Hybrid Revascularization of Chronic Vertebral Artery Occlusion: A Morphology-Based Classification, Novel Collateral-Channel Techniques, and Mid-Term Patency in a Single-Center Series of 26 Procedures

Background Chronic vertebral artery (VA) occlusion encompasses heterogeneous morphologies-de novo atherosclerotic occlusion, in-stent restenosis (ISR), and in-stent occlusion (ISO)-for which no classification-guided revascularization strategy exists. We report the largest single-center series of hybrid revascularization combining VA endarterectomy (VEA) with endovascular techniques, propose a morphology-based classification, and provide the first mid-term patency analysis. Methods Twenty-six consecutive hybrid revascularization procedures performed in 25 patients with chronic VA occlusion between January 2018 and March 2026 were retrospectively analyzed. Lesions were classified as Type I (de novo occlusion), Type II (post-stent ISR), or Type III (post-stent ISO), with a complexity modifier "C" denoting long-segment extension, tortuous/deep origin, or absence of a distal target. Technical success, periprocedural complications, and patency at last imaging follow-up were assessed. Results Technical success was 88.5% (23/26) overall, declining across morphological types: 100% in Type I, 88.9% in Type II, and 71.4% in Type III. The C modifier strongly predicted failure (success 50.0% vs. 100% without C; P = 0.008). There was no periprocedural stroke or death; one major cardiac event (3.8%) occurred. At last follow-up (median 34 months; range, 3-96 months), 19 of 23 successfully recanalized arteries (82.6%) remained patent. Mid-term patency was 100% with adjunctive stenting versus 63.6% without (P = 0.037); both reocclusions and one of two restenoses followed stent explantation without re-scaffolding. Novel bailout techniques-VA transposition to the thyrocervical trunk and retrograde revascularization through the ascending cervical artery collateral-rescued three complex anatomies. Conclusions Hybrid revascularization is safe and effective for chronic VA occlusion, with outcomes that depend systematically on lesion morphology. The proposed Type I/II/III classification with the C modifier stratifies technical difficulty and guides strategy selection, while adjunctive stent scaffolding after endarterectomy appears critical for durable patency. These hypothesis-generating findings warrant prospective validation.