Safety and efficacy of mechanical thrombectomy for acute ischemic stroke with volume over 50 mL and significant perfusion mismatch.

Background: This study aims to address the safety and efficacy of mechanical thrombectomy (MT) in acute ischemic stroke with an established infarction equal to or >50 mL with a significant difference between penumbra and established infarction detected by perfusion cerebral computed tomography (CT) with the Rapid® system. Methods: This was a retrospective case-control study. Patients diagnosed with established and extensive ischemic stroke, defined by an ischemic volume equal to or >50 mL on CT or magnetic resonance imaging perfusion using the RAPID® system, were examined. The intervention group received endovascular interventional treatment with or without recombinant tissue plasminogen activator (rt-PA) in addition to standard therapy, and the control group received conservative treatment with or without rt-PA plus standard therapy. Results: A total of 59 patients were enrolled, including 38 in the intervention group and 21 in the control group. Baseline characteristics were similar between groups. Patient National Institutes of Health Stroke Scale at discharge was significantly different between the control (median 30, interquartile range [IQR] 13) and intervention group (median 8, IQR 14) (P < 0.001). Modified Rankin scale (mRS) scores were significantly different at discharge between intervention (median mRS 2, IQR 3) and controls (median mRS 5, IQR 1) (P = 0.002). These mRS differences remained significant at 90 days, with median (IQR) values of 2 (2.75) and 5 (1), respectively (P < 0.001). Conclusion: MT is safe and effective for large-core ischemic strokes with significant perfusion mismatch, leading to better functional outcomes without significant complications compared to the best medical treatment.

Thrombectomy With the pRESET vs Solitaire Stent Retrievers as First-Line Large Vessel Occlusion Stroke Treatment: A Randomized Clinical Trial.

Importance: Stent retriever-based thrombectomy is highly beneficial in large vessel occlusion (LVO) strokes. Many stent retriever designs are currently available, but comparison of these technologies in well-conducted studies is lacking. Objective: To determine whether thrombectomy for LVO stroke with the pRESET stent retriever is noninferior to treatment with the Solitaire stent retriever. Design, Setting, and Participants: This study was a multicenter, prospective, randomized, controlled, open-label, adaptive, noninferiority trial with blinded primary end point evaluation. Between October 2019 and February 2022, multicenter participation occurred across 19 research hospitals and/or universities in the US and 5 in Germany. Patients with LVO stroke were enrolled and included up to 8 hours after symptom onset. Interventions: Patients underwent 1:1 randomization to thrombectomy with the pRESET or Solitaire stent retriever. Main Outcomes and Measures: The primary outcome was the difference in the rate of 90-day functional independence across the 2 devices, using a -12.5% noninferiority margin for the lower bound of the 1-sided 95% CI of the difference between pRESET and Solitaire retrievers. Results: Of 340 randomized patients, 170 (50.0%) were female, and the median (IQR) age was 73.0 (64.0-82.0) years. The study procedure was completed in 322 of the 340 randomized patients. The primary end point of 90-day functional independence was achieved by 95 patients (54.9%; 95% CI, 48.7-61.1) in the pRESET group and in 96 (57.5%; 95% CI, 51.2-63.8) in the Solitaire group (absolute difference, -2.57%; 95% CI, -11.42 to 6.28). As the lower bound of the 95% CI was greater than -12.5%, the pRESET retriever was deemed noninferior to the Solitaire retriever. The noninferiority of pRESET over Solitaire was also observed in the secondary clinical end point (90-day shift in modified Rankin Scale score) and in both angiographic end points (Expanded Treatment in Cerebral Infarction [eTICI] score of 2b50 or greater within 3 passes: 146 of 173 [84.4%] vs 149 of 167 [89.2%]; absolute difference, -4.83%; 95% CI, -10.84 to 1.19; eTICI of 2c or greater following the first pass: 76 of 173 [43.7%] vs 74 of 167 [44.3%]; absolute difference, -0.63%; 95% CI, -9.48 to 8.21). Symptomatic intracranial hemorrhage occurred in 0 patients in the pRESET group and 2 (1.2%) in the Solitaire group. Mortality occurred in 25 (14.5%) in the pRESET group and in 24 (14.4%) in the Solitaire group at 90 days. Findings of the per-protocol and as-treated analyses were in concordance with findings of the intention-to-treat analysis. Conclusions and Relevance: In this study, among patients with LVO stroke, thrombectomy with the pRESET stent retriever was noninferior to thrombectomy with the Solitaire stent retriever. Findings suggest that pRESET offers a safe and effective option for flow restoration and disability reduction in patients with LVO stroke.

Multicenter study of safety in stenting for symptomatic vertebral artery origin stenosis: results from the Society of Vascular and Interventional Neurology Research Consortium.

PURPOSE: To assess the safety and efficacy of vertebral artery origin angioplasty and stenting for stroke prevention in a multicenter clinical experience. METHODS: Patients with symptomatic vertebral artery origin stenosis (VAOS) were gathered from the Society of Vascular and Interventional Neurology Research Consortium. Demographic, clinical, and procedural data were collected. The main outcome measure was procedural and peri-procedural risks of stroke, transient ischemic attack (TIA), or death at 1 and 3 months. Logistic regression analysis was used to assess covariates associated with future restenosis. RESULTS: A total of 148 patients were included with mean age of 66.2 ± 11.5; 74% men and 77% Caucasian. One patient (.8%) had a stroke at 1 month and 5 of 96 (5.2%) patients had TIA at 3 months. There were no immediate procedural events or deaths. The mean angiographic pre-treatment stenosis was 80.5 ± 12.7%, which was reduced to 5.3 ± 9.1% after stent deployment. Follow-up angiography showed 15.5% of patients had significant restenosis (≥50%). Predictors of restenosis included age (OR 3.08; 95% CI 1.01, 9.41) and smoking (OR 3.10; 95% CI 1.12, 8.64). CONCLUSIONS: Endovascular intervention of VAOS is associated with low peri-procedural complication rates. Restenosis remains a concern; age and smoking predicted future restenosis.

Defining amino acid residues involved in DNA-protein interactions and revelation of 3'-exonuclease activity in endonuclease V.

Endonuclease V is an enzyme that initiates a conserved DNA repair pathway by making an endonucleolytic incision at the 3' side one nucleotide from a deaminated base lesion. Site-directed mutagenesis analysis was conducted at seven conserved motifs of the thermostable Thermotoga maritima endonuclease V to probe for residues that affect DNA-protein interactions. Y80, G83, and L85 in motif III, H116 and G121 in motif IV, A138 in motif V, and S182 in motif VI affect binding of both the double-stranded inosine-containing DNA substrate and the nicked double-stranded inosine-containing DNA product, resulting in multiple enzymatic turnovers. The substantially reduced DNA cleavage activity observed in G113 in motif IV and G136 in motif V can be partly attributed to their defect in metal cofactor coordination. Alanine substitution at amino acid 118 primarily reduces the level of binding to the nicked product, suggesting that R118 plays a significant role in postcleavage DNA-protein interaction. Binding and cleavage analyses of multiple mutants at positions Y80 and H116 underscore the role these residues play in protein-DNA interaction and implicate their potential involvement as a hydrogen bond donor in recognition of deaminated DNA bases. DNA cleavage analysis using mutants defective in DNA binding reveals a novel 3'-exonuclease activity in endonuclease V. An alternative model is proposed that entails lesion specific cleavage and endonuclease to 3'-exonuclease mode switch by endonuclease V for removal of deaminated base lesions during endonuclease V-mediated repair.