Midterm Outcomes of Castor Stent Graft in Treatment of Type B Aortic Dissection Involving Left Subclavian Artery: A Retrospective Single‐Center Study

ABSTRACT Objective For type B aortic dissection (TBAD) involving the left subclavian artery (LSA), to secure sufficient proximal landing zones, the LSA can be intentionally covered during thoracic endovascular aortic repair (TEVAR). This study aimed to evaluate the midterm clinical outcomes of endovascular treatment for TBAD involving the LSA using the Castor single‐branched stent graft. Aims The aim of this study was to evaluate the midterm efficacy and safety of Cator stent graft in the treatment of type B aortic dissection involving left subclavian artery. Methods From May 2018 to December 2022, 150 patients with TBAD involving the LSA were treated with the Castor single‐branched stent graft (Micropart Corp, Shanghai, China). The data collected included technical success, incidences of Type I endoleak, retrograde type A dissection (RTAD), stroke, LSA patency, as well as follow‐up mortality and morbidity, and reinterventions. Results The technical success rate was 97.3% (146/150). One patient experienced intraoperative RTAD, two patients had a small type I endoleak, and one patient suffered a stroke. Moreover, one patient developed RTAD on the third day after TEVAR. No in‐hospital aorta‐related mortality, paraplegia, or branch occlusion. During follow‐up, one case (0.7%) of small endoleak, one case (0.7%) of branch occlusion, and two deaths were documented. Complete thrombosis of the false lumens was observed in 140 cases (99.3%). The true lumen diameter at the level of the aortic isthmus and pulmonary artery bifurcation increased significantly (13.3 ± 7.5 vs. 4.2 ± 2.1; 19.8 ± 5.7 vs. 5.4 ± 4.8, p < 0.01), and the ratio of the real lumen increased significantly (0.6 ± 0.2 vs. 0.9 ± 0.1; 0.4 ± 0.1 vs. 0.8 ± 0.1, p < 0.01). The median follow‐up time was 36.0 months (IQR, 11.8 months) (range: 6−72 months). Conclusion The Castor single‐branched stent graft showed favorable midterm outcomes in the treatment of TBAD involving the LSA.