Thrombus migration in patients with acute ischaemic stroke undergoing endovascular thrombectomy.

Objective: The impact of thrombus migration (TM) prior to endovascular thrombectomy (EVT) on clinical outcomes and revascularisation rates remains unknown. We aimed to examine whether preinterventional TM modifies the treatment effects of direct EVT versus bridging EVT in acute large vessel occlusion patients.

Methods: All patients undergoing catheter angiography in the Direct Intra-arterial thrombectomy in order to Revascularise acute ischaemic stroke patients with large vessel occlusion Efficiently in Chinese Tertiary hospitals: A Multicentre randomised clinical Trial were included. TM was determined by radiologists unaware of the study by analysing discrepancies between computed tomographic angiography at baseline and first-run digital subtraction angiography before EVT. The primary outcome was the score on the modified Rankin scale (mRS) assessed at 90 days.

Results: Of 627 included patients, the TM rate was 11.3% (71/627). In the multivariable logistic regression model, baseline National Institutes of Health Stroke Scale score (adjusted OR 0.956, 95% CI 0.916 to 0.999; p=0.043) and intravenous thrombolysis (adjusted OR 2.614, 95% CI 1.514 to 4.514; p<0.001) were independently associated with TM. The patients with TM were less likely to be completely recanalised than those without TM (21.27% vs 36.23%, p=0.040). The interaction of TM and the EVT treatment effect did not significantly affect mRS shift analysis (p=0.687) or mRS scores of 0 to 1 (p=0.436).

Conclusion: Preinterventional TM does not modify the treatment effects of direct versus bridging EVT on functional outcomes in patients with acute ischaemic stroke with anterior large vessel occlusion. TM leads to a lower complete recanalisation rate.