Influence of the number of passes of Stent-Retriever on the occurrence of parenchymal hematomas in stroke patients undergoing thrombectomy

Abstract

Introduction: Mechanical thrombectomy (MT) is the mainstay of treatment for major artery occlusion in stroke patients. It is not known whether there is a limit to the number of passes after which is no longer effective and becomes counterproductive. Parenchymal hematoma (PH) is a serious complication in these patients with unclear underlying mechanisms. We have examined whether the number of passes correlates with a significant increase in PH.Methods: We retrospectively analyzed the impact of the number of passes on patients treated between January 2017 and April 2020 in our centre. The main objective was to assess the correlation of the number of passes with the percentage of PH assessed by CT 24 h after endovascular treatment. Successful recanalization was defined as TICIm 2b-3. A good clinical outcome was defined as 90-day mRS 6 passes was still 31.25%. > 3 passes had a significantly higher incidence of PH (p = 0.026). In a multivariate analysis, the ASPECTS scale, the number of passes, and arterial puncture to recanalization time, were independent predictors related to PH. Of the 18 parenchymal hematomas, 5 occurred in patients with > 6 passes. Conclusions: The increase in PH risk for patients undergoing > 3 passes becomes significant when > 6 passes are performed. At this point it is important to ponder the risk of parenchymal hematoma and a possible negative treatment outcome.