Clinical outcomes of endovascular treatment in patients with M2 segment occlusion of the middle cerebral artery of different etiologies: A retrospective study

Abstract Background Distal medium vessel occlusion may lead to severe neurological deficits. The aim of this study was to investigate the differences in endovascular treatment (EVT) procedure and their impact on clinical outcomes in patients with different etiologies of the M2 segment of the middle cerebral artery (M2-MCA) occlusion. Methods We conducted a retrospective analysis of patients with M2-MCA occlusion treated with endovascular treatment at Army Medical Center from January 2015 to July 2023. Patients were divided into atherosclerosis group and embolization group, and we determined the etiology of stroke based on the imaging features during EVT. Procedure-related outcomes included recanalization rates, treatment modalities, and procedural complications. Clinical outcomes included the good outcome (modified Rankin Scale score 0–2) at 90 days, incidence of symptomatic intracranial hemorrhage (sICH) and any intracranial hemorrhage within 24 hours, and mortality at 90 days. Results A total of 81 patients were included in the analysis, and the numbers of patients in the atherosclerosis and embolization groups were 20 and 61, respectively. Patients in the embolization group treated with more number of mechanical thrombectomy (2 1–3 vs 1 1–2, P = 0.028). However, the total number of EVT (2.5 1–4 vs 2 1–3, P = 0.036) and the proportion of patients treated with rescue therapy (50.0% vs 1.6%, P<0.001) were significantly greater in the atherosclerosis group. The recanalization rate and incidence of procedural complications were not significantly different between the two groups. The good outcome at 90 days, incidence of sICH and any intracranial hemorrhage within 24 hours, and mortality at 90 days were also no statistical difference between the two groups. Conclusion For patients with M2-MCA occlusion of different etiologies, neurointerventionalists may choose different EVT modalities. There were no significant differences in recanalization rates, procedural complications, or clinical outcomes.