Ischemic Postconditioning in Patients With Acute Stroke With Successful Recanalization After Endovascular Therapy: A Pilot Randomized Controlled Trial

BACKGROUND: Ischemia-reperfusion injury contributes to continued infarct growth despite successful recanalization. Ischemic postconditioning (IPostC) reduces infarct size in preclinical models, but its therapeutic effect as an adjunct to endovascular thrombectomy remains uncertain. We investigated whether IPostC performed after successful recanalization reduces infarct growth in patients with acute ischemic stroke. METHODS: This single-center, prospective, randomized, open-label trial with blinded end point assessment was conducted at Tianjin Huanhu Hospital between September 2024 and May 2025. Patients with acute ischemic stroke who underwent endovascular thrombectomy within 24 hours of symptom onset or last known well, had a baseline National Institutes of Health Stroke Scale score ≥6 and a prestroke modified Rankin Scale score ≤2, and achieved successful recanalization after endovascular thrombectomy were randomly assigned to the IPostC or control group. IPostC consisted of 4 cycles of 2-minute balloon inflation followed by 2-minute deflation, with the balloon positioned at the original intracranial arterial occlusion site. The primary outcome was infarct growth from baseline to 48-hour magnetic resonance imaging (MRI). Secondary outcomes included infarct volume on immediate postprocedure MRI (within 2 hours) and on 48-hour MRI; early infarct growth and late infarct growth; serial National Institutes of Health Stroke Scale scores during hospitalization; and modified Rankin Scale score at 90 days. Primary and secondary outcomes were analyzed in the intention-to-treat population using unadjusted between-group comparisons. RESULTS: Sixty patients were enrolled, with 30 randomly assigned to each group. Infarct growth from baseline to 48-hour MRI was lower with IPostC than with control (median difference, −8.7 mL [95% CI, −17.1 to −1.4]; P =0.015). In the serial MRI subgroup (n=30; 15 per group), early infarct growth was also lower with IPostC (median difference, −3.2 mL [95% CI, −8.7 to −0.1]; P =0.045). Patients in the IPostC group had a lower National Institutes of Health Stroke Scale score at 24 hours (median difference, −3.0 [95% CI, −5.0 to −1.0]; P =0.005). The 90-day modified Rankin Scale distribution did not differ significantly between groups (common odds ratio, 1.1 [95% CI, 0.4–2.6]; P =0.921). CONCLUSIONS: In this pilot randomized trial, IPostC performed after successful recanalization reduced infarct growth in patients with acute ischemic stroke due to large-vessel occlusion. These findings require confirmation in larger randomized trials. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT06545734.