Hemodynamic assessment of inhalational epoprostenol for post-operative right ventricular dysfunction in cardiac surgery patients

ABSTRACT

Introduction: Right ventricular (RV) dysfunction after cardiac surgery presents a significant challenge. Epoprostenol (EPO) is a pulmonary vasodilator that can be administered via inhalation and is often used in patients with post-operative RV dysfunction. However, the effects of EPO on RV performance have not been well studied. Furthermore, EPO is generally contraindicated in WHO Group 2 pulmonary hypertension. The purpose of this study is to describe the hemodynamic consequences of weaning inhaled epoprostenol (iEPO) in post-operative RV dysfunction and potentially identify any predictive markers for successful weaning. Methods: This is a single-center case series of patients receiving iEPO after cardiac surgery identified by convenience sampling. Inclusion criteria included post-cardiac surgery patients, >18 years, and receiving iEPO for RV dysfunction. Exclusion criteria included pregnancy, open chest, SARS-COV-2 pneumonia, left ventricular assist device use, extracorporeal membrane oxygenation use, heart transplantation, or receiving iEPO for refractory hypoxia. A paired two sample t-test compared the hemodynamic parameters collected pre and post iEPO weaning. Results: EPO weaning was associated with a decrease in mean pulmonary artery pulsatility index (PAPi) (pre-wean 1.81 vs post-wean 1.57, p=0.04) and increase in pulmonary artery systolic pressure (PASP) (46.5mmHg vs 55.1mmHg, p=0.01). Cardiac index and right atrial pressure were not significantly different (p=0.35 and p=0.26 respectively). Case 5 had EPO weaning failure and had the lowest baseline PAPi in the cohort. Conclusion: iEPO weaning is associated with dynamic changes in PASP and PAPI in post-operative cardiac surgery patients. This finding supports the conceptual role of iEPO in improving post-operative RV-PA coupling and RV performance. Baseline PAPi may be a predictive marker to guide the weaning process. However, larger cohorts are needed to confirm these findings.