{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,11]],"date-time":"2026-04-11T17:49:03Z","timestamp":1775929743724,"version":"3.50.1"},"reference-count":24,"publisher":"BMJ","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["J NeuroIntervent Surg"],"accepted":{"date-parts":[[2026,3,13]]},"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Endovascular thrombectomy (EVT) is the standard of care for large vessel occlusion stroke, yet technical failure persists in a significant minority of cases. Intracranial atherosclerotic disease (ICAD) is a recognized driver of failure in Asian populations; its prevalence in Western cohorts is underestimated. We aimed to classify mechanisms of technical failure in a large cohort and investigate the impact of both unrecognized ICAD and anatomical access difficulties.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We analyzed 2467 consecutive single-center EVT procedures retrospectively. Failure was defined as final modified Treatment In Cerebral Infarction (mTICI) &lt;2b or no angiographic improvement. Failures were classified into three categories: type 1 (access failure), type 2 (clot accessed but no durable reperfusion), and type 3 (aborted\/other). Type 2 failures were adjudicated by consensus to identify features suggestive of ICAD.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Recanalization failure occurred in 313 patients (12.7%); type 1 accounted for 40 (12.8%), type 2 occurred in 127 (40.6%), and 146 (46.6%) were type 3. Baseline age and stroke severity were similar between successful and failed groups, but failure was associated with significantly longer procedure times (median 60 vs 30\u2009min, P&lt;0.001) and almost threefold higher in-hospital mortality (29.4% vs 11.0%, P&lt;0.001). Among type 2 failures, 18.1% were adjudicated as likely underlying ICAD and 4.7% as possible ICAD. While overall failure rates declined from 23.0% (2012\u20132015)\u2009to 11.2% (2019\u20132023) driven by improvements in M1 middle cerebral artery recanalization, the incidence of type 1 failures did not significantly improve over time (P=0.20), representing a persistent unmet technical need.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Despite technical advances, procedural failure remains a distinct event with catastrophic outcomes. Up to 22.8% of retrieval failures in this Western cohort were attributable to likely\/possible underlying ICAD rather than refractory emboli.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/jnis-2026-024990","type":"journal-article","created":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T17:20:30Z","timestamp":1774632030000},"page":"jnis-2026-024990","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Mechanisms, predictors, and clinical impact of failed recanalization: a large cohort analysis"],"prefix":"10.1136","clinical-trial-number":[{"clinical-trial-number":"nct06472336","registry":"10.18810\/clinical-trials-gov"}],"author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-9348-1342","authenticated-orcid":false,"given":"Richard","family":"Bruen","sequence":"first","affiliation":[{"name":"Diagnostic and Interventional Neuroradiology Department, Beaumont Hospital, Dublin, 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