Interstitial lung disease-associated pulmonary hypertension - what the future holds

Pulmonary hypertension associated with interstitial lung disease (ILD-PH) is associated with significant alteration of quality of life, exercise capacity, and survival. Over the past 2 years, there were changes in the guideline definition and classification of ILD-PH, and positive randomized controlled trials were published.

Pulmonary hypertension associated with chronic lung disease is now hemodynamically defined as a mean pulmonary artery pressure more than 20 mmHg, with pulmonary artery wedge pressure 15 mmHg or less, and pulmonary vascular resistance (PVR) at least 2 Wood units. Severe ILD-PH is defined by PVR more than 5 Wood units. In the INCREASE trial, patients receiving inhaled treprostinil had favorable significant changes in 6-min walk distance, NT-proBNP level, clinical worsening events, and forced vital capacity, which were maintained in the open label extension study. Promising results were obtained in a placebo-controlled pilot trial using escalated doses of inhaled nitric oxide. According to European guidelines, patients with ILD-PH should be referred to pulmonary hypertension centers, where inhaled treprostinil may be considered; phosphodiesterase type-5 inhibitors may also be considered in patients with severe ILD-PH.

Recent changes in the definitions and a new therapeutic option have an impact on the diagnosis and management of ILD-PH.