Intravenous thrombolysis in acute mild non-disabling ischemic stroke: A retrospective cohort study.

BACKGROUND: The benefit of intravenous thrombolysis (IVT) in patients with acute mild, non-disabling ischemic stroke remains uncertain. We evaluated the real-world effectiveness and safety of IVT and explored heterogeneity of treatment effects in prespecified subgroups.

METHODS: We conducted a single-center retrospective observational cohort study of consecutive adults with acute mild, non-disabling ischemic stroke treated at the Stroke Center of the Fifth Affiliated Hospital of Sun Yat-sen University (March 2019-October 2023). Eligible patients presented within 6 h, had baseline NIHSS ≤ 5 with each item ≤ 1 (and 0 on consciousness items), and had no deficits perceived as potentially disabling. Patients receiving endovascular therapy after IVT or scheduled cerebrovascular intervention within 3 months were excluded. The primary outcome was excellent functional outcome (90-day mRS 0-1). Secondary outcomes were functional independence (90-day mRS 0-2) and early neurological deterioration (END; NIHSS increase>2 within 7 days). Safety outcomes included hemorrhagic transformation (HT) and symptomatic intracranial hemorrhage (sICH). Group comparisons used standard univariable tests; prespecified subgroup analyses were performed.

RESULTS: Among 228 patients (mean age 60.7 ± 12.5 years; 66.3% male), 185 received IVT and 43 did not. Baseline characteristics were similar, except for a slightly higher median admission NIHSS in the IVT group (2 [IQR 1-2] vs 1 [IQR 1-2]; P < 0.001). At 90 days, mRS 0-1 occurred in 84.9% with IVT versus 74.4% without IVT (P = 0.117); functional independence (mRS ≤ 2) was 94.1% vs 90.7% (P = 0.492). END occurred in 12.4% vs 25.6% (P = 0.054). Any HT occurred in 5.9% vs 4.7% (P = 0.542); sICH was rare (1.1% vs 0.0%; P = 0.658). Subgroup analyses suggested a potential benefit of IVT in patients aged ≥ 65 years for achieving mRS 0-1.

CONCLUSIONS: In acute mild, non-disabling ischemic stroke, IVT was not associated with increased hemorrhagic complications and did not significantly improve overall 90-day excellent functional outcome. Patients aged ≥ 65 years may derive greater functional benefit from IVT, warranting confirmation in larger prospective studies.