P-001 Evaluation of cerebrovascular flow parameters relative to guide catheter position during acute ischemic stroke treatment

Abstract

<h3>Introduction/Purpose</h3> Studies show aspiration catheters with a high catheter-to-vessel ratio (catheter bore that closely matches the vessel diameter) achieve improved recanalization results. Additionally, higher rates of First Pass Effect result from proximal flow arrest using a balloon guide catheter (BGC). The purpose of this study is to quantify the effect of intracranial flow parameters using various catheter combinations for aspiration thrombectomy. <h3>Materials and Methods</h3> Using the Bioengineering Devices Laboratory benchtop flow model at Northern Arizona University, real-time flow and pressure measurements of catheter placement in the circle of Willis (CoW) model were recorded using various aspiration catheters placed at the middle cerebral artery (MCA) within guide catheters placed in the internal cerebral artery (ICA): Zoom 71 (Imperative Care, Z71) within Neuron MAX (Penumbra, NM), Z71 within Ballast (Balt, Ball), Z71 within Walrus (Q’APel Medical, W-BGC), React 68 (Medtronic, R68) within FlowGate2 (Stryker, F-BGC), and Zoom 88 (Imperative Care, Z88) alone in the MCA. The flow model consisted of a programmable, SuperPump AR (ViVitro Labs) that simulated physiological neurovascular flows and pressures. The benchtop accommodated swappable 3D-printed CoW models made from UV-cured acrylic-based co-polymers, with anatomical dimensions (Rai et.al., JNIS, 2013) and mechanical properties of human vessels (Norris et.al., JBMR 2021) (<b>figure 1-Top</b>). The flow model also incorporated a novel blood analog, matched to the viscosity and shear-thinning effect of blood, for simulating real-time pressure and flow measurements at each CoW branch. <h3>Results</h3> All catheter combinations resulted in significant flow reduction in the affected middle cerebral artery (MCA), with ~60% reduction using standard 8F guide catheters in the ICA and 6F aspiration catheters in the MCA. However, Z88 placement within the MCA for aspiration resulted in 96% flow reduction. A Z71 in the MCA, within a Z88 distal to the PComm (proximal to the carotid terminus), resulted in 80% flow reduction, similar to an R68 in the MCA within an inflated F-BGC in the proximal ICA. However, the inflated F-BGC also resulted in significantly larger flow reduction in the ipsilateral ACA (<b>figure 1 Bottom</b>). <h3>Conclusion</h3> Dramatically reduced MCA flow can significantly reduce downstream migration of thrombus during thrombectomy. This study demonstrates that Zoom 88 positioned distal to the PComm achieved similar rates of flow control as balloon guide catheters inflated in the proximal ICA. In all cases, flow compensation within the CoW affected the outflow rates of the ipsilateral and contralateral ACA branches, posterior cerebral arteries, and contralateral MCA. <h3>Disclosures</h3> <b>H. Berns:</b> 5; C; Northern Arizona University. <b>O. Fisher:</b> 5; C; Northern Arizona University. <b>B. Fennell:</b> 5; C; Northern Arizona University. <b>A. Ponugupaty:</b> 5; C; Northern Arizona University. <b>W. Merritt:</b> 4; C; Aneuvas Technologies, Inc.. 5; C; Northern Arizona University. <b>A. Ducruet:</b> 2; C; Medtronic, Stryker, Penumbra, Oculus, Koswire, Cerenovus. 4; C; Aneuvas Technologies, Inc.. 5; C; Barrow Neurological Institute. <b>T. Becker:</b> 4; C; Aneuvas Technologies, Inc.. 5; C; Northern Arizona University. 6; C; Imperative Care.