Clinical Implications of Preinterventional Thrombus Migration in Patients with Emergent Large Vessel Occlusion

Abstract

BACKGROUND: In patients treated with thrombectomy, thrombus migration (TM) to distal arterial segments is occasionally observed. We investigated the incidence of TM, factors associated with TM, and association between TM and clinical outcomes. METHODS: The study population consisted of 164 patients with anterior circulation stroke who underwent pretreatment brain computed tomography angiography and digital subtraction angiography before undergoing thrombectomy. TM was defined as a thrombus shift to a more distal arterial segment observed on digital subtraction angiography than that on computed tomography angiography. Successful and complete recanalization was defined as cerebral infarction perfusion scale scores of 2b-3 and 3, respectively. Good functional outcomes were defined as scores of <= 2 on the modified Rankin Scale at 3 months. The results are presented as adjusted odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Thirty-two patients (19.5%) had TM. Intravenous thrombolysis (IVT) (OR, 5.238; 95% CI, 1.653-16.603) and female sex (OR, 2.874; 95% CI, 1.135-7.277) were associated with TM. IVT-related TM was not significantly associated with thrombus inaccessibility (P = 0.304). In addition, TM was not associated with successful (P= 0.960) or complete (P = 0.612) recanalization. However, TM (OR, 2.777; 95% CI, 1.019-7.569), together with IVT (OR, 2.982; 95% CI, 1.332-6.676), a low National Institutes of Health Stroke Scale score OR, 0.906; 95% CI, 0.845-0.972), and successful recanalization (OR, 4.878; 95% CI, 1.940-12.266), were independently associated with good functional outcomes. CONCLUSIONS: TM is common, particularly after IVT. In addition, TM is associated with better functional outcomes, irrespective of the angiographic outcomes.