Objective: This study aimed to investigate the association between the presence of the hyperdense middle cerebral artery sign (HMCAS) on pre-treatment non-contrast CT (NCCT) scans and the subsequent occurrence of poor functional outcomes and hemorrhagic transformation (HT) in patients with acute ischemic stroke due to large vessel occlusion (AIS-LVO) attributed to cardioembolic etiology, following mechanical thrombectomy (MT).
Methods: We conducted a retrospective analysis using patient data from the multicenter clinical trial known as MONFIS-ET, focusing on individuals with cardioembolic (CE) and large-artery atherosclerotic (LAA) occlusive strokes. Patients were categorized into four groups based on the presence of HMCAS and the underlying stroke etiology. We compared the 90-day modified Rankin score (mRS) and the incidence of HT between those with HMCAS and those without it, stratified by etiology.
Results: A total of 269 patients were included in the study, of which 85 (31.6%) exhibited HMCAS on NCCT scans. Patients without HMCAS demonstrated more favorable clinical outcomes compared to those with HMCAS (56.0% vs. 41.2%, p=0.024). Specifically, patients with HMCAS associated with cardioembolism (CE) had a less favorable outcome (20% vs. 46.7%, p=0.013) and a higher incidence of HT (65.7% vs. 33.3%, p=0.004). Conversely, there was no significant difference in prognosis between patients with HMCAS and those without it in the context of large artery atherosclerosis (58.2% vs. 57.7%, p=0.959). In multivariate logistic regression analysis, the HMCAS independently predicted poor prognosis in patients who underwent MT due to CE (OR: 4.054, 95% CI: 1.161-14.159, p=0.028).
Conclusion: In patients with AIS-LVO attributed to cardioembolic etiology who underwent MT, the presence of HMCAS on initial NCCT scans was found to be associated with an unfavorable outcome and a higher incidence of HT.
Clinical Trial Registration: ChiCTR 2300074368(retrospectively registered).