Abstract 9770: Pulmonary Artery Pulsatility Index After Pediatric Heart Transplant

Abstract

Background: The Pulmonary Artery Pulsatility index (PAPi) is calculated by pulmonary artery pulse pressure divided by central venous pressure and is directly proportional to right ventricular contractility and stroke volume, and indirectly proportional to pulmonary artery afterload and filling pressures. We hypothesize that PAPi will correlate with known hemodynamic parameters and predict acute kidney injury (AKI) post heart transplant (HTx). Methods: Medical records and hemodynamic data were retrospectively reviewed for patients ≤18 years old undergoing HTx at a single center between 1/2007-9/2021. Subgroups by HTx indication were myopathy or congenital heart disease (CHD). PAPi was calculated at catheterizations up to 5 years post HTx, with normal ≥ 2.0. Results: Fifty-three children underwent HTx in myopathy (n=27) or CHD (n=26) subgroups. Mean age at HTx was 5.95 ± 6.13 years (range: 58 days-18 years) with no difference between myopathy and CHD subgroups. PAPi correlated with known cardiovascular measures including thermodilution cardiac index (TDCI) and right ventricular end-diastolic pressure (RVEDp), confirming PAPi as a predictor of cardiovascular hemodynamics (Table 1) . At 1 year, children with AKI (n=11/49) had a lower PAPi compared to those with no AKI (1.55 ± 0.43 vs. 2.50 ± 1.16; p=0.004). Comparing initial to 5-year PAPi, the myopathy subgroup (n=18) remained similar (2.10 ± 0.99 vs. 2.12 ± 1.55; p=0.48) and the CHD subgroup (n=12) declined significantly (2.12 ± 0.91 vs. 1.67 ± 0.55; p=0.04). Conclusions: The PAPi in children post HTx correlates with known hemodynamic parameters. PAPi serves as a marker predicting renal dysfunction 1 year post HTx. Between HTx and 5 years post HTx, PAPi did not improve for the myopathy subgroup and declined significantly for the CHD subgroup suggesting that incorporating PAPi into existing risk models may substantially improve earlier implementation for advanced therapies and thus improve clinical outcomes.