Risk Factors and Clinical Outcomes of Arterial Re-Occlusion After Successful Mechanical Thrombectomy for Emergent Intracranial Large Vessel Occlusion.

Re-occlusion of initially recanalized arteries after thrombectomy is a significant concern that may lead to poor outcomes. This study aimed to identify the risk factors and evaluate the prognosis of arterial re-occlusion following successful thrombectomy in patients diagnosed with emergent large-vessel occlusion (ELVO). We retrospectively analyzed data from 155 consecutive patients with ELVO who underwent mechanical thrombectomy (MT). Patients were classified into two groups according to whether the initial recanalized artery was re-occluded within 7 days after successful thrombectomy: re-occlusion and non-occlusion groups. Multivariate analysis was performed for potentially associated variables with < 0.20 in the univariate analysis to identify the independent risk factors of re-occlusion. Differences in clinical outcomes were also assessed in these two groups. Re-occlusion occurred in 10.3% of patients (16/155). Multivariate analysis demonstrated that large artery atherosclerosis (odds ratio [OR]: 3.942, 95% confidence interval [CI]: 1.247-12.464; = 0.020), the number of device passes (OR: 2.509, 95% CI: 1.352-4.654; = 0.004), and residual thrombus/stenosis (OR: 4.123, 95% CI: 1.267-13.415; = 0.019) were independently associated with re-occlusion. Patients with re-occlusion had significantly worse NIHSS scores at discharge and lower opportunities for achieving functional independence at 3 months after MT than patients without re-occlusion. Large artery atherosclerosis, a high number of thrombectomy device passes, and residual thrombus/stenosis seemed to promote re-occlusion after successful recanalization. Timely identification and proper treatment strategies to prevent re-occlusion are warranted to improve clinical outcomes, especially among high-risk patients.