Abstract Introduction Veno-venous extracorporeal membrane oxygenation (V-V ECMO) is increasingly used to bridge patients to lung transplantation (BTT). The development of right ventricular (RV) failure on V-V ECMO is associated with poor clinical outcomes. If recognized early, patients who are transitioned to an alternate configuration such as veno-arterial (V-A) or veno-arterio-venous (V-AV ECMO) can have improved outcomes. Elevated pre-transplant baseline mean pulmonary artery pressure (mPAP) predicts the need for intraoperative RV support with ECMO, however, this has not been previously shown in BTT cohorts. We hypothesized that patients who required configuration change would have elevated measures of RV afterload and RV work on their pre-transplant right heart catheterization (RHC). Methods A retrospective cohort of patients initiated on V-V ECMO as BTT from 2020-2024 with RHC within 1 year prior to cannulation was identified. Baseline characteristics were collected. Subjects were stratified by need for ECMO configuration change for RV support. Measures of RV afterload and function were obtained, including mPAP, Pulmonary Arterial Compliance (PAC) systolic pulmonary artery pressure (sPAP)-diastolic pulmonary artery pressures(dPAP)/stroke volume, pulmonary arterial pulsatility index (PAPi) sPAP-dPAP/Right atrial pressure (RAP), and RV stroke work index stroke index x (mPAP-RAP) x 0.0136. Variables were compared between groups using the Mann-Whitney U test. Results 6 (17%) patients required configuration change and 29 (83%) did not. 34/35 (97%) had a primary diagnosis of interstitial lung disease. There were no significant differences in median age, duration of ECMO, pre-ECMO percent predicted forced vital capacity (%FVC), PaO2/FiO2, or PaCO2 at time of cannulation. In patients requiring V-A/V-AV ECMO there were no differences in PAPi, however, mPAP and RVSWI were significantly higher, and the PA compliance significantly lower. Conclusions Patients who developed significant RV failure requiring conversion from V-V ECMO to V-A/V-AV were similar in terms of degree of respiratory impairment both at baseline and at the time of cannulation to those maintained on V-V ECMO. Our data suggests that patients who require configuration change face elevated baseline load as noted by higher RVSWI and mPAP as well as increased stiffness of the pulmonary circulation due to decreased compliance, placing them closer to the point of RV-pulmonary artery uncoupling and RV failure prior to ECMO initiation. Further analysis is required to determine optimal cutoffs for these values. This abstract is funded by: None
Kurtzman et al. (Fri,) studied this question.