Background The efficacy of intravenous thrombolysis (IVT) versus early antiplatelet therapy (APT) in small artery occlusion (SAO) stroke remains debated. Methods Ischaemic stroke (IS) patients with SAO who received IVT or early APT without IVT≤4.5 hours from stroke onset were screened from a prospective multicentre IS registry study from 1 January to 1 June 2021. The primary outcome was unfavourable functional outcome (FO) at 3 months. The secondary outcome was early neurological deterioration (END). The safety outcome was symptomatic intracerebral haemorrhage (sICH). Results There were 1125 SAO patients with 394 receiving IVT. 411 patients (36.5%) exhibited unfavourable FO, and sICH occurred in 3 cases (0.27%), all in IVT group, at the follow-up. END was observed in 213 patients (18.9%). After propensity score matching and multivariable adjustment, IVT significantly reduced the likelihood of unfavourable FO at 3 months (aOR 0.447, 95% CI 0.305 to 0.656), but no significant difference was found in END (aOR 0.867, 95% CI 0.569 to 1.321). Clustering analysis identified two distinct phenotypes: phenotype 0 (characterised by traditional cardiovascular risk factors) and phenotype 1 (marked by prominent inflammatory markers). A significant treatment-by-phenotype interaction was observed (p=0.002), with a comparable magnitude of benefit in phenotype 0 (aOR 0.405, 95% CI 0.244 to 0.673) compared with phenotype 1 (aOR 0.414, 95% CI 0.218 to 0.783). Conclusion IVT significantly reduced the likelihood of unfavourable FO at 3 months in SAO patients but did not significantly reduce END. Patients with traditional risk factors may benefit more from IVT than those with elevated inflammatory markers. Trial registration number ChiCTR2100045258.
Zhang et al. (Thu,) studied this question.