Intra-arterial albumin following endovascular reperfusion for large vessel occlusion stroke: a prospective cohort study

BACKGROUND: Preclinical reports suggest that intra-arterial (IA) 20% albumin may have neuroprotective effects. A 3+3 dose-escalation pilot clinical trial preliminarily confirmed the safety and feasibility of doses up to 0.6 g/kg. Based on these findings, we aimed to evaluate the safety and explore the potential efficacy of adjunctive IA albumin in acute ischemic stroke patients undergoing endovascular thrombectomy (EVT). METHODS: This prospective single-center cohort trial enrolled patients with successful recanalization (defined as a score on the expanded Thrombolysis In Cerebral Infarction (eTICI) scale of 2b to 3). Patients were classified into the EVT alone group and IA albumin group. The primary endpoint was any intracranial hemorrhage (ICH). Secondary endpoints included pulmonary edema/congestive heart failure, symptomatic ICH, and all-cause mortality within 90 days. Exploratory efficacy endpoints included excellent outcome at 90 days (defined as a modified Rankin Scale score of 0-1), final infarct volume, and glymphatic system activity quantified by diffusion tensor imaging via the ALPS (analysis along the perivascular space) index. RESULTS: We enrolled 251 patients, with 103 in the IA albumin group and 148 in the EVT alone group. After propensity score matching, each group had 103 patients with balanced baseline characteristics. The primary safety outcome of any ICH occurred in 16.5% of the albumin group versus 25.2% of controls, with no statistically significant difference between groups (OR 0.25, 95% CI 0.25 to 1.09, P=0.081). No significant differences were observed in other safety outcomes. In the post hoc exploratory efficacy analyses, the IA albumin group had a greater likelihood of excellent neurological outcome at 90 days, smaller final infarct volumes, and higher ALPS index. CONCLUSION: In patients with acute large vessel occlusion, adjunctive IA albumin after successful thrombectomy was safe and well-tolerated. In post hoc exploratory analyses, this treatment was associated with a higher likelihood of achieving an excellent neurological outcome at 90 days and with reduced final infarct volume. The neuroprotective effect may be mediated by restoration of glymphatic function. These promising findings warrant validation in multicenter randomized trials.