Morphological features of the thoracic aorta and supra-aortic branches in patients with acute Type A aortic dissection in China

Abstract

OBJECTIVES This study aimed to investigate the morphological characteristics of the dissected thoracic aorta and brachiocephalic arteries within the Chinese population. METHODS A retrospective analysis of computed tomography scans of 387 patients with acute Type A aortic dissection was carried out. The dimensions of the thoracic aorta at multiple levels and other imaging characteristics were studied. RESULTS The patients with a maximum diameter ≥55 mm accounted for less than one-third of the population. Among those without Marfan syndrome (MFS) (n = 349), only 114 (32.8%) patients had a maximal aortic diameter ≥ 55 mm, whereas among those with MFS (n = 38), 20 (78.9%) had a maximal aortic diameter ≥ 45 mm. The predicted maximum aortic diameter is 88.46 - 0.81 × height (cm) + 63.02 × body surface area (m 2) + 5.50 × (if diabetes, 1, if not, 0) - 6.63 × (if hypertension, 1, if not, 0). A positive correlation was established between a circular false lumen and the probability that brachiocephalic arteries were involved by dissection. The size ratio of false lumen to true lumen was greater in the circumferential group when compared with the crescent group. The independent predictors for the circumferential false lumen were age, atherosclerosis and smoking. CONCLUSIONS Herein, the morphological characteristics of the thoracic aorta among Chinese patients with acute Type A aortic dissection were described. The currently recommended criteria for prophylactic aorta surgery were applied to most patients with MFS but not to those without MFS within the Chinese population. Furthermore, the shape of the false lumen was identified as a putative risk factor that might affect the prognosis of the patients.