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

Abstract

IntroductionPulmonary 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.MethodsCOPD 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.ResultsOf 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).ConclusionA 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.

CT-Derived Pulmonary Artery Diameters to Preselect for Echocardiography in COPD Patients Eligible for Bronchoscopic Treatments

“…In patients with severe COPD, an mPA diameter ≥30 mm has been associated with PH [11]. In our study, all 3 patients with an RVSP >50 mm Hg had mPA and pPA diameters ≥30 mm.…”

“…Since only 3 patients in our cohort had an RVSP >50 mm Hg, the sample size was too small to calculate sensitivity and specificity for the different PA diameters. Therefore, we used the threshold of a PA diameter ≥30 mm based on an earlier study [11]. In this study, a PA diameter ≥30 mm was shown to have the highest positive and negative predictive value in the detection of PH in patients with severe COPD.…”

“…This prompted the evaluation of noninvasive alternatives for echocardiography in the screening of patients for PH. Computed tomography (CT)-derived pulmonary artery (PA) diameter measurements and a pulmonary artery to aorta (PA:A) ratio >1 have been proposed as alternative screening tools for PH, but studies in patients with severe COPD are scarce [10, 11].…”

Screening For Pulmonary Hypertension With Multidetector Computed Tomography Among Patients With Severe Aortic Stenosis Undergoing Transcatheter Aortic Valve Implantation

“…Similary, Sanal et al observed in a retrospective study among patients with pulmonary embolism (mean age 59 ± 15 years) that a PA/AA ratio ≥ 1.0 had a 59% sensitivity, 82% specificity, a 55% positive predictive value, and a 84% negative predictive value for diagnosing moderate to severe PH defined as a pulmonary artery systolic pressure ≥ 50 mmHg on Doppler Echo ( 13 ). Mohamed Hoesein et al ( 14 ) assessed the accuracy of CT PA diameter and PA/AA ratio for PH in end-stage COPD among 92 patients (mean age 55 years) and found that a PA/AAratio >1 had a negative predictive value of 77.9% and a positive predictive value of 63.1%. However, the results of the present study would suggest that in an elderly patient population, such as those selected to undergo TAVI, a PA/AA ratio ≥ 1.0 would not be sensitive enough as we observed a sensitivity of just 4.4% when PA/AA ratio ≥ 1.0 was used to predict the presence of PH.…”

<p>Assessing pulmonary hypertension in COPD. Is there a role for computed tomography?</p>

“…Usually, MAP widest dimension is measured on axial CT images, on inspiratory acquisition, at bifurcation level, and, AO is measured on the same image 107,108,111,112. Descending aorta is also measured at the same level.112 Thresholds values to detect PH in COPD patients are: MAP ≥29 mm21,113,114 and MAP/AO>1 107,110,111,115,116Figure 3Pulmonary artery and aorta measurements.…”