Accuracy of CT Pulmonary Artery Diameter for Pulmonary Hypertension in End-Stage COPD

Pulmonary hypertension (PH) in COPD is associated with a higher mortality and an increased risk on exacerbations compared to COPD patients without PH. The aim was to evaluate the diagnostic value of pulmonary artery (PA) measurements on chest computed tomography (CT) for PH in end-stage COPD.

COPD patients evaluated for eligibility for lung transplantation between 2004 and 2015 were retrospectively analyzed. Clinical characteristics, chest CTs, spirometry, and right-sided heart catheterizations (RHC) were studied. Diameters of PA and ascending aorta (A) were measured on CT. Diagnostic properties of different cut-offs of PA diameter and PA:A ratio in diagnosing PH were calculated.

Of 92 included COPD patients, 30 (32.6 %) had PH at RHC (meanPAP > 25 mm Hg). PA:A > 1 had a negative predictive value (NPV) of 77.9 % and a positive predictive value (PPV) of 63.1 % with an odds ratio (OR (CI 95 %)) of 5.60 (2.00-15.63). PA diameter ≥30 mm had a NPV of 78 % and PPV of 64 % with an OR (CI 95 %) of 6.95 (2.51-19.24).

A small PA diameter and PA:A make the presence of PH unlikely but cannot exclude its presence in end-stage COPD. A large PA diameter and PA:A maybe used to detect PH early.