Pre-transplant reversible pulmonary hypertension predicts higher risk for mortality after cardiac transplantation

Abstract

Background Pre-transplant fixed pulmonary hypertension is associated with higher post-transplant mortality. In this study, we assessed the significance of pre-transplant reversible pulmonary hypertension in patients undergoing cardiac transplantation. Methods Overall, we studied 182 patients with baseline normal pulmonary pressures or reversible pulmonary hypertension, defined as a decrease in pulmonary vascular resistance (PVR) to ≤2.5 Wood units (WU), who underwent cardiac transplantation. Multiple recipient and donor characteristics were assessed to identify independent predictors of mortality. Results The average duration of follow-up was 42 ± 28 months. Forty patients (22%) died during the follow-up period. Baseline hemodynamics for alive vs dead patients were as follows: pulmonary artery systolic (PAS) 42 ± 15 vs 52 ± 15 mm Hg; PA diastolic 21 ± 9 vs 25 ± 9 mm Hg; PA mean 28 ± 11 vs 35 ± 10 mm Hg; transpulmonary gradient (TPG) 9 ± 4 vs 11 ± 7 mm Hg (all p < 0.05); total pulmonary resistance 7.7 ± 4.8 vs 8.8 ± 3.2 WU ( p = 0.08); and PVR 2.3 ± 1.5 vs 2.9 ± 1.6 WU ( p = 0.06). In an unadjusted analysis, patients with PAS >50 mm Hg had a higher risk of death (odds ratio [OR] 5.96, 95% confidence interval [CI] 1.46 to 19.84 as compared with PAS ≤30 mm Hg). There was no significant difference in survival among patients with baseline PVR <2.5, 2.5 to 4.0 or >4.0 WU, but patients with TPG ≥16 had a higher risk of mortality (OR 4.93, 95% CI 1.84 to 13.17). PAS pressure was an independent predictor of mortality (OR 1.04, 95% CI 1.02 to 1.06). Recipient body mass index, history of sternotomy; and donor ischemic time were the other independent predictors of mortality. Conclusion Pre-transplant pulmonary hypertension, even when reversible to a PVR of ≤2.5 WU, is associated with a higher mortality post-transplant.