Mechanical thrombectomy failure in anterior circulation large vessel occlusion: an overview from the ROSSETTI registry.

BACKGROUND: Although mechanical thrombectomy (MT) is an effective treatment for large vessel occlusion (LVO) with a high successful recanalization rate, MT failure (MTF) occurs in 10-15% of cases and is associated with unfavorable outcomes. However, little is known about the clinical, technical, and radiological reasons for MTF. We investigated the technical factors associated with MTF.

METHODS: We conducted a retrospective analysis of consecutive patients with anterior LVO prospectively included in the ongoing observational multicenter ROSSETTI registry. Patients were categorized according to the success (≥mTICI 2b) or failure (<mTICI 2b) of the MT procedure. Baseline clinical and demographic characteristics, endovascular MT techniques, and angiographic and clinical outcomes were compared. Multivariate analysis for prediction of MTF was performed.

RESULTS: We analyzed 4135 patients, including 325 patients (7.9%) with MTF. Patients in the MTF group had a significantly lower Alberta Stroke Program Early CT Score (ASPECTS) at baseline (8 (7-10) vs 9 (8-10)), longer time since last time seen well (279 min vs 262 min), increased MT procedure time (76 min vs 31 min), higher rate of complications (23% vs 4%), higher symptomatic intracerebral hemorrhage (21% vs 7.9%), higher 24 hour National Institutes of Health Stroke Scale score (19 vs 6), worse functional outcome at 3 months (modified Rankin Scale score 0-2, 15.6% vs 53%), and higher mortality (45% vs 20%). Four or more passes were an independent predictor of MTF (OR 3.46, 95% CI 2.58 to 4.63; P<0.001). None of the endovascular techniques demonstrated a higher likelihood of MTF.

CONCLUSION: In this study, MTF in anterior circulation LVO was associated with a high complication rate and worse outcomes.