Anatomical feasibility of a ‘semi-custom’ unibody single-branch endograft in previous zone 2 thoracic endovascular aortic repair

OBJECTIVES: The aim of this study was to evaluate the suitability of a subclavian unibody single-branch endograft among patients treated with thoracic endovascular aortic repair (TEVAR) in landing zone 2 (LZ2). METHODS: This is a pre-clinical, single-centre, real-world, all-comers, retrospective cohort study. Patients treated with TEVAR in LZ2 with an available preoperative computed tomography angiography were included. The primary outcome was the anatomical feasibility of the Castor endograft in patients receiving endovascular treatment in LZ2 between 1999 and 2022. Secondary outcomes were: a comparison of feasible and unfeasible patients; frequencies and description of exclusion causes; non-feasibility risk factor analysis; and analysis of the stent graft configurations necessary to treat 75% of the patients. A logistic regression model was used to find associations between baseline morphological data and non-feasibility. RESULTS: A total of 473 procedures were performed and 72 patients fulfilling inclusion criteria were included. The mean distance between the left carotid artery and left subclavian artery (or between innominate artery and bovine trunk) was 12.4 ± 5.2 mm and its average diameter was 33.0 ± 10.6 mm. The pre-vertebral left subclavian artery’s diameter and length were 11.3 ± 2.5 and 38.7 ± 10.8 mm. Forty-nine (68.1%) patients were suitable for Castor implantation. Twenty-one configurations were required to treat 75% of feasible patients and might be lowered to 12 configurations applying less strict criteria. CONCLUSIONS: The Castor endograft was anatomically feasible in several patients requiring TEVAR in LZ2. Three-quarters of feasible patients could be treated with a reasonable number of configurations, paving the path for future off-the-shelf applications.