Comparative outcomes of bilateral lung and heart-lung transplantation in primary pulmonary arterial hypertension: A UNOS database study.

BACKGROUND

In end-stage primary pulmonary arterial hypertension (PAH), chronically elevated pulmonary vascular resistance leads to right ventricular hypertrophy, dilation, and failure, complicating transplant decision-making. Surgical options include bilateral lung and heart-lung transplantation, but the optimal strategy remains debated.

METHODS

We conducted a retrospective cohort study using the Organ Procurement and Transplantation Network to identify adults (≥18 years) who underwent bilateral lung or heart-lung transplantation for PAH between June 30, 2004, and September 30, 2022. Patients with congenital or structural cardiac abnormalities were excluded. Baseline demographics, comorbidities, hemodynamics, perioperative course, and survival were compared by transplant type. The primary outcome was 1-year mortality; the secondary outcome was 5-year mortality.

RESULTS

Of 914 PAH recipients, 776 (84.9%) underwent bilateral lung transplantation and 138 (15.1%) underwent heart-lung transplantation. Bilateral lung recipients had higher cardiac index (2.4 vs 2.2 liter/min/m², p = 0.02) and lower pulmonary capillary wedge pressure (11 vs 13 mm Hg, p < 0.001). They were more likely to require extracorporeal membrane oxygenation at 72 hours (24.2% vs 10.8%, p = 0.02) and remain intubated (43.0% vs 23.9%, p < 0.001). Survival was similar between groups. Heart-lung transplantation was not associated with increased mortality at 1 year (adjusted hazard ratio 1.82, 95% cardiac index 0.89-3.71, p = 0.10) or 5 years (hazard ratio 1.49, 95% cardiac index 0.87-2.54, p = 0.14). Findings were consistent across hemodynamic subgroups.

CONCLUSIONS

In PAH, bilateral lung transplantation achieves comparable 1- and 5-year survival to heart-lung transplantation, supporting its role as a viable alternative in appropriately selected patients.