{
  "abstract": "Introduction/Purpose The Millipede AspiRation for Revascularization in Stroke Study (MARRS) trial evaluated the Millipede Aspiration System, comprising the superbore 0.088″ (Millipede88) and large-bore 0.070″ (Millipede70) catheters, in patients with large-vessel occlusion (LVO) stroke. The catheter-to-vessel diameter ratio is a key determinant of aspiration thrombectomy success. We performed a post-hoc subgroup analysis to evaluate the impact of M1 vessel diameter on first-pass effect (FPE) mTICI 2c-3 with Millipede88 versus Millipede70.Materials and Methods MARRS was a prospective, multicenter, single-arm study conducted at 22 US and European centers. Patients aged 18-85 years treated within 8 hours of symptom onset were eligible. Although a protocol requirement was to use Millipede88 in vessels ≥2.7 mm, operator discretion resulted in use of both catheters across a range of vessel diameters, enabling post hoc comparison of the intent-to-treat (ITT) population. Imaging and clinical outcomes were independently adjudicated. P-values were derived from a two-sided Fisher’s exact test.Results Among 180 enrolled subjects, 112 had M1 occlusions. Millipede88 was used on the first-pass in 70 cases and Millipede70 in 42. According to Core lab review of procedural angiography, mean M1 vessel diameters were 2.77±0.8mm overall, 2.9±0.9mm for Millipede88, and 2.6±0.5mm for Millipede70. Overall FPE (ITT) was significantly higher with Millipede88 compared with Millipede70 (73% vs 48%, p=0.009*). For diameter strata ≥2.3 mm, Millipede88 demonstrated higher FPE rates (66-79%) compared with Millipede70 (33-50%) ( figure 1). The magnitude of benefit increased with vessel diameter, with absolute differences rising from 8% in vessels <2.3 mm to 43% in vessels ≥2.9 mm. Statistically significant differences were observed at ≥2.3 mm (p=0.01), ≥2.5 mm (p=0.02), ≥2.7 mm (p=0.02), and ≥2.9 mm (p=0.037), while the difference in smaller vessels was non-significant (<2.3 mm, p=1.0). These findings demonstrate a catheter-to-vessel diameter-dependent reperfusion effect.Conclusion In this post-hoc analysis of M1 occlusions in the MARRS study, Millipede88 achieved higher first pass effect than Millipede70. Performance with Millipede70 declined as vessel diameter increased, whereas Millipede88 maintained high FPE rates. These data support the importance of catheter-to-vessel diameter matching in aspiration thrombectomy and suggest that superbore catheters may improve first-pass reperfusion in appropriately sized vessels.Disclosures S. Sheth: 1; C; Balt, Kaneka. 2; C; Balt, Medtronic, Penumbra, Perfuze, Route 92 Medical. 4; C; Motif Neurosciences. T. Bhalla: None. D. Lopes: None. J. Dolia: None. D. Fiorella: 1; C; Rapid Medical, Balt. 2; C; RapidAI, Penumbra, Stryker, Qapel, Phenox, Mentice, Medtronic, J&J, and Arsenal Medical. 4; C; Arsenal Medical, Perfuze and Scientia. S. Zaidi: None. P. Navia: None. T. Kass-Hout: None. A. Al-Bayati: None. R. Bourcier: None. R. Priest: None. W. Guerrero: None. G. Gascou: None. R. Dashti: None. R. Pop: None. A. Aghaebrahim: None. G. Marnat: None. B. Gory: None.Abstract P-013 Figure 1First pass effect by M1 vessel diameter. (A) FPE rates for Millipede70 and Millipede88 across vessel diameter strata. (B) Absolute difference in FPE, showing increasing benefit of the superbore catheter with increasing vessel diameter, *denotes diameter ranges in which the absolute difference in FPE between devices was statistically significant (p < 0.05)",
  "authors": [
    {
      "affiliations": [
        "Neurology, University of Texas Health Science Center at Houston, Heuston, TX"
      ],
      "name": "S Sheth"
    },
    {
      "affiliations": [
        "Neurosurgery, University of Rochester, Rochester, NY"
      ],
      "name": "T Bhalla"
    },
    {
      "affiliations": [
        "Neurosurgery, Advocate Health Care/Advocate Trinity Hospital, Chicago, IL"
      ],
      "name": "D Lopes"
    },
    {
      "affiliations": [
        "Neurology, Grady Memorial Hospital/Emory University School of Medicine, Atlanta, GA"
      ],
      "name": "J Dolia"
    },
    {
      "affiliations": [
        "Neurological Surgery, SUNY SB, Stony Brook, NY"
      ],
      "name": "D Fiorella"
    },
    {
      "affiliations": [
        "Stroke Unit, Vall d’Hebron University Hospital, Barcelona, Spain"
      ],
      "name": "M Requena"
    },
    {
      "affiliations": [
        "Neurology, University of Toledo & ProMedica Toledo Hospital, Toledo, OH"
      ],
      "name": "S Zaidi"
    },
    {
      "affiliations": [
        "Interventional and Diagnostic Neuroradiology, Hospital Universitario La Paz, Madrid, Spain"
      ],
      "name": "P Navia"
    },
    {
      "affiliations": [
        "Neuroradiology, Hopital Purpan, Toulouse, France"
      ],
      "name": "C Cognard"
    },
    {
      "affiliations": [
        "Yale University, New Haven, CT"
      ],
      "name": "C Matouk"
    },
    {
      "affiliations": [
        "The University of Texas Health Science Center at Houston, Houston, TX"
      ],
      "name": "M Nahhas"
    },
    {
      "affiliations": [
        "Galaxy Therapeutics, Inc, Milpitas, CA"
      ],
      "name": "OO Zaidat"
    },
    {
      "affiliations": [
        "Neurology, University of Tennessee health science center, Memphis, TN"
      ],
      "name": "N Goyal"
    },
    {
      "affiliations": [
        "Neurology and Neurosurgery, University of Chicago, Chicago, IL"
      ],
      "name": "T Kass-Hout"
    },
    {
      "affiliations": [
        "Neurology, UTSCHSA Valley Baptist, Harlingen, TX"
      ],
      "name": "A Hassan"
    },
    {
      "affiliations": [
        "Neurology and Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, PA"
      ],
      "name": "A Al-Bayati"
    },
    {
      "affiliations": [
        "Diagnostic and Therapeutic Neuroradiology, University Hospital of Nantes, Nantes, France"
      ],
      "name": "R Bourcier"
    },
    {
      "affiliations": [
        "Interventional Radiology, Oregon Health Science University (OHSU), Portland, OR"
      ],
      "name": "R Priest"
    },
    {
      "affiliations": [
        "Neurosurgery, Brain and Spine, University of South Florida Health, Tampa, FL"
      ],
      "name": "W Guerrero"
    },
    {
      "affiliations": [
        "Neuroradiology, Montpellier University Hospital, Montpellier, France"
      ],
      "name": "G Gascou"
    },
    {
      "affiliations": [
        "Neurological Surgery, Stony Brook University, Stony Brook, NY"
      ],
      "name": "R Dashti"
    },
    {
      "affiliations": [
        "Interventional Neuroradiology, Les Hôpitaux Universitaires de Strasbourg, Strasbourg, France"
      ],
      "name": "R Pop"
    },
    {
      "affiliations": [
        "Baptist Stroke & Cerebrovascular Center, Baptist Health Research Institute, Jacksonville, FL"
      ],
      "name": "A Aghaebrahim"
    },
    {
      "affiliations": [
        "Diagnostic and Interventional Neuroradiology, CHU de Bordeaux, Bordeaux, France"
      ],
      "name": "G Marnat"
    },
    {
      "affiliations": [
        "Ponte vedra, FL"
      ],
      "name": "R Hanel"
    },
    {
      "affiliations": [
        "Department of Diagnostic and Therapeutic Neuroradiology, CHRU-Nancy, Nancy, France"
      ],
      "name": "B Gory"
    },
    {
      "affiliations": [
        "Neurology, Hospital Vall d´Hebron, Barcelona, Spain"
      ],
      "name": "M Ribo"
    },
    {
      "affiliations": [
        "Pittsburgh, PA"
      ],
      "name": "R Nogueira"
    }
  ],
  "title": "P-013 Superbore versus large-bore aspiration in M1 occlusions in MARRS: a vessel diameter-stratified analysis of first pass effect",
  "uid": "ea20d043-e0d1-5326-9b88-cf78e2b638dd"
}