The Cutting Edge Technology Updates

A Novel Mechanical Thrombectomy Device to Improve TICI 3 First Pass Effect in Acute Ischemic Stroke

Complete reperfusion (TICI 3) after the first thrombectomy attempt or first-pass effect (FPE) is associated with the lowest mortality and best clinical outcomes in acute ischemic stroke (AIS). Although substantial technological advancements in endovascular therapy have been achieved since the initial studies in 2015, the TICI 3 FPE remains low at 24 to 30% (for retrievable stents or continuous uniform aspiration) with room for significant improvement.1 More recently, it has been suggested that near-complete reperfusion (TICI 2c) is associated with comparable good outcomes as TICI 3. However, a recent meta-analysis has shown that FPE inclusive of near-complete reperfusion (TICI 2c/3) is also low at 28% with existing mechanical thrombectomy devices.1 There is an unmet need for a new device to improve reperfusion efficiency. One such novel device, the CLEAR™ Aspiration System from Insera Therapeutics, Inc., aims to increase TICI 3 and TICI 2c/3 FPE, as it enables a proprietary cyclical or pulsatile vacuum aspiration technology to improve clot ingestion, reduce clot fragmentation), and improve the safety profile at the time of the procedure.1-3

Mohammed El-Ghanem
HCA Houston, Northwest Medical Center-Houston

The CLEAR Aspiration System is a digital vacuum aspiration system that allows neuro-interventionalists to employ uniform suction or cyclical suction patterns. The smart digital pump can be operated remotely via an iPad app (fig.1). Cyclical aspiration is performed using the PACE technique (a non-contact to contact aspiration).1 Insera Therapeutics has been awarded 72 issued or allowed patents to date in United States (U.S.) and outside U.S.

Emerging evidence shows that cyclical aspiration using the CLEAR Aspiration System increases first-pass recanalization, reduces emboli, and has an improved safety profile.1-3 The major clinical advantage of this device is it increases first-pass recanalization (with 50% more clot ingestion) and reduces clot fragmentation (with 8-fold reduction in distal emboli ≥200µ) compared to continuous uniform aspiration.3

Though currently not cleared to market in the U. S., Insera Therapeutics has received Conformité Européenne (CE) Mark approval for its flagship product, the CLEAR Aspiration System, which has been used to successfully treat patients (n=40) in the European Union

(fig.2 and fig.3).1 The recently published results of the CLEAR-1 study showed that cyclical aspiration using the CLEAR Aspiration System is safe and effective, achieves an exceedingly high rate of first-pass effect (TICI 3 FPE: 68.4%, and TICI 2c/3 FPE: 76.3%) for large-vessel strokes compared to stent retrievers and aspiration using continuous uniform aspiration (fig.2),1 with an approximately 80% rate of 90-day functional independence (mRS 0-2).1

1. Kalousek V, Yoo AJ, Sheth SA, Janardhan V, Mamic J, Janardhan V. “Cyclical aspiration using a novel mechanical thrombectomy device is associated with a high TICI 3 first pass effect in large-vessel strokes.” J Neuroimaging. 2021;1-12.

2. Kadirvel R, Dai D, Brinjikji W, Kallmes DF. “Cyclical aspiration has an improved safety profile compared to continuous uniform aspiration: In-vivo Randomized Study.” Presented at the 12th Annual Meeting of the Society of Vascular & Interventional Neurology held November 20-23, 2019 in Atlanta, Georgia. See link to the SVIN 2019 presentation.

3. Arslanian RA, Marosfoi M, Caroff J, King RM, Raskett C, Puri AS, Gounis MJ, Chueh J. “Complete clot ingestion with cyclical ADAPT increases first-pass recanalization and reduces distal embolization.” J Neurointervent Surg. 2019;11(9):931-936.