{
  "abstract": "Background Predictors of futile recanalization and the no-reflow phenomenon remain poorly defined. Incomplete microcirculatory reperfusion underlies a substantial proportion of unfavorable outcomes despite successful large-vessel recanalization. The Thrombolysis in Cerebral Infarction (TICI) score reflects macrovascular reperfusion but does not adequately capture microvascular perfusion. Early post-thrombectomy hypoperfusion, represented here as Tmax>6 second volume, has emerged as a potential surrogate marker of microvascular perfusion and predictor of long-term outcomes. The hypoperfusion intensity ratio (HIR) is a known predictor of infarct growth, but its relationship to post-thrombectomy microvascular perfusion is not well established. We sought to determine whether baseline HIR predicts early post-thrombectomy Tmax>6 volume.Methods We performed a subgroup analysis of the CRISP2 dataset, a prospective, NIH-funded, multicenter study evaluating factors associated with infarct growth during interhospital transfer. Patients with baseline perfusion imaging, successful macrovascular reperfusion (TICI ≥2b) and follow-up perfusion imaging within 24 hours of thrombectomy were included. HIR is defined as the ratio of Tmax >10s/Tmax >6s volumes on perfusion imaging (lower HIR indicates favorable brain perfusion). Linear regression analyses were performed to assess associations between baseline HIR, TICI grade, and early follow-up Tmax>6 volume. Three models were evaluated: TICI alone, HIR alone, and a multivariable model including both predictors.Results Fifty patients met inclusion criteria. In univariable analysis, TICI grade was not significantly associated with Tmax>6 volume after thrombectomy (p=0.24). In contrast, baseline HIR was significantly associated with Tmax>6 volume (8.8 mL increase per 0.1 increase in HIR, p=0.008), with higher HIR corresponding to greater residual hypoperfusion. In the multivariable model, baseline HIR remained independently associated with Tmax>6 volume (8.5 mL increase per 0.1 increase in HIR, p=0.012), while TICI grade was not a significant predictor (TICI 2c vs 2b: p=0.15; TICI 3 vs 2b: p=0.25).Conclusions Baseline HIR is independently associated with early post-thrombectomy Tmax>6 volume, which suggests that baseline perfusion status influences microvascular reperfusion beyond macrovascular angiographic success. These findings support the role of HIR as a potential predictor of futile recanalization and highlight the importance of incorporating baseline imaging biomarkers into prognostic models following endovascular therapy.Disclosures J. Sim: None. P. Konduri: None. N. Krothapalli: None. M. Lansberg: None.",
  "authors": [
    {
      "affiliations": [
        "Stanford University Medical Center, Palo Alto, CA"
      ],
      "name": "J Sim"
    },
    {
      "affiliations": [
        "Stanford University Medical Center, Palo Alto, CA"
      ],
      "name": "P Konduri"
    },
    {
      "affiliations": [
        "Stanford University Medical Center, Palo Alto, CA"
      ],
      "name": "N Krothapalli"
    },
    {
      "affiliations": [
        "Interventional Neuroradiology, Stanford University, Stanford, CA"
      ],
      "name": "J Heit"
    },
    {
      "affiliations": [
        "Stanford University Medical Center, Palo Alto, CA"
      ],
      "name": "M Lansberg"
    }
  ],
  "title": "E-187 Beyond TICI: baseline hir predicts residual hypoperfusion after thrombectomy",
  "uid": "ef14cfce-c18c-5846-8e24-5338bdd212e2"
}