Markers identify pulmonary hypertension in combined pulmonary fibrosis, emphysema

Right inferior pulmonary vein diameter and left ventricular short axis diameter at diagnosis are associated with development of pulmonary hypertension development in patients with combined pulmonary fibrosis and emphysema.

“Combined pulmonary fibrosis and emphysema is categorized by upper lobe emphysema and lower lobe fibrosis with relative reservation of lung volumes and severely reduced gas exchange,” Fatima Zeba, MD, family and critical care fellow at Dartmouth-Hitchcock Medical Center and the internal medicine residency program at Kent Hospital at Brown University, said during a presentation at the virtual CHEST Annual Meeting. “Studies on clinical features and outcomes in this condition make the case for approaching it as a disease syndrome that’s distinct from pulmonary fibrosis or emphysema.”

Several markers recently emerged as specific markers for pulmonary hypertension, according to the researchers. The current study investigated the relationship of specific markers to pulmonary hypertension and mortality in patients with combined pulmonary fibrosis and emphysema.

Zeba and colleagues performed a single-center, longitudinal, retrospective cohort study of 82 individuals hospitalized at the Providence VA Medical Center with a discharge diagnosis of pulmonary fibrosis from 2008 to 2018. Patients were divided into those with combined pulmonary fibrosis and emphysema (n = 33) and those with idiopathic pulmonary fibrosis (n = 49).

Pulmonary artery diameter, ascending aorta diameter, right inferior pulmonary vein diameter and left ventricular short axis measurements were made by an experienced thoracic radiologist. Pulmonary hypertension development was defined as an estimated right ventricular systolic pressure of 50 mm Hg or more.

Mean follow-up for the combined pulmonary fibrosis and emphysema group was 44 months and the IPF group was 31 months. Pulmonary artery diameter to ascending aorta diameter ratio greater than 1 was associated with decreased survival in the patients with combined pulmonary fibrosis and emphysema (P = .015). Increased mortality in this population was also associated with the presence of honeycombing (HR = 2.2; 95% CI, 1.31-3.67), traction bronchiectasis (HR = 2.02; 95% CI, 1.15-3.55) and ground glass changes (HR = 0.58; 95% CI, 0.34-0.98) on CT, according to the results.

At diagnosis, right inferior pulmonary vein diameter (correlation coefficient, 6.44; 95% CI, 14.99-17.24) and left ventricular short axis diameter (correlation coefficient, 10.66; 95% CI, 42.24-43.43) were associated with pulmonary hypertension development in patients with combined pulmonary fibrosis and emphysema after correction for age and body surface area, according to the results.

“We believe that the ability to qualify pulmonary hypertension using surrogate markers by noninvasive methods can provide valuable prognostic information to patients with combined pulmonary fibrosis and emphysema,” Zeba said.

Reference:

Zeba F, et al. Chest. 2020;doi:10.1016/j.chest.2020.08.968.