Objective: Whether bridging therapy (intravenous thrombolysis [IVT] followed by endovascular treatment) is superior to IVT alone in minor stroke with large vessel occlusion (LVO) is unknown.
Methods: Multicentric retrospective observational study including, in intention-to-treat, consecutive IVT-treated minor strokes (National Institutes of Health Stroke Scale [NIHSS] ≤ 5) with LVO, with or without additional mechanical thrombectomy. Propensity-score (inverse probability of treatment weighting) was used to reduce baseline between-groups differences. The primary outcome was excellent outcome, that is, modified Rankin score 0 to 1 at 3 months follow-up.
Results: Overall, 598 patients were included (214 and 384 in the bridging therapy and IVT groups, respectively). Following propensity-score weighting, the distribution of baseline clinical and radiological variables was similar across the two patient groups. Compared with IVT alone, bridging therapy was not associated with excellent outcome (odds ratio [OR] = 0.96; 95% confidence interval [CI] = 0.75-1.24; p = 0.76), but was associated with symptomatic intracranial hemorrhage (OR = 3.01; 95% CI = 1.77-5.11; p < 0.0001). Occlusion site was a strong modifier of the effect of bridging therapy on outcome (pinteraction < 0.0001), with bridging therapy associated with higher odds of excellent outcome in proximal M1 (OR = 3.26; 95% CI = 1.67-6.35; p = 0.0006) and distal M1 (OR = 1.69; 95% CI = 1.01-2.82; p = 0.04) occlusions, but with lower odds of excellent outcome for M2 (OR = 0.53; 95% CI = 0.38-0.75; p = 0.0003) occlusions. Bridging therapy was associated with higher rates of symptomatic intracranial hemorrhage in M2 occlusions only (OR = 4.40; 95% CI = 2.20-8.83; p < 0.0001).
Interpretation: Although overall outcomes were similar in intended bridging therapy as compared to intended IVT alone in minor strokes with LVO, our results suggest that intended bridging therapy may be beneficial in M1 occlusions, whereas the benefit-risk profile may favor IVT alone in M2 occlusions. ANN NEUROL 2020 ANN NEUROL 2020;88:160-169.
© 2020 American Neurological Association.