An arterial ratio can help identify idiopathic pulmonary fibrosis (IPF) patients with a poor prognosis, suggests the findings of registry data from 50 adults.
The ratio of the main pulmonary artery diameter (PA) to the ascending aorta diameter (A) as seen on a chest CT correlates with pulmonary artery pressure,, a pulmonologist in New York, and his colleagues wrote in an abstract from the agenda of the CHEST annual meeting. To determine whether higher PA:A ratios were associated with more biomarker abnormalities, the researchers reviewed 122 CT scans from 50 adults with IPF.
Overall, 48% of the patients had a PA:A ratio of at least 1, according to Dr. Siddiqui and his coauthors. These patients had significantly higher fibrosis scores (P = .0006), GAP index scores (P = .0144), brain natriuretic peptide scores (P = .0046), and pulmonary arterial systolic pressure (P = .0063) compared with patients who had PA:A ratios of less than 1, according to the Kruskal-Wallis test. This test also showed no significant differences on measures of coronary artery calcium, aortic value calcifications, mitral valve calcifications, bronchial wall thickening, emphysema, and spirometry data between the two patient groups, based on PA:A ratios.
Use of the Pearson correlation revealed a positive relationship between PA:A ratios greater than 1 and coronary artery calcium scores, fibrosis scores, and pulmonary arterial systolic pressure, but a negative relationship between a high PA:A ratio and both diffusing capacity and forced vital capacity.
Although the findings were limited by a small study population, the results suggest that clinicians can use the finding of an increased PA:A ratio to help identify IPF patients at greater risk for poor outcomes. Such patients might benefit from pharmacotherapy or transplants, the researchers noted.
Dr. Siddiqui and his coauthors had no financial conflicts to disclose.