Armstrong HF; Schulze PC; Bacchetta M; Thirapatarapong W; Bartels MN.

Respirology. 19(5):675-82, 2014 Jul.
VI 1

BACKGROUND AND OBJECTIVE: Pulmonary hypertension (PH) is a known
complication in patients with interstitial lung disease (ILD).
Cardiopulmonary exercise testing (CPET) is an essential tool for the
assessment of patients with cardiac and pulmonary diseases due to its
prognostic and therapeutic implications. Few studies have evaluated the
relationship between CPET response and mean pulmonary artery pressures
(mPAP) in ILD. The purpose of the present study was to determine and
compare the potential correlations between CPET, 6-min walk test (6MWT),
pulmonary function testing (PFT) and PH in patients with ILD being
evaluated for lung transplantation.

METHODS: The present study reviewed patients with ILD who received lung
transplantations and had CPETs within 2 years before transplantation,
right heart catheterizations, PFTs and 6MWTs within 4 months of CPET.

RESULTS: A total of 72 patients with ILD were analysed; 36% had PH. There
were significant correlations between mPAP and CPET parameters in patients
with PH; but mPAP had no impact on percent of predicted diffusion capacity
of the lung for carbon monoxide or 6-min walk distance (6MWD). CPET
parameters were able to detect differences between levels of severity of
PH through the use of the ratio of minute ventilation to rate of carbon
dioxide production (VE/VCO2) and the partial pressure of end-tidal carbon
dioxide.

CONCLUSIONS: This is the first study that analyses 6MWD, PFT and CPET in
patients with ILD awaiting lung transplantation with and without PH. The
present study demonstrates the significant impact of PH on exercise
capacity and performance in patients with ILD awaiting lung
transplantation.