Donor-Recipient Predicted Heart Mass Ratio as Predictor of Right Ventricular-Pulmonary Arterial Coupling Post Heart Transplantation

Abstract

Background Right ventricular dysfunction is a frequent complication after heart transplantation. Right ventricular-pulmonary arterial (RV-PA) coupling interactions negatively impact right ventricular function and have prognostic implications in heart failure; yet, the temporal profile of RV-PA interactions in the context of heart transplantation has not been explored, particularly its relationship with donor-recipient size matching. Our aim was to assess RV-PA coupling at seven and 30 days after heart transplantation and to study its association with donor-recipient size matching. Methods Clinical, echocardiographic and hemodynamic data from a retrospective cohort of consecutive adult heart transplant recipients and their respective donors were reviewed. Coupling between RV-PA was examined by the ratio between right ventricular fractional area change and pulmonary artery systolic pressure (RVFAC/PASP) at seven and 30 days post-transplant. Donor-recipient size matching was assessed by donor-recipient predicted heart mass (PHM) ratio, and appropriate size graft was defined as PHM ratio ≥1. Predictors of RV-PA coupling were examined by multiple linear regression analysis. Results Thirty-four patients transplanted between July/2015 and June/2018 were included (48 ± 15 years, 50% male). Fifty percent had pre-transplant pulmonary hypertension (mean pulmonary artery pressure 25.71 ± 7.12 mmHg). Median PHM ratio was 1.08 (p25-75: 0.94-1.29), and 40% grafts were considered undersized. Post-transplant RV-PA coupling was decreased and improved from seven to 30 days (RVFAC/PASP 0.98 ± 0.24 vs. 1.26 ± 0.27; p Conclusions These findings suggest the impact of PHM on RV-PA coupling interactions and, subsequently, in right ventricular dysfunction post heart transplantation. This highlights the role of PHM ratio as a metric to improve donor selection.