Perfusion Imaging and Clinical Outcome in Acute Minor Stroke With Large Vessel Occlusion
Authors: Seners Pierre , Arquizan Caroline , Fontaine Louis , Ben Hassen Wagih , Heldner Mirjam R. , Strambo Davide , Nagel Simon , Carrera Emmanuel , Mechtouff Laura , McCullough-Hicks Margy , Mohammaden Mahmoud H. , Cottier Jean-Philippe , Henon Hilde , Aignatoaie Andreea , Laksiri Nadia , Papassin Jérémie , Lucas Ludovic , Garnier Pierre , Triquenot Aude , Mione Gioia , Hajdu Steven , Costalat Vincent , Potreck Arne , Detante Olivier , Bonneville Fabrice , Berthezene Yves , Bracard Serge , Sibon Igor , Bricout Nicolas , Boutet Claire , Mordasini Pasquale , Michel Patrik , Oppenheim Catherine , Olivot Jean-Marc , Nogueira Raul G. , Albers Gregory W. , Baron Jean-Claude , Turc Guillaume , Cognard Christophe , Marnat Gaultier , Menegon Patrice , Ledure Sylvain , Dargazanli Cyril , Cho Tae-Hee , Nighoghossian Norbert , Eker Omer , Gouttard Sylvain , Haussen Diogo , Debiais Séverine , Charron Vladimir , Charron Nicolas , Leys Didier , Ozsancak Canan , Delpech Mathilde , Brunel Hervé , Papagiannaki Chrysanti , Girardin Emmanuel , Richard Sébastien , Gory Benjamin , Zbinden Martin , Dobrocky Tomas , Ringelb Peter , Möhlenbruch Markus 
Published: July 2022

Background:
Whether bridging therapy (intravenous thrombolysis [IVT] followed by mechanical thrombectomy) is superior to IVT alone in minor stroke with large vessel occlusion is unknown. Perfusion imaging may identify subsets of large vessel occlusion–related minor stroke patients with distinct response to bridging therapy.

Methods:
We conducted a multicenter international observational study of consecutive IVT-treated patients with minor stroke (National Institutes of Health Stroke Scale score ≤5) who had an anterior circulation large vessel occlusion and perfusion imaging performed before IVT, with a subset undergoing immediate thrombectomy. Propensity score with inverse probability of treatment weighting was used to account for baseline between-groups differences. The primary outcome was 3-month modified Rankin Scale score 0 to 1. We searched for an interaction between treatment group and mismatch volume (critical hypoperfusion–core volume).

Results:

Overall, 569 patients were included (172 and 397 in the bridging therapy and IVT groups, respectively). After propensity-score weighting, the distribution of baseline variables was similar across the 2 groups. In the entire population, bridging was associated with lower odds of achieving modified Rankin Scale score 0 to 1: odds ratio, 0.73 [95% CI, 0.55–0.96];
P
=0.03. However, mismatch volume modified the effect of bridging on clinical outcome (
P
interaction
=0.04 for continuous mismatch volume); bridging was associated with worse outcome in patients with, but not in those without, mismatch volume <40 mL (odds ratio, [95% CI] for modified Rankin Scale score 0–1: 0.48 [0.33–0.71] versus 1.14 [0.76–1.71], respectively). Bridging was associated with higher incidence of symptomatic intracranial hemorrhage in the entire population, but this effect was present in the small mismatch subset only (
P
interaction
=0.002).

Conclusions:
In our population of large vessel occlusion-related minor stroke patients, bridging therapy was associated with lower rates of good outcome as compared with IVT alone. However, mismatch volume was a strong modifier of the effect of bridging therapy over IVT alone, notably with worse outcome with bridging therapy in patients with mismatch volume ≤40 mL. Randomized trials should consider adding perfusion imaging for patient selection.