Abstract / Summary
Background Despite high recanalization rates with endovascular thrombectomy for large vessel occlusion stroke, a large proportion of patients remain disabled. This study aims to investigate the clinical impact of persistent hypoperfusion that was detected immediately after recanalization. Methods In this multicenter retrospective study of patients with large vessel occlusion with near‐complete or complete recanalization, perfusion maps were generated from post‐recanalization digital subtraction angiography. Focal hypoperfusion within the ischemic territory was detected and categorized as regional or cortical according to spatial distribution. The primary outcome was 90‐day functional independence (modified Rankin Scale 0 to 2). The associations of no‐reflow and outcomes were examined by multivariable logistic regression. Results Among 375 patients (median age 69 [interquartile range 57–77] years; 67.5% men), persistent hypoperfusion was detected in 29.6% of patients. Patients with hypoperfusion had higher baseline National Institutes of Health Stroke Scale (median 14 versus 12, P =0.076) and more thrombectomy passes ( P =0.021). The presence of persistent hypoperfusion was strongly associated with reduced functional independence (adjusted odds ratio [aOR]=0.23, 95% CI 0.13–0.39, P <0.001), higher rates of hemorrhagic transformation (aOR=1.88, 95% CI 1.14–3.11; P =0.013) and symptomatic intracranial hemorrhage (aOR=2.95, 95% CI 1.20–7.23; P =0.018). Quantitative analysis revealed minimum regional cerebral blood flow as a key factor of functional outcome (aOR=1.67, 95% CI 1.07–2.60; P =0.023). There is no significant agreement with 24‐hour computed tomography perfusion‐defined hypoperfusion (κ=0.106, P =0.524). Conclusions Persistent hypoperfusion could be detected immediately post‐recanalization in one‐third of successfully treated large vessel occlusion strokes. The adverse impact to functional outcome highlights its potential as an intraprocedural biomarker for future adjunctive therapies.