Impact of pre-transplant pulmonary hypertension on survival after heart transplantation: A UNOS registry analysis

Introduction

Severe pre-transplant pulmonary hypertension (PH) has been associated with adverse short-term clinical outcomes after heart transplantation in relatively small single-center studies. The impact of pre-transplant PH on long-term survival after heart transplantation has not been examined in a large, multi-center cohort.

Methods

Adults (≥ 18 years) who underwent first time heart transplantation in the United States between 1987 and 2012 were retrospectively identified from the United Network for Organ Sharing registry. Pre-transplant PH was classified as mild, moderate, or severe based on pulmonary vascular resistance (PVR), trans-pulmonary gradient (TPG), and pulmonary artery (PA) mean pressure. Primary outcome was all-cause mortality.

Results

Data from 26,649 heart transplant recipients (mean age 52 ± 12 years; 76% male; 76% Caucasian) were analyzed. During a mean follow-up of 5.7 ± 4.8 years, there were 10,334 (39%) deaths. Pre-transplant PH (PVR ≥ 2.5 WU) was a significant predictor of mortality (hazard ratio 1.10, 95% confidence interval 1.05–1.14, p < 0.0001) in multivariable analysis. However, the severity of pre-transplant PH (mild/moderate vs. severe) did not affect short or long-term survival. Similarly, even in patients who were supported with either a left ventricular assist device or a total artificial heart prior to transplant, severe pre-transplant PH was not associated with worse survival when compared to patients with mild/moderate pre-transplant PH.

Conclusion

Pre-transplant PH (PVR ≥ 2.5 WU) is associated with a modest increase in mortality when compared to patients without pre-transplant PH. However, the severity of pre-transplant PH, assessed by PVR, TPG, or mean PA pressure, is not a discriminating factor for poor survival in patients listed for heart transplantation.