Long-term patency of surgical left subclavian artery revascularization

Abstract

Objective: Little is known regarding the long-term patency rates of surgical left subclavian artery (LSA) revascularization, especially when performed concomitant to thoracic endovascular aortic repair and without arterial occlusive disease. Our aim is to contribute to the existing evidence by reporting the patency rates at mid- and long-term follow-up after surgical LSA revascularization.

Methods: This observational, retrospective, single-center cohort study included 90 eligible patients who underwent a left common carotid artery to LSA bypass (72%) or transposition (28%) from December 31, 2017 to January 1, 2000. Data regarding demographics, medical history, intraoperative characteristics, and outcomes regarding bypass graft or transposition patency, severe stenosis, or occlusion were assessed at discharge, 3 months, 1 year, and maximum follow-up using consecutive follow-up computed tomography scans.

Results: In our predominantly male (74%) cohort with a mean age of 66 years (standard deviation, ±12 years), LSA revascularization was mostly performed concomitant to or adjacent to thoracic endovascular aneurysm repair procedures (98%) with the primary indication for surgery being degenerative or saccular aneurysmatic aortic disease (50%), subacute or acute type B aortic dissection (17%), post-dissection aortic aneurysm (16%), type B intramural hematoma (6%), and other indications (11%). Ninety-seven percent of our left common carotid artery to LSA bypasses were performed using a central, supraclavicular approach, and the other 3% were performed using an infraclavicular approach to the LSA. Median diameter of the bypass was 6 mm (range, 6-12 mm). We found two occlusions at 7.7 and 12.9 months follow-up and four severe stenoses at 21.2, 35.4, 38.3, and 46.7 months follow-up, respectively. Estimated freedom from occlusion was 97% ± 2% and freedom from severe stenosis was 90% ± 4% at both midterm (5 years) and long-term (10 years) follow-up, with a median follow-up duration of 42.2 months for occlusion (25th-75th percentile, 15.4-67.4 months) and 41.9 months (25th-75th percentile, 15.4-67.4 months) for severe stenosis.

Conclusions: Open surgical LSA revascularization may be considered the gold standard to preserve antegrade LSA flow in the context of debranching for thoracic endovascular aneurysm repair or open surgical aortic arch repair, with excellent patency rates at mid-term and long-term follow-up.

Keywords: Bypass; LSA; Left subclavian artery; Patency; Surgical revascularization; Transposition.