Abstract
BACKGROUND: Thoracic endovascular aortic repair (TEVAR) is a minimally invasive technique used to treat type B aortic dissections. Left subclavian artery (LSA) reconstruction is required when treating patients with involvement of LSA. The best antiplatelet therapy after LSA reconstruction is presently uncertain. METHODS: This study retrospectively analyzed 245 type B aortic dissection patients who underwent left subclavian artery revascularization during TEVAR. Out of 245 patients, 159 (64.9%) were in the single antiplatelet therapy (SAPT) group, receiving only aspirin, and 86 (35.1%) were in the dual antiplatelet therapy (DAPT) group, receiving aspirin combined with clopidogrel. During the 6-month follow-up, primary endpoints included hemorrhagic events (general bleeding and hemorrhagic strokes), while secondary endpoints comprised ischemic events (left upper limb ischemia, ischemic stroke, and thrombotic events), as well as death and leakage events. Both univariate and multivariate Cox regression analyses were performed on hemorrhagic and ischemic events, with the Kaplan-Meier method used to generate the survival curve. RESULTS: During the six-month follow-up, the incidence of hemorrhagic events in the DAPT group was higher (8.2% vs. 30.2%, P < 0.001). No significant differences were observed in ischemic events, death, or leakage events among the different antiplatelet treatment schemes. Multivariate Cox regression analysis showed that DAPT (HR: 2.22, 95% CI: 1.07-4.60, P = 0.032) and previous chronic conditions (HR:3.88, 95% CI: 1.24-12.14, P = 0.020) significantly affected the occurrence of hemorrhagic events. Chronic conditions in this study encompassed depression, vitiligo, and cholecystolithiasis. Carotid subclavian bypass (CSB) group (HR:0.29, 95% CI: 0.12-0.68, P = 0.004) and single-branched stent graft (SBSG) group (HR:0.26, 95% CI: 0.13-0.50, P < 0.001) had a lower rate of ischemic events than fenestration TEVAR (F-TEVAR). Survival analysis over 6 months revealed a lower risk of bleeding associated with SAPT during hemorrhagic events (P = 0.043). CONCLUSIONS: In type B aortic dissection patients undergoing LSA blood flow reconstruction after synchronous TEVAR, the bleeding risk significantly decreases with the SAPT regimen, and there is no apparent ischemic compensation within 6 months. Patients with previous chronic conditions have a higher risk of bleeding. The CSB group and SBSG group have less ischemic risk compared to F-TEVAR group.