Serial Pulmonary Hemodynamics in Patients with Idiopathic Pulmonary Fibrosis Listed for Lung Transplant

Rationale: Pulmonary hypertension (PH) commonly complicates idiopathic pulmonary fibrosis (IPF). However, the rate of change in pulmonary hemodynamics in IPF remains poorly defined. Objectives: To examine the rate of change in pulmonary hemodynamics among patients with IPF. Methods: The rate of change in mean pulmonary artery pressure (mPAP) and pulmonary vascular resistance (PVR) was examined in patients with IPF listed for lung transplantation. The fifth and seventh World Symposium on Pulmonary Hypertension definitions for precapillary PH were used in this analysis. Measurements and Main Results: There were 496 patients with IPF who had at least two right heart catheterizations (RHCs) while listed for lung transplantation. The median time between repeated RHCs was 9 months (interquartile range [IQR], 6 to 14 mo). PH was present in 25.8% and 46.8% at the first RHC, whereas 42.9% and 64.3% had PH by the two definitions, respectively, at the time of the final RHC. The median rate of change in the mPAP and PVR were 3.8 mm Hg/yr (IQR, 20.9 to 11.8) and 0.8 Wood units/yr (IQR, 20.2 to 2.4), respectively. The rate of PVR change was slower for those with established PH than those without PH. A total of 28.6% of the patients had accelerated progression of their hemodynamics, arbitrarily defined as an increase in PVR of >2 Wood units/yr. Conclusions: PH associated with IPF tends to progress in an unpredictable fashion, with some patients demonstrating an accelerated phenotype. Among patients with RHC hemodynamics below the threshold for therapy, close vigilance is warranted, with consideration for an early repeat RHC.