Choosing an Effective and Safe Direct Aspiration Setup for Tortuous Anatomy in Acute Ischemic Stroke: In vitro Study in a Physiological Flow Model

Abstract

Purpose A direct aspiration first pass technique (ADAPT) is an effective thrombectomy option in patients with acute ischemic stroke. Balloon guide catheters (BGC) seem to improve the efficacy of stent retrievers and ADAPT. The last generation 6F aspiration catheters require 9F BGCs, which are rigid devices that are challenging to position in a tortuous anatomy. In this experimental study the efficacy of 6F ADAPT alone and 5F ADAPT combined with 8F BGC was evaluated. Materials and Methods Either a fibrin rich (white) clot or an RBC rich (red) clot was placed in the M1 segment of a transparent silicon phantom. Physiological hemodynamic conditions were maintained. The clots were retrieved by 6F aspiration catheter via 8F long sheath or 5F aspiration catheter via a flexible 8F BGC. Thrombectomy was performed under direct visual control. The primary endpoints were the number of passes and the number of distal emboli. Results Ten experiments were made with each clot model and thrombectomy technique (n = 40). Full recanalization could be achieved in every experiment. First pass mTICI 3 could be achieved by 6F ADAPT in 80 % of red clots and 90 % of white clots. Distal emboli were caused in 10 % and 20 %, respectively. When using 5F ADAPT combined with BGC, a first pass mTICI 3 rate of 90 % in red clots and 100 % in white clots could be achieved. A 10 % rate of distal emboli occurred in both groups. In almost all experiments (both techniques), the thrombi clogged the aspiration catheter. No statistically significant differences could be found between the techniques and clot models. Conclusion 6F ADAPT without BGC was as effective as 5F ADAPT combined with a flexible 8F BGC, with both techniques showing high first-pass recanalization rates and low distal emboli rates. Especially in the case of a tortuous anatomy, these setups should be considered as alternatives to a rigid 9F BGC. The thrombus compositions seemed to be irrelevant in this setting. Key Points: Citation Format

In vitro and in silico modeling of endovascular stroke treatments for acute ischemic stroke

“…Of the studies with the focus on aspiration-only procedures, the ones performed by (Simon et al, 2014) and (Lally et al, 2016) examined the impact of different suction conditions. (Madjidyar et al, 2020) compared various aspiration procedures and devices in terms of flow characteristics, and the number of aspiration attempts and distal emboli. (Good et al, 2020) made use of an in vitro test model to validate the in silico model that they developed to investigate the effect of cyclic aspiration.…”

“…Other articles extend the models to include the A1 segment (Wenger et al, 2013), M1 and M2 divisions (Sanchez et al, 2020), M1-4 segments, anterior and posterior communicating arteries (Fennell et al, 2018), and the ophthalmic arteries (Girdhar et al, 2020). Others describe full Circle of Willis models (Chueh et al, 2020b;Maxim Mokin et al, 2015;Van Der Marel et al, 2016) or use a commercial model of the cerebrovasculature (Johnson et al, 2020a(Johnson et al, , 2020bMadjidyar et al, 2020Madjidyar et al, , 2015Tennuci et al, 2011). The majority of vascular models are tubular in design, apart from two studies where a hollowed-chamber was utilized (Good et al, 2020;Machi et al, 2017).…”

“…The middle cerebral artery (MCA) is the target vessel described in all articles, apart from where the M1 segment is specified (Fennell et al, 2018;Johnson et al, 2020aJohnson et al, , 2020bMadjidyar et al, 2020;Sanchez et al, 2020), or there is no target vessel identified (Giulia Machi et al, 2017;Ohshima et al, 2019;Simon et al, 2014;Weafer et al, 2019;Wenger et al, 2013). Overall, the range of geometries of the vascular models includes straight tubes (Fig.…”

“…Around half of the studies used idealized model geometries, some citing patient vessel dimensions from literature (Girdhar et al, 2020;Lally et al, 2016; Published manuscript at https://doi.org/10.1016/j.jbiomech.2021.110693 Machi et al, 2017;Ohshima et al, 2019;Sanchez et al, 2020;Simon et al, 2014;Tanyildizi et al, 2020;Tennuci et al, 2011;Wenger et al, 2013). The others used vascular models reconstructed from imaging data, where some utilized a commercial model developed from patient imaging data (Johnson et al, 2020a(Johnson et al, , 2020bMadjidyar et al, 2020Madjidyar et al, , 2015Tennuci et al, 2011), or designed their own model from brain Magnetic Resonance Angiography scans (Chueh et al, 2020b(Chueh et al, , 2012Van Der Marel et al, 2016), Computed Tomography Angiography scans (Maxim Mokin et al, 2015) or both Digital Subtraction Angiography and Computed Tomography Angiography scans (Fennell et al, 2018). One study used a chamber that represented an enlarged (5-times) cerebral artery (Good et al, 2020).…”

“…Six studies used two different thrombi to represent the extremes of hard and soft (Chueh et al, 2013(Chueh et al, , 2020bVan Der Marel et al, 2016), red and white (Machi et al, 2017) or fibrin-rich and RBC-rich clots (Madjidyar et al, 2020;Sanchez et al, 2020). (Weafer et al, 2019)…”