Castor stent reconstruction of left subclavian artery reduces the incidence of postoperative cerebral infarction of type B aortic dissection with insufficient proximal landing area: a propensity score matched analysis.

Background: Compared with conventional treatment of type B aortic dissection (TBAD) with insufficient proximal anchoring by covering the left subclavian artery (LSA), reconstructing LSA with Castor branch stent is a promising strategy. Prior studies lacked comparisons with partial LSA coverage, so we used propensity score matching analysis (PSMA) to retrospectively evaluate both approaches. Methods and results: We studied 377 patients with thoracic aortic dissection (TBAD) who underwent thoracic endovascular aortic repair (TEVAR) at one center. Of these, 262 had partial LSA coverage, and 115 had LSA reconstruction with a Castor stent. Using PSMA, we created 92 matched pairs for analysis. Kaplan-Meier and Cox regression analyses were conducted to assess the primary outcome of any postoperative cerebral infarction, encompassing both symptomatic strokes and silent brain infarcts, with each component also evaluated as secondary outcomes. Symptomatic strokes were confirmed by neurological symptoms combined with magnetic resonance imaging (MRI) or computed tomography (CT) scans, while silent brain infarcts were detected through routine postoperative CT/MRI scans for all patients, and both outcomes were included in the primary composite outcome of postoperative cerebral infarction. Additionally, all-cause mortality and postoperative LSA occlusion were examined. The Castor group showed less renal insufficiency (18.7% vs. 38.3%, Conclusions: In TBAD with insufficient proximal anchoring, Castor branch stent reconstruction reduces cerebral infarction over a median follow-up of 26 (IQR 16-38) months (433.8 total person-years), compared to partial LSA coverage.