Perfusion Imaging and Clinical Outcome in Acute Ischemic Stroke with Large Core
Pierre Seners, Catherine Oppenheim, Guillaume Turc, Jean‐François Albucher, Adrien Guenego, Nicolas Raposo, Sören Christensen, Lionel Calvière, Alain Viguier, Jean Darcourt, Anne‐Christine Januel, Michael Mlynash, Agnès Sommet, Claire Thalamas, Igor Sibon, Vanessa Rousseau, Thomas Tourdias, Patrice Ménégon, Fabrice Bonneville, Mikaël Mazighi, Sylvain Charron, Laurence Legrand, Christophe Cognard, Gregory W. Albers, Jean‐Claude Baron, Jean‐Marc Olivot, the FRAME investigators
Abstract
Objective Mechanical thrombectomy (MT) is not recommended for acute stroke with large vessel occlusion (LVO) and a large volume of irreversibly injured tissue (“core”). Perfusion imaging may identify a subset of patients with large core who benefit from MT. Methods We compared two cohorts of LVO‐related patients with large core (>50 ml on diffusion‐weighted‐imaging or CT‐perfusion using RAPID), available perfusion imaging, and treated within 6 hours from onset by either MT + Best Medical Management (BMM) in one prospective study, or BMM alone in the pre‐MT era from a prospective registry. Primary outcome was 90‐day modified Rankin Scale ≤2. We searched for an interaction between treatment group and amount of penumbra as estimated by the mismatch ratio (MMRatio = critical hypoperfusion/core volume). Results Overall, 107 patients were included (56 MT + BMM and 51 BMM): Mean age was 68 ± 15 years, median core volume 99 ml (IQR: 72–131) and MMRatio 1.4 (IQR: 1.0–1.9). Baseline clinical and radiological variables were similar between the two groups, except for a higher intravenous thrombolysis rate in the BMM group. The MMRatio strongly modified the clinical outcome following MT ( p interaction < 0.001 for continuous MMRatio); MT was associated with a higher rate of good outcome in patients with, but not in those without, MMRatio>1.2 (adjusted OR [95% CI] = 6.8 [1.7–27.0] vs 0.7 [0.1–6.2], respectively). Similar findings were present for MMRatio ≥1.8 in the subgroup with core ≥70 ml. Parenchymal hemorrhage on follow‐up imaging was more frequent in the MT + BMM group regardless of the MMRatio. Interpretation Perfusion imaging may help select which patients with large core should be considered for MT. Randomized studies are warranted. ANN NEUROL 2021;90:417–427