Impact of thrombectomy techniques on outcome in medium or distal vessel occlusion: subanalysis of the DISTAL Trial.

Introduction
The optimal thrombectomy technique for medium/distal vessel occlusions (MDVOs) remains uncertain.Objective
To compare the safety and efficacy of aspiration thrombectomy (ADAPT) versus stent retriever thrombectomy (SR only) versus a primary combined approach (PCA).Patients And Methods
In this post hoc analysis of the DISTAL Trial, patients treated with first-line ADAPT, SR only, or PCA were included. The primary outcome was successful reperfusion (modified Thrombolysis in Cerebral Infarction 2b-3). Secondary outcomes included functional outcome (modified Rankin Scale score at 90 days) and intracranial hemorrhage. Statistical analysis was performed using mixed-effects logistic regression models.Results
Of 222 patients treated with thrombectomy, 36 underwent ADAPT, 37 SR only, and 149 a PCA as first-line strategy. The median number of thrombectomy passes was 1 (IQR 1-2). Final successful reperfusion was achieved in 76.5% with first-line ADAPT, in 61.1% with first-line SR only, and in 82.4% with first-line PCA. First pass successful reperfusion was achieved in 44.4% with ADAPT, 59.5% with SR only, and 66.4% with PCA. PCA was associated with higher first pass reperfusion rates compared with ADAPT (aOR=2.37, 95% CI 1.13 to 5.05, P=0.024). There were no significant differences in functional outcomes or safety endpoints among the techniques. ADAPT resulted in numerically more favorable functional outcome. PCA resulted in numerically higher numbers of symptomatic intracranial hemorrhage.Discussion And Conclusion
Final successful reperfusion rate after PCA was higher than after SR only. Functional and safety outcomes were not significantly different. Further research is warranted, including individual patient data meta-analyses and data on novel aspiration devices not used in this trial.