Factors Associated With Fast Early Infarct Growth in Patients With Acute Ischemic Stroke With a Large Vessel Occlusion
Pierre Seners, Nicole Yuen, Jean‐Marc Olivot, Michael Mlynash, Jeremy J. Heit, Sören Christensen, José Bernardo Escribano Paredes, Emmanuel Carrera, Davide Strambo, Patrik Michel, Alexander Salerno, Max Wintermark, Hui Chen, Jean‐François Albucher, Christophe Cognard, Igor Sibon, Michaël Obadia, Julien Savatovsky, Maarten G. Lansberg, Gregory W. Albers, for Mismatch Prevalence
Abstract
BACKGROUND AND OBJECTIVES: The optimal methods for predicting early infarct growth rate (EIGR) in acute ischemic stroke with a large vessel occlusion (LVO) have not been established. We aimed to study the factors associated with EIGR, with a focus on the collateral circulation as assessed by the hypoperfusion intensity ratio (HIR) on perfusion imaging, and determine whether the associations found are consistent across imaging modalities. METHODS: Retrospective multicenter international study including patients with anterior circulation LVO-related acute stroke with witnessed stroke onset and baseline perfusion imaging (MRI or CT) performed within 24 hours from symptom onset. To avoid selection bias, patients were selected from (1) the prospective registries of 4 comprehensive stroke centers with systematic use of perfusion imaging and including both thrombectomy-treated and untreated patients and (2) 1 prospective thrombectomy study where perfusion imaging was acquired per protocol, but treatment decisions were made blinded to the results. EIGR was defined as infarct volume on baseline imaging divided by onset-to-imaging time and fast progressors as EIGR ≥10 mL/h. The HIR, defined as the proportion of time-to-maximum (Tmax) >6 second with Tmax >10 second volume, was measured on perfusion imaging using RAPID software. The factors independently associated with fast progression were studied using multivariable logistic regression models, with separate analyses for CT- and MRI-assessed patients. RESULTS: = 0.030, respectively). DISCUSSION: The HIR is the primary factor associated with fast infarct progression, regardless of imaging modality. These results have implication for neuroprotection trial design, as well as informing triage decisions at primary stroke centers.