Donor-recipient predicted heart mass ratio and right ventricular-pulmonary arterial coupling in heart transplant

OBJECTIVES: Right ventricular-pulmonary arterial (RV-PA) coupling interactions are largely unexplored in heart transplant patients. The outcome of this study was RV-PA coupling at 7 and 30 days after heart transplant and its association with donor-recipient size matching. METHODS: Clinical, echocardiographic and haemodynamic data from a retrospective cohort of heart transplant recipients and respective donors were reviewed. Coupling between RV-PA was examined by assessing the RV fractional area change and pulmonary artery systolic pressure ratio. Donor-recipient size matching was assessed by the predicted heart mass (PHM) ratio, and groups with a PHM ratio <1 and >= 1 were compared. RESULTS: Forty-four heart transplant recipients were included in this study (50 years, 57% male sex). Postoperative RV-PA coupling improved from 7 to 30 days (RV fractional area change/pulmonary artery systolic pressure 0.9 +/- 0.3 vs 1.2 +/- 0.3; P < 0.001). A positive association was found between an adequate PHM ratio and improvement of RV fractional area change/pulmonary artery systolic pressure at 30 days, independent of graft ischaemic time and pre-existent pulmonary hypertension (B coefficient 0.54; 95% confidence interval 0.11-0.97; P = 0.016; adjusted R-2 = 0.24). CONCLUSIONS: These findings highlight the role of PHM as a metric to help donor selection and suggest its impact in RV-PA coupling interactions post-heart transplant.