Effects of Pulmonary Hypertension on Kidney Function

There is a scarcity of data defining hemodynamic correlates of renal function in pulmonary hypertension (PH). The aim of this study was to assess the correlation between standard and novel hemodynamic indices, including the pulmonary artery pulsatility index (PAPi) and the right atrial to pulmonary capillary wedge pressure (RA:PCWP) ratio, and renal function in PH. We conducted a retrospective study of adult patients with PH diagnosed by right-heart catheterization (RHC) between January 2007 and October 2012 at Einstein Medical Center, Philadelphia. Patients with end-stage renal disease were excluded. Pulmonary artery pulse pressure, RA:PCWP, PAPi (pulmonary artery pulse pressure/RA), as well as standard RHC variables were studied. The final cohort consisted of 171 patients. The median age was 59±13 years, 52% were men, and the mean pulmonary arterial pressure was 39±8.9 mm Hg. Sixty-eight patients had worsening creatinine from the time of admission to the time of RHC. Patients with a RA:PCWP of >0.86 had a significantly higher creatinine level at RHC (2.2±1.0 vs. 1.7±1.7 mg/dL, P=0.01) and worsening creatinine (+0.9±0.9 vs. +0.4±0.3 mg/dL, P=0.03). The major finding of this study is that in PH (all groups), worsening renal function from the time of admission to RHC correlated significantly with high RA:PCWP and low ejection fraction. High RA:PCWP was found to be a better predictor of worsening renal function than other novel and standard hemodynamic indices such as elevated right atrial pressure and PAPi.