Chimney stent graft for left subclavian artery preservation during thoracic endograft placement

Abstract

Objective: Carotid to subclavian artery bypass (CSB) has been the standard for revascularizing the left subclavian artery during coverage by thoracic endovascular aortic repair (TEVAR). The purpose of this study is to determine if a chimney stent graft (CSG) offers similar outcomes as an alternative to open bypass.

Methods: A retrospective review of a single vascular surgery registry between February 2011 and September 2017 was performed of all left subclavian revascularization during elective TEVAR. Arch reconstructions involving more than just the left subclavian artery were excluded. Indications, demographics, procedural details, and outcomes were analyzed using standard statistical analysis.

Results: Eighty-one patients with a mean age of 68 years (range, 32-87 years) had left subclavian revascularization (64 [79%] CSB vs 17 [21%] CSG) during TEVAR. Median follow-up for CSG was 8 months (range, 0-52 months) and for CSB was 14.5 months (range, 3-72). Demographics between the groups were similar except for more males in both groups (43 [67%] in CSB vs 10 [59%] in CSG; P = .28). The CSB group had significantly more aneurysms than dissections compared with CSG (45 [70%] vs 6 [35%]; P = .008). There were no perioperative occlusions or ischemic issues for either group in the perioperative period. Postoperative hematoma rates trended higher in the CSB (7.11% vs 1.6%; P = .53) with three (4.6%) of the CSB requiring evacuation of hematoma. Left hemispheric strokes were 6% in the CSB with none occurring in the CSG group. Perioperatively, the CSB group had one recurrent laryngeal nerve and one graft infection. Length of stay was similar in both groups (CSB, 8.4 days vs CSG, 9.1 days). Perioperative mortality was not statistically significant between both groups with two deaths (3%) in the CSB and none in the CSG group. No gutter leaks were identified on follow-up computed tomography scan during long-term follow-up. Patency rates were similar with only one occlusion in the CSB group at 23 months.

Conclusions: Left common carotid to subclavian artery bypass has been the standard for revascularization of the left subclavian artery during coverage by TEVAR. Chimney stent grafting to perfuse the left arm appears to offer equivalent results as a minimally invasive alternative.

Keywords: Left subclavian bypass; Left subclavian revascularization; Subclavian chimney; TEVAR with zone 2 coverage.