Choosing the Best Catheter for Aspiration Hemodynamics in AIS Treatment

Introduction 8F catheters serve as conduits to provide stable access and support for delivery of smaller 6F aspiration catheters (ACs) to intracranial vessel occlusions in AIS treatment. Recent advancements in catheter technology have led to the generation of superbore catheters (SBCs) (ID>0.088″). Designed to be placed in the MCA, SBCs can be used for direct contact aspiration but also to deliver 6F ACs intracranially. SBC's offer potential for better recanalization via their distal placement and enhanced control of local blood pressure and flow, compared to balloon guide catheter (BGC) and regular guide catheter (GC) systems, which are usually placed in the ICA offering proximal but more limited distal haemodynamic control. Purpose To objectively assess different conduit catheter technologies in terms of deliverability, local impact on blood pressure and flow, and clot retrieval success in vitro. Methods Two in vitro anatomical models were used. Two SBCs, CEREGLIDE 92 (J&J MedTech Neurovascular) and TracStar/Zoom 88 (Imperative Care), and one BGC system, EMBOGUARD (J&J MedTech Neurovascular), were used together with 0.071″ ACs. In addition, one GC, Neuron MAX (Penumbra), was evaluated with two different 6F ACs; RED68 (Penumbra) and SOFIA (Terumo Neuro). Two types of thrombus analogues, cohesive and friable, were used to create an occlusion in the M1‐segment of the MCA. Device tracking and clot retrieval were evaluated by two experienced neurointerventionalists. Physiological blood pressure and flow were simulated and monitored throughout the experiment. Results Positioning of SBCs in the MCA resulted in a significant reduction of local blood pressure and flow in comparison to GC systems positioned in the proximal ICA (p<0.001). However, when the SBC could not reach the MCA, they displayed similar haemodynamic control as the GC systems. A complete configuration of the Circle of Willis (CoW) limited the effectiveness of proximal ICA flow arrest via the BGC to reduce antegrade flow to the MCA (p<0.001). SBC systems positioned in the M1 had the highest rates of retrieval success for friable thrombi, presumably as flow reversal in the MCA was achieved during aspiration (p<0.001). Cohesive clot retrieval was more sensitive to clot interactions with the catheter tip. The Zoom 88 SBC system had lower rates of retrieval success due to difficulties in tracking and poor alignment of the clot with the catheter bevelled tip. Conclusion Clot retrieval success is influenced by the location of the conduit for the 6F aspiration catheter and the design of the aspiration catheter tip.