Clinical assessment for pulmonary hypertension in interstitial lung disease

Abstract

Background: Pulmonary hypertension (PH) is an important complication of interstitial lung disease (ILD), as its development confers a poor prognosis. There are no specific recommendations for methods of assessment for PH in ILD populations.

Aims: To determine current assessment practices for PH in an Australian ILD centre.

Methods: In the Austin Health ILD database, 162 consecutive patients with idiopathic pulmonary fibrosis or connective tissue disease-associated ILD were identified and retrospectively evaluated for methods of PH assessment with transthoracic echocardiography (TTE), serum N-terminal pro-brain natriuretic peptide (NT-proBNP) and right heart catheterisation (RHC) in relation to patient demographic and physiological parameters.

Results: The median follow-up was 30 (14.4-56.4) months. At baseline, vital capacity was 80.0 ± 18.4% predicted, and diffusing capacity for carbon monoxide was 59.6 ± 15.2% predicted. Evaluation for PH was performed in 147 (90.7%) patients, among whom 105 (64.8%) had TTE performed at least once. At the initial TTE, 33.7% patients had high probability of PH, defined as RVSP >40 mmHg + RAp and/or right ventricular dysfunction. At the time of the most recent TTE, these criteria were met in 45 (52.3%) patients. Elevated serum NT-proBNP levels during the first year were observed in 47 (38.8%) patients. Only 14 (8.6%) patients had RHC.

Conclusion: Our institutional PH assessment practice in ILD demonstrates a substantial prevalence of probable PH at baseline. As new therapies emerge for the treatment of PH in ILD, well-defined screening practices are important in this population for early identification and optimal management.

Keywords: connective tissue disease; idiopathic pulmonary fibrosis; interstitial lung disease; pulmonary hypertension; screening.