Not all septal defects are equal. Outcomes of Bilateral Lung Transplant with Cardiac Defect Repair vs. Combined Heart-Lung Transplant in Patients with Eisenmenger's Syndrome in the United States.

BACKGROUND Thoracic transplantation is considered for patients with Eisenmenger's syndrome (ES) who have refractory right ventricular failure despite optimal therapy for pulmonary arterial hypertension. We compared the outcomes of bilateral lung transplant (BLT) with cardiac defect repair versus combined heart-lung transplant (HLT). RESEARCH QUESTION Which is the most effective thoracic transplant strategy in patients with ES? STUDY DESIGN AND METHODS We identified patients with ES who underwent thoracic transplantation from 1987 to 2018 from the UNOS database. Survival curves were estimated using the Kaplan-Meyer method and compared using the log-rank test. RESULTS During the study period, 442 adults with ES underwent thoracic transplantation (316 HLT and 126 BLT). After BLT, overall survival 1, 5 and 10 years posttransplant was 63.1%, 38.5% and 30.2%. After HLT, overall survival 1, 5 and 10 years posttransplant was 68.0%, 47.3% and 30.5% (p=0.6). When survival analysis was stratified by type of defect, patients with an atrial septal defect (ASD) had better survival after BLT than after HLT (88.3% vs 63.2% 1-year-posttransplant, p<0.01; 71.1% vs 49.8% 3-years-posttransplant, p<0.01, 37.4% vs 29.9% 10-years-posttransplant, p=0.08). Patients with a ventricular septal defect (VSD) exhibited better survival after HLT than after BLT (78.2% vs 49.6% 1-year-posttransplant, p<0.01; 55.6% vs 34.3% 5-years-posttransplant, p<0.01; 35.7% vs 26.5% 10-years-posttransplant, p=0.03). The most common cause of mortality in patients with VSD undergoing BLT was cardiac ventricular failure. INTERPRETATION This study suggests that the best transplant option for patients with VSD remains HLT which prevents subsequent development of ventricular failure. BLT with cardiac defect repair should be considered as the first-line treatment option in patients with ES due to an uncorrected ASD. These patients can be considered to have isolated and reversible right ventricular failure akin to patients with advanced pulmonary arterial hypertension.