Age-related differences in acute aortic dissection.

Objective: The present study investigated the differences in clinical characteristics, treatments, and outcomes of patients with acute aortic dissection (AAD) in different age groups.

Methods: The present single-center retrospective study was conducted from August 2014 to August 2020. The patients were divided into three groups: age <45 years (young group), age 45 to 59 years (middle-age group), and age >59 years (elderly group). Type A (TAAD) and type B (TBAD) aortic dissection were evaluated separately using the latest definitions.

Results: The mean age at onset was 52.4 years in our cohort of 602 patients. The young group included a large proportion of male patients (86%). The body mass index and body surface area were higher in the young group. The proportion of non-true lumen blood supply of branches on the abdominal aorta in the young group (27%-55%) was greater than that in the others. In the young group, the distal extent of dissection in 84% of TAAD and 89% of TBAD exceeded the abdominal aortic branch cluster (AABC) compared with 36% of TAAD and 58% of TBAD in the elderly group. The multivariate analysis revealed that age <45 years (odds ratio, 5.15; P < .001) and D-dimer level (odds ratio, 1.05; P = .001) were risk factors for intimal flap tear exceeding the AABC. The proportion of visceral and lower limb malperfusion increased from 4.8% to 36.9% as the intimal flap tear exceeded the AABC.

Conclusions: Compared with middle-age and elderly patients, young patients with AAD had two characteristics (ie, obesity and an intimal flap that had frequently exceeded the branches of the aorta). These two factors resulted in a greater proportion of non-true lumen blood supply, increased visceral and lower limb malperfusion, and an increase in potential associated risks.