Mechanical Thrombectomy for Acute Ischemic Stroke in a Low-volume Stroke Center: Comparison of Workflow Times and Recanalization Rate among Three Devices

Abstract

© 2016 The Editorial Committee of Journal of Neuroendovascular Therapy. All rights reserved. Objectives: Mechanical thrombectomy for acute ischemic stroke needs to be performed in the shortest possible workflow time and have a high recanalization rate. The steep learning curve for this procedure is essential for comprehensive as well as low-volume stroke centers, wherein the annual number of mechanical thrombectomy cases is less than 10. We retrospectively evaluated the workflow times and successful recanalization rates of three types of devices for mechanical thrombectomy: the Merci retriever, the Penumbra System, and the stent retriever. We concomitantly assessed the learning curves for each device in this procedure. Methods: We retrospectively reviewed 19 patients who were transferred to our stroke center and underwent mechanical thrombectomy between February 2012 and August 2014. Time intervals between the placement of a guiding catheter and recanalization or final angiography (guide to revascularization time; GRT) were calculated from time-stamped images during the procedure. Results: Three cases were treated with the Merci retriever, 11 with the Penumbra system, and five with the stent retriever. There was a significantly higher successful recanalization rate [as indicated by the Thrombolysis in Cerebral Infarction (TICI) scale grade 2B or 3] between the three devices (0% in the Merci retriever group, 36.3% in the Penumbra system group, and 100% in the stent retriever group; p = 0.009). The median GRT was 66, 81, and 22 min for the Merci retriever, the Penumbra system, and the stent retriever, respectively; a statistically significant difference was noted between these groups (p = 0.016). Conclusions: The use of the stent retriever in mechanical thrombectomy for acute ischemic stroke seems suitable in low-volume stroke centers given its high success rate and ease of use.