Lung transplant bridging strategies in patients with idiopathic pulmonary fibrosis: An SRTR database analysis

Extracorporeal Membrane Oxygenation (ECMO) plays an important role in bridge-to-transplant, but the ideal bridging strategy is not well-defined for idiopathic pulmonary fibrosis (IPF), particularly in the setting of pulmonary hypertension (PH).

We queried data from the Scientific Registry of Transplant Recipients database for adult lung transplant candidates with IPF who were bridged to lung transplant, either with venovenous (VV)-ECMO, venoarterial (VA)-ECMO, or mechanical ventilator (MV) alone. A subgroup analysis was performed on patients with moderate-severe PH (mean pulmonary artery pressure ≥ 40 mmHg).

During the period, 1485 patients were identified who met inclusion criteria: 653 on VV-ECMO, 234 on VA-ECMO, and 598 on MV. The competing risk analysis found that relative to VV-ECMO, both VA-ECMO and MV bridge were associated with lower rates of survival to transplant (HR 0.69 [0.57-0.84], p < 0.001; HR 0.39 [0.383-0.46], p < 0.001, respectively). Within the PH subgroup, there was no difference in survival to transplant between VV- and VA-ECMO (HR 1.01 [0.64-1.58]; p > 0.9), but patients bridged with ventilator had a lower waitlist survival rate HR 0.46 [0.27, 0.79]; p = 0.005) relative to VV-ECMO. There was no difference in long-term survival among the three bridging strategies, either in the complete cohort (p = 0.52) or the PH cohort (p = 0.84).

Even in the presence of severe PH, VA- and VV-ECMO were both effective in bridging IPF patients to lung transplant, and VV-ECMO can be an initial setup for bridging. Conversion to VA ECMO may be considered early when there is a sign of right ventricular dysfunction.