Pulmonary arterial hypertension in children: diagnosis using ratio of main pulmonary artery to ascending aorta diameter as determined by multi-detector computed tomography

• Published in: Pediatric radiology Vol. 46; no. 10; pp. 1378 - 1383
• Main Authors: Caro-Domínguez, Pablo, Compton, Gregory, Humpl, Tilman, Manson, David E.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-09-2016; Springer Nature B.V
• Subjects: Adolescent; Aorta - diagnostic imaging; Cardiac Catheterization; Child; Child, Preschool; Female; Humans; Hypertension, Pulmonary - diagnostic imaging; Imaging; Infant; Infant, Newborn; Male; Medicine; Medicine & Public Health; Neuroradiology; Nuclear Medicine; Oncology; Original Article; Pediatrics; Predictive Value of Tests; Pulmonary Artery - diagnostic imaging; Radiology; Tomography, X-Ray Computed - methods; Ultrasound; Ascending aorta; Main pulmonary artery; Pulmonary arterial hypertension; Ratio; Children; Computed tomography
• ISSN: 0301-0449; 1432-1998
• DOI: 10.1007/s00247-016-3636-5

Background
The ratio of the transverse diameter of the main pulmonary artery (MPA) to ascending aorta as determined at multi-detector CT is a tool that can be used to assess the pulmonary arterial size in cases of pulmonary arterial hypertension in children.
Objective
To establish a ratio of MPA to ascending aorta diameter using multi-detector CT imaging suggestive of pulmonary arterial hypertension in children. We hypothesize that a defined ratio of MPA to ascending aorta is identifiable on multi-detector CT and that higher ratios can be used to reliably diagnose the presence of pulmonary arterial hypertension in children.
Materials and methods
We calculated the multi-detector CT ratio of MPA to ascending aorta diameter in 44 children with documented pulmonary arterial hypertension by right heart catheterization and in 44 age- and gender-matched control children with no predisposing factors for pulmonary arterial hypertension. We compared this multi-detector-CT-determined ratio with the MPA pressure in the study group, as well as with the ratio of MPA to ascending aorta in the control group. A threshold ratio value was calculated to accurately identify children with pulmonary arterial hypertension.
Results
Children with documented primary pulmonary arterial hypertension have a significantly higher ratio of MPA to ascending aorta (1.46) than children without pulmonary arterial hypertension (1.11). A ratio of 1.3 carries a positive likelihood of 34 and a positive predictive value of 97% for the diagnosis of pulmonary arterial hypertension.
Conclusion
The pulmonary arteries were larger in children with pulmonary arterial hypertension than in a control group of normal children. A CT-measured ratio of MPA to ascending aorta of 1.3 should raise the suspicion of pulmonary arterial hypertension in children.