structural cardiac abnormalities who were transplanted between 6/30/2004 and 9/30/2022 for PAH. Demographics, comorbidities, baseline hemodynamics, surgical characteristics, survival, and graft failure were compared by transplanted organs. The primary outcome was 1-year survival. Secondary outcomes included 5-year survival and graft failure. <bold>Results:</bold> 918 patients were included; 777 (84.6%) received a bilateral lung transplant, while 141 (15.4%) received a heart-lung transplant. Pre-transplant mPAP and PVR were similar. Cardiac output was higher among bilateral-lung recipients (4.3 vs. 3.8 L/min, P< 0.001), and PCWP was lower (11 vs. 13 mmHg, P<0.001). More heart-lung recipients received ECMO before transplant (20.6% vs. 9.0%, p<0.001), and bilateral-lung recipients had a higher median ischemic time (5.5 vs. 3.8 hrs, p<0.001). Overall mortality was higher in heart-lung recipients (53.9% vs. 42.7%); 1-year (log-rank P=0.24) and 5-year survival (log-rank P=0.80) did not differ between groups. Graft survival did not differ at one year (log-rank P=0.19) or five years (log-rank P=0.62). <bold>Conclusion:</bold> Compared to bilateral-lung recipients, heart-lung recipients had lower cardiac output, increased PCWP, and increased use of ECMO. There was no significant difference at 1- and 5-year overall or 5-year graft survival.