Early Outcomes of Zone 2 Thoracic Endovascular Aortic Repair with an Integrated Branch Stent Graft for the Left Subclavian Artery: Evidence from a Western Centre

Background: Thoracic endovascular aortic repair (TEVAR) is widely used for thoracic aortic diseases, most commonly with a proximal landing in Ishimaru zone 3. When an adequate proximal sealing zone is lacking, extension into zone 2 is required, often necessitating left subclavian artery (LSA) revascularisation. The Castor single branched stent graft provides a fully endovascular solution for zone 2 TEVAR by incorporating an antegrade branch for the LSA. This study reports a single centre Western experience with this device. Method: A retrospective analysis was conducted on 15 consecutive patients undergoing elective zone 2 TEVAR with the Castor single branched stent graft between July 2023 and December 2025. Indications included thoracic aortic aneurysm, subacute or chronic Stanford type B dissection, and penetrating aortic ulcer. The primary endpoint was technical success, defined as accurate deployment without type I or III endoleak and with preserved LSA patency. Secondary endpoints included clinical success, access related complications, intensive care unit (ICU) and hospital stays, re-intervention, and death. Follow up consisted of serial computed tomography angiography. Results: The mean age was 63.9 ± 11 years, and 87% of patients were men. Technical and clinical success were achieved in 14 patients (93%). One patient required adjunctive covered stenting of the LSA for incomplete branch expansion. There were no access related complications or 30 day deaths. Mean ICU and hospital stays were 1.2 ± 0.6 days and 15.3 ± 9.6 days, respectively. Over a mean follow up of 13.5 ± 8.4 months, all LSA branches remained patent, with no endoleak, device migration, or re-intervention. Conclusion: Zone 2 TEVAR using the Castor single branched stent graft appears feasible, safe, and effective in a Western population. In this small elective series, LSA branch patency was maintained and no device related re- intervention occurred during available follow up. Larger studies with longer follow up are needed to assess durability and longer term outcomes.