Effectiveness and Safety of Mechanical Thrombectomy in Large-Vessel-Occlusion Mild Stroke: Insights from the ASSIST Registry

Sophia Hohenstatt; Dominik F Vollherbst; Salvador Miralbés; Bharath Naravetla; Alejandro Spiotta; Christian Loehr; Mario Martínez-Galdámez; Ryan McTaggart; Luc Defreyne; Pedro Vega; Osama O Zaidat; Paul Jenkins; Sergio Lucio Vinci; David S Liebeskind; Rishi Gupta; Markus A Möhlenbruch; Agostino Tessitore; ASSIST Investigators

doi:10.3174/ajnr.A8613

Effectiveness and Safety of Mechanical Thrombectomy in Large-Vessel-Occlusion Mild Stroke: Insights from the ASSIST Registry

AJNR Am J Neuroradiol. 2024 Dec 3:ajnr.A8613. doi: 10.3174/ajnr.A8613. Online ahead of print.

Authors

Sophia Hohenstatt¹, Dominik F Vollherbst¹, Salvador Miralbés¹, Bharath Naravetla¹, Alejandro Spiotta¹, Christian Loehr¹, Mario Martínez-Galdámez¹, Ryan McTaggart¹, Luc Defreyne¹, Pedro Vega¹, Osama O Zaidat¹, Paul Jenkins¹, Sergio Lucio Vinci¹, David S Liebeskind¹, Rishi Gupta¹, Markus A Möhlenbruch¹, Agostino Tessitore; ASSIST Investigators

Affiliation

¹ From the Department of Department of Neuroradiology, University Hospital Heidelberg (S.H.; D. F. V.; M. A. M.); Neuroradiology, Hospital Son Espases, Mallorca, Spain (S.M.); Interventional Neurology, McLaren Regional Medical Center, Flint, Michigan, USA (B.N.); Interventional Neurology, McLaren Regional Medical Center, Macomb, Michigan, USA (B.N.); Neurosurgery, Medical University of South Carolina, Charleston, SC, USA (A.S.); Radiology and Neuroradiology, Klinikum Vest Recklinghausen, Recklinghausen, Germany (C.L.); Interventional Neuroradiology/Endovascular Neurosurgery, Hospital Clínico Universitario de Valladolid, Valladolid, Spain (M.M.G.); Interventional Neuroradiology, Rhode Island Hospital, Providence, Rhode Island, USA (R.M.T.); Vascular and Interventional Radiology, Ghent University Hospital, Ghent, Belgium (L.D.); Radiology, Hospital Universitario Central de Asturias-HUCA, Oviedo, Spain (P.V.); Neuroscience Department, Bon Secours Mercy Health St. Vincent Medical Center, Toledo, Ohio, USA (O.O.Z); Stryker Neurovascular, Fremont, California, USA (P.J.); Neuroradiology Unit, Radiology Department, University Hospital "G. Martino" Messina, Messina, Italy (S.L.V., A.T.); Department of Neurology and Comprehensive Stroke Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, USA (D.S.L.); Wellstar Medical Group, Neurosurgery, WellStar Health System, Marietta, Georgia, USA (R.G.).

PMID: 39627006
DOI: 10.3174/ajnr.A8613

Abstract

Background and purpose: Mechanical thrombectomy (MT) is effective for acute ischemic stroke, yet its indication in mild stroke remains unclear. This study evaluates MT's effectiveness and safety in low NIHSS patients and assesses different MT strategies' impact on procedural success and clinical outcomes.

Materials and methods: Data from the ASSIST Registry were analyzed, categorizing patients with large vessel occlusion of the anterior circulation into mild (NIHSS≤5) and moderate-severe (NIHSS>5) stroke groups. Baseline characteristics, procedural parameters, angiographic and imaging outcomes, clinical outcomes, and safety endpoints were compared. Within the mild stroke subgroup, outcomes were compared between different MT techniques.

Results: Among 1360 patients with LVO, 122 had minor ischemic strokes (9%). Mild stroke patients had high rates of excellent functional outcomes (mRS 0-1) at 90 days (77.1%) and functional independence (mRS 0-2) (85.7%). Procedural success rates were similar between NIHSS groups, while safety outcomes, except mortality, were comparable. No statistically significant differences were observed in treatment techniques within the mild stroke subgroup. Significant predictors of early neurological deterioration (END) in mild stroke patients were the total number of passes (OR 1.49, 95% CI 1.01 - 2.19, P=.04) and total procedure time (OR 1.02, 95% CI 1.01 - 1.04, P=.01). Patients with END were more likely to have an unfavorable functional outcome (mRS 3-6) at 90 days (89% vs. 6%, P<0.001).

Conclusions: MT is effective and safe in mild stroke patients. Procedural success did not vary among MT techniques in mild stroke. The total number of passes predicts END, which suggests a causal pathway that requires further exploration.

Abbreviations: AIS = acute ischemic stroke; BMT = best medical treatment; DA = direct aspiration; END = early neurological deterioration; EVT = endovascular treatment; LVO = large vessel occlusion; MT = mechanical thrombectomy; SAEs = serious adverse events; sICH = symptomatic intracranial hemorrhage; SR = stent retriever.