Radially adjustable Tigertriever demonstrates higher reperfusion compared to self-expanding stent-retrievers during mechanical thrombectomy of large vessel occlusions: a systematic review and meta-analysis

Introduction Mechanical thrombectomy is the standard of care for acute ischemic stroke due to large vessel occlusions. Conventional self-expanding stent retrievers (SE-SRs) deploy with fixed radial force, whereas Tigertriever is a radially adjustable operator-controlled device that allows tailored expansion and modulation of vessel wall pressure. This study systematically compared the efficacy and safety of Tigertriever with SE-SRs in large vessel occlusion thrombectomy. Methods A systematic search of PubMed, Cochrane, Embase, and ClinicalTrials.gov was conducted in line with PRISMA guidelines. Eligible studies compared Tigertriever with SE-SRs, with outcomes including rate of successful reperfusion (mTICI ≥ 2b), procedural adverse events (PAEs; composite of procedure-related vasospasm, dissection, perforation, distal emboli, emboli to new territory, and subarachnoid hemorrhage), symptomatic intracranial hemorrhage (sICH) within 24 h post-procedure, functional independence (mRS 0–2) at 90 days and all-cause mortality at 90 days. Odds ratios (OR) with 95% confidence intervals (CI) were pooled using the Mantel–Haenszel method. Risk of bias was assessed using ROBINS-I, and certainty of evidence using the GRADE approach. Results Three retrospective cohort studies with 476 patients (210 Tigertriever, 266 SE-SR) were included. Target intracranial vessel occlusion locations were internal carotid artery (ICA), middle cerebral artery (MCA) M1, MCA M2 and basilar artery. Tigertriever achieved significantly higher successful reperfusion compared with SE-SRs [82.8% vs. 77.8%; OR 1.74 (1.07–2.83); p = 0.03; I 2 = 0%]. There was a trend towards fewer PAEs, but the difference did not reach statistical significance [17.1% vs. 27.4%; OR 0.72 (0.44–1.16); p = 0.17; I 2 = 0%]. Rates of sICH within 24 h, functional independence at 90 days and mortality at 90 days were similar. The overall risk of bias was low to moderate. GRADE-assessed certainty for different outcomes was overall moderate. Conclusion In this exploratory meta-analysis of retrospective cohorts, Tigertriever was associated with significantly higher reperfusion rates, while safety and functional outcomes appeared comparable between groups. Findings should be interpreted cautiously given study-level heterogeneity, limited sample size, inconsistent procedural reporting, and the observational nature of included studies. Systematic review registration https://www.crd.york.ac.uk/PROSPERO/view/CRD420251161491 . The protocol for this meta-analysis was registered on PROSPERO. ID: CRD420251161491.