The Long-Term Fate of Aortic Branches in Patients with Aortic Dissection

OBJECTIVE: Late morbidity and mortality related to aortic branches in patients with aortic dissection (AD) are not well described. We aimed to investigate the fate of aortic branches in a population cohort of patients with newly diagnosed AD.METHODS: We used the Rochester Epidemiology Project record linkage system to identify all Olmsted County, MN, residents diagnosed with AD from 1995 to 2015. Only patients with >30 days of available follow-up imaging were included in the analysis. The primary outcome was freedom from any branch-related event (any intervention, aneurysm, malperfusion, rupture, or death occurring after the acute phase >14 days). Secondary outcome was the diameter change of the aortic branches. Univariate and multivariable Cox proportional hazards models were used to identify predictors of branch-related events; univariate and multivariate linear regression models were used to assess aortic branches growth rate.RESULTS: Of 77 total incident AD cases, 58 patients who survived with imaging follow-up were included, 28 (48%) with type A and 30 (52%) with type B AD. The presentation was acute in 39 (67%) cases; 6 (10%) had branch malperfusion. Of 177 aortic branches involved by the AD, 81 (46%) arose from the true lumen, 33 (19%) from the false lumen, 63 (36%) from both. After the acute phase, freedom from any branch-related event at 15 years was 48% (95%CI 32-70). Thirty-one branch-related events occurred in 19 patients over 15 years: 12 interventions (76% freedom, 95%CI 63-92), 10 aneurysms (67% freedom, 95%CI 50-90), 8 malperfusions (76% freedom, 95%CI 61-94) and 1 rupture (94% freedom, 95%CI 84-100). There were no branch-related deaths. Type B AD (HR 3.5, 95%CI 1.1-10.8; P=.033), patency of the aortic false lumen (HR 6.8, 95% CI 1.1-42.2; P=.038) and malperfusion syndrome at presentation (HR 6.0, 95% CI 1.3-28.6; P=.023) were predictors of late aortic branches-related events. Overall growth rate of aortic branches was 1.3±3.0 mm/year. Patency of the aortic false lumen, initial branch diameter, and Marfan syndrome were significantly associated with diameter increase.CONCLUSIONS: In patients with AD, aortic branch involvement was responsible for a significant long-term morbidity, without any related mortality. Type B AD, patency of the aortic false lumen, or malperfusion syndrome at presentation had a higher risk of branch events during the long-term follow-up. Dilatation of the aortic branches was observed in one third of cases during follow-up, in particular in case of a patent aortic false lumen or Marfan syndrome.