Treatment outcomes of antegrade versus retrograde approaches in tandem occlusion: a single-center retrospective study from Vietnam.

Purpose: Tandem occlusion, characterized by concurrent extracranial and intracranial arterial occlusion, is associated with unfavorable clinical outcomes. Despite evidence from observational studies, multicenter registries, and meta-analyses comparing antegrade and retrograde endovascular approaches, the optimal treatment sequence remains unresolved. This study aimed to compare the clinical and angiographic outcomes of antegrade and retrograde strategies in patients with tandem occlusion in Vietnam. Method: A retrospective single-center study included 74 patients with tandem occlusion treated between January 2023 and June 2025 at Bach Mai Hospital, Hanoi. Patients were grouped into antegrade and retrograde treatment strategies. Demographic, clinical, imaging, and procedural characteristics were collected. The primary outcome was favorable functional outcome at 90 days [modified Rankin Scale (mRS) ≤ 2]. Secondary outcomes included successful reperfusion (mTICI ≥2b), early neurological improvement (NIHSS reduction ≥8 points), symptomatic intracerebral hemorrhage (sICH), and mortality. Result: The median age was 67 years (IQR 60.75-75), and 81.1% were male. Hypertension was present in 27/74 patients (36.5%). The predominant intracranial occlusion site was the M1 segment (63/74, 85.1%). The median groin puncture-to-reperfusion time was 53 min (IQR 39.75-85.25). Baseline NIHSS scores were similar between the two groups, and ASPECTS ≥6 was observed in 66 of 74 patients (89.2%). Successful reperfusion was achieved in 94.6% of the antegrade group and 91.9% of the retrograde group. Early stent occlusion occurred in 25.7% of patients, and delayed stent occlusion occurred in 4.1% of patients. Favorable functional outcome at 90 days occurred in 45.9% versus 40.5% ( Conclusion: No significant differences were observed between the two approaches in achieving successful reperfusion. Overall, the antegrade and retrograde strategies demonstrated comparable outcomes in reperfusion success, early neurological improvement, and 90-day functional recovery, with no clear clinical advantage for either technique. Accordingly, procedural selection may depend on operator preference and patient-specific anatomical factors. However, given the retrospective single-center design and limited sample size, further multicenter randomized controlled trials are needed to determine the optimal procedural sequence for tandem occlusions.