More than five stentriever passes: real benefit or futile recanalization?

Background and aims Clot extraction is associated with favorable outcome in patients with large vessel occlusions (LVO) undergoing endovascular thrombectomy (EVT). However, whether revascularization becomes futile or harmful with an increasing number of passes remains unknown. Methods We performed a retrospective analysis of 271 consecutive patients with LVO who underwent stentriever-based EVT as the primary recanalization strategy. Primary outcomes including favorable recanalization, survival, and favorable functional outcomes were compared according to a dichotomized number of stentriever passes utilized with a cutoff of 4. Results In the entire cohort, 234 (86%) patients reached favorable recanalization and 46 (17%) patients had ≥ 5 passes (range 5–40). Patients that had ≤ 4 passes had significantly higher rates of favorable recanalization and favorable outcomes and a trend towards lower mortality rates compared with those that had ≥ 5 stentriever passes (92% vs. 61%; p < 0.001, 52% vs. 30%; p = 0.009 and 12% vs. 22%, p = 0.098). Among patients that received ≥ 5 stentriever passes, 30% reached favorable outcomes. Patients who achieved recanalization after ≥ 5 passes had higher rates of favorable outcome in comparison with those who did not ( p = 0.009). Among patients that had ≥ 5 stentriever passes favorable recanalization (OR 97.3, 95%CI 2.8–3399.3) and admission NIHSS (OR 0.77, 95%CI 0.60–0.99) remained independent predictors of favorable outcome, whereas the number of passes did not. Conclusions A substantial proportion of patients reach favorable outcomes even when ≥ 5 stentriever passes are performed. Treatment choices should be individualized based on personal preferences and expertise as well as on patient and clot-specific characteristics.