Mechanical thrombectomy in distal residual occlusions of the middle cerebral artery after large vessel recanalization in acute stroke: 2b or not 2b? A pragmatic approach in real-life scenarios.

Abstract: BACKGROUND AND PURPOSE: Recent studies have suggested that a recanalization grade of modified thrombolysis in cerebral infarction (mTICI) ≥2c is strongly related with good clinical outcome rather than the current therapeutic angiography target ≥2b. In order to achieve better recanalization, additional further maneuvers on distal residual vessel occlusion may be required. The aim of this paper was to evaluate the safety and efficacy of rescue treatment in residual vessel occlusions (RVOs) after recanalization of large vessel occlusions in the anterior circulation. METHODS A single-center retrospective review of a prospectively maintained stroke databank was performed. Patients presenting with RVOs after mechanical thrombectomy on M1/ICA terminus were included and further divided into “treated” and “untreated” groups: the former underwent additional maneuvers on RVOs while the latter did not. Baseline and post-treatment clinical, radiologic, and angiographic data were compared between the two groups. Endpoints included good functional outcome (mRS≤2) rates of hemorrhagic transformations, neurologic deterioration and mortality. RESULTS RVOs were observed in 183/488 patients (37,5%). 74/183 (40.4%) underwent rescue treatment showing a better outcome in terms of median 24h-NIHSS (13 vs 18, p CONCLUSIONS When feasible, improving mTICI2a-2b recanalization to mTICI2c/3 is safe and associated with a better clinical outcome, particularly for residual occlusions involving the superior branch of bifurcation.