The aim of the study was to define normal ranges for thoracic aorta and pulmonary artery diameters relative to gender, age, body surface area (BSA) and body mass index (BMI) in healthy Chinese adults by cardiac magnetic resonance (CMR). We studied 200 healthy participants (100 men, 100 women; age range from 20-70) by using a 3.0-T CMR system. The diameters of the ascending aorta (AA), main pulmonary artery (PA), proximal descending aorta (DA) and Valsalva sinus (VAS) were measured manually by two experienced doctors on half-Fourier single-shot spin echo (HASTE) and balanced steady-state free precession (bSSFP) cine images. The mean value and age specific and gender adjusted normal limits were calculated. The linear regression analysis were performed between diameters and gender, age, BMI and BSA. The mean and 95% confidence interval(CI) of AA, PA, DA and VAS were 28.95 ± 4.61 mm(95% CI 19.92-37.99 mm), 22.41 ± 2.59 mm(95% CI 17.31-27.47 mm), 20.61 ± 2.96 mm(95% CI 14.81-26.42 mm), 31.15 ± 3.65 mm(95% CI 24.00-38.29 mm), respectively. The gender differences of all the parameters above were statistically significant (all p < 0.01). Both thoracic aorta and pulmonary artery dilates with the increase of age, while AA has the highest dilation rate. The mean PA/AA was 0.79 and showed no gender difference, but there was statistical difference among all age groups (p < 0.01). AA and DA had stronger association with age and BSA than BMI. Age- and gender-specific reference diameters of thoracic aorta and pulmonary artery were provided in healthy Chinese adults. Age and BSA have stronger effects on the ranges of diameters than BMI.
Keywords: Magnetic resonance imaging; Normal range; Pulmonary artery; Thoracic aorta.