Interplay of Pulmonary Hypertension and the Effects of Panel-Reactive Antibodies on Outcomes of Heart Transplant Recipients Bridged With Left Ventricular Assist Device

BACKGROUND: Pulmonary hypertension (PH) and sensitization adversely affect heart transplant outcomes. Although left ventricular assist devices may reduce PH, they can increase sensitization. We examined the impact of sensitization on heart transplant outcomes in left ventricular assist device-bridged patients and whether precapillary PH modifies this effect. METHODS: Adults bridged to heart transplant with an left ventricular assist device between 2005 and 2020 were identified from the United Network for Organ Sharing database. Patients with available panel-reactive antibody (PRA) and hemodynamic data were included. Associations between PRA and survival and treated rejection were analyzed. RESULTS: Among 2469 patients, 1053 had precapillary PH (pulmonary vascular resistance [PVR] >2 Wood units [WU]) and 1416 had PVR ≤2 WU. Elevated PRA (>10%) occurred in 566 patients (24.8% with PVR >2 WU; 21.5% with PVR ≤2 WU). Overall, PRA >10% was associated with increased mortality (adjusted hazard ratio [aHR], 1.28 [95% CI, 1.04–1.58], P=0.022), driven by patients with PVR >2 WU (aHR, 1.82 [95% CI, 1.34–2.50], P<0.001), with no association in those with PVR ≤2 WU (aHR, 0.99 [95% CI, 0.47–1.32], P=0.92). PRA >10% was also associated with treated rejection overall (adjusted odds ratio [aOR], 1.41 [95% CI, 1.09–1.82], P=0.008), confined to the PVR >2 WU group (aOR, 1.87 [95% CI, 1.26–2.76], P=0.002) and absent in the PVR ≤2 WU group (aOR, 1.13 [95% CI, 0.80–1.59], P=0.49). CONCLUSIONS: Elevated PRA predicts worse outcomes in LVAD-bridged transplant recepients with precapillary PH, but not in those without precapillary PH.