Abstract Number ‐ 37: A Clinical Multicenter Experience of Novel Tenzing Delivery Catheter for Thrombectomy in Acute Stroke
Authors: Bhattacharyya Meghna , Koneru Manisha , Shaikh Hamza , Patel Pratit , Thomas Ajith , Tonetti Daniel , Abdalkader Mohamad , Nguyen Thanh , Klein Piers , Hanel Ricardo A , Benalia Victor H , Cortez Gustavo M , Aghaebrahim Amin , Sauvageau Eric , Dmytriw Adam 
Published: April 2023

Introduction
Mechanical thrombectomy has become the standard of care to treat acute ischemic stroke patients with large vessel occlusions. Device performance and physician technique have developed since early trials proving the efficacy of the procedure1‐3. One of these techniques, direct aspiration first pass technique (ADAPT)4involves navigating a large‐bore catheter to the face of the clot and initiating suction. Navigating large‐bore catheters through intracranial neurovasculature has been accomplished using microcatheters and/or guidewires. Due to the large sizes of these aspiration catheters, the microcatheters used to help deliver the aspiration catheters into the brain form a “ledge” between the disparate lumens and prevent progression of the aspiration catheter into the distal neurovasculature and increase the risk of damaging arteries during advancement. A novel navigation support catheter, the Tenzing Delivery Catheter, has shown promising benchtop performance assisting large‐bore aspiration catheter delivery to the occlusion sitein vitro5. It demonstrated superior performance over traditional microcatheter/guidewire techniques in delivering the aspiration catheter to the occlusion in this model. While limited initial clinical experience from examining a small sample group appears to confirm this observation, a cumulative, large‐scale analysis of experience using the Tenzing catheter in clinical practice to further examine its safety, efficacy, and usability has not yet been performed. With that in mind, this study serves as an initial multicenter first‐experience investigation to assess the aforementioned factors and determine the utilization potential of Tenzing catheters.

Methods
This study was conducted via retrospective chart review across three institutions. Patients included in the study are 18 years old or older, underwent a thrombectomy procedure between January 1, 2020 and July 31, 2022, and whose procedures involved the use of the Tenzing delivery catheter system. Our primary outcome measures were success in delivering aspiration catheter, post treatment thrombus, and perioperative complications.

Results
In our sample size of n = 95, inclusive of patients from multiple institutions, it was found that in 96% of cases, the Tenzing catheter was successfully delivered to the occlusion site and successful reperfusion (mTICI less than or equal to 2b) was achieved in 90% of cases.In the majority of cases, the Tenzing delivery catheter was used to deliver an aspiration catheter to a middle cerebral artery occlusion (75%). Tenzing was advanced past the occlusion location (identified as the angiographic limit of contrast) in 59% of cases. Secondary emboli were observed 11% of the time. Other procedural complications were observed in 8% of patients while none was seen in 74%. On average, the median NIHSS decreased from 17 pre‐treatment to 10 post‐treatment.

Conclusions
Based on these findings, we conclude that the Tenzing Delivery Catheter is a safe and efficacious instrument in thrombectomy procedures. Given its high rate of revascularization and delivery success with few complications as demonstrated in this multicenter study.Future studies with larger patient volume are necessary to evaluate this important delivery catheter as it is used more frequently around the world.