Risk factors for distal stent graft-induced new entry after endovascular repair in uncomplicated type B aortic dissection.

OBJECTIVE:We investigated the risk factors for distal stent graft-induced new entry (dSINE) after thoracic endovascular aortic repair for patients with uncomplicated type B aortic dissection (TBAD) and reported the outcomes of using a tapered stent graft and dSINE reintervention. METHODS:A total of 226 patients with uncomplicated TBAD who had undergone thoracic endovascular aortic repair between January 2010 and December 2018 were analyzed retrospectively. The global features of the thoracic aorta and the local features of the proximal and distal landing zones were evaluated and compared between the dSINE and non-dSINE groups. A multivariate Cox model was used to identify the independent risk factors for dSINE. The cumulative incidence of reintervention was estimated using competing risk models. RESULTS:After a median follow-up of 4.6 years, 16 patients (7.1%) had developed dSINE. Multivariable Cox regression analysis demonstrated that a type III aortic arch, decreased angle, increased distal oversizing, and increased distal mismatch ratio were significant risk factors for dSINE. Of the patients with tapered stent grafts, five with a ≤4-mm taper had developed dSINE. However, no dSINE was seen in the >4-mm taper group (P = .024). Reintervention was performed for 7 of the 16 patients with dSINE (43.8%). The mean time from the initial detection of dSINE to reintervention was 6.43 ± 4.62 months. The competing risk analyses showed that the cumulative incidence of reintervention in the dSINE group at 1, 3, and 5 years was 25.0%, 37.5%, and 43.5%, respectively. CONCLUSIONS:A type III aortic arch, excessive distal oversizing and mismatch ratio, and severe angulation were associated with dSINE in patients with uncomplicated TBAD. The use of a tapered stent graft with a >4-mm taper could help prevent dSINE in patients with a high taper ratio. Aggressive reintervention was associated with favorable long-term outcomes for patients with progressive dSINE.