Determining the normal range of mediastinal vascular structures and heart chambers is important for accurate evaluation and diagnosis of cardiopulmonary diseases. The aim of this work was to determine the average sizes of heart chambers, mediastinal vascular structures, and the ratio of the main pulmonary artery-to-ascending aorta (MPA-to-AA) in children without congenital or acquired cardiopulmonary diseases on contrast-enhanced (CE) chest multidetector computed tomography (MDCT). In total, 356 participants (range 0-216 months) were enrolled. The interobserver correlation (ICC) analysis performed and P-value is considered significant if <0.05. The mean diameters for the left and right ventricle and atrium, ascending aorta, descending aorta at the level of the mediastinum, descending aorta at the level of the diaphragm, main pulmonary artery, right pulmonary artery, and MPA-to-AA ratio were revealed for 6 age groups. Mediastinal vascular structures have excellent and heart chambers have a substantial-to-excellent ICC agreement. The diameters of heart chambers and mediastinal vascular structures on CE-chest MDCT are easy to measure and might be used as a reference to refer patients for further investigations.
