Experimental Evaluation of the Effectiveness of Aspiration-Based Techniques to Treat Different Types of Acute Thromboembolic Occlusions in the Femoropopliteal Vascular System Using an In Vitro Flow Model

Schekeb Aludin,René Rusch,Philipp Jost Schäfer,Christoph Borzikowsky,Julian Pfarr,Rouven Berndt,Jens Trentmann,Olav Jansen

doi:10.1007/s00270-021-03024-8

Abstract

PurposeIn this in vitro study, the effectiveness and safety of four aspiration-based techniques for thrombectomy are evaluated for three types of thrombi in a flow model simulating the femoropopliteal segment.Material and MethodsRed, white, and mixed thrombi were produced in a standardized manner and used to simulate occlusion of a superficial femoral artery using a pulsatile flow model. Four techniques were compared: aspiration alone, aspiration + stent retriever, exposing thrombus to laser by an excimer laser system and a laser catheter + aspiration, and aspiration + mechanical fragmentation by a separator. Rate of first-pass recanalization, embolic events, and number of embolized fragments > 1 mm were compared.ResultsAspiration alone, stent retriever, laser, and separator differed in rates of first-pass recanalization (53.3%; 86.6%; 20%; and 100%) and embolic events (40%; 93.3%; 73.3%; and 60%). Number of embolized fragments was lowest with aspiration and higher with separator, laser, and stent retriever. Rates of first-pass-recanalization (75%; 75%; and 45%) and embolic events (65%; 60%; and 75%) differed for red, white, and mixed thrombi. The mixed thrombus caused the highest number of embolized fragments, which was particularly high using the stent retriever.ConclusionAdditional use of mechanical techniques significantly enhances the effectiveness of thrombectomy but simultaneously provokes more embolism. Laser seems to negatively alter the structure of a thrombus and thus diminishes the effectiveness, while provoking embolism. All techniques had lowest effectiveness, but highest embolism with the mixed thrombus. This was particularly striking when a stent retriever was used with the mixed thrombus.

Highlights

Aspiration alone, stent retriever, laser, and separator differed in rates of first-pass recanalization (53.3%; 86.6%; 20%; and 100%) and embolic events (40%; 93.3%; 73.3%; and 60%)
Number of embolized fragments was lowest with aspiration and higher with separator, laser, and stent retriever
Rates of first-pass-recanalization (75%; 75%; and 45%) and embolic events (65%; 60%; and 75%) differed for red, white, and mixed thrombi

Summary

Introduction

Percutaneous thrombectomy is an important option for endovascular treatment of acute limb ischemia (ALI). One of the oldest techniques here is percutaneous aspiration thrombectomy (PAT), which became the standard endovascular treatment of ALI [1,2,3,4]. Cardiointerventional field [8,9,10] As these techniques prove high effectiveness, they were partly attempted in peripheral vessels, too [11,12,13]. Red thrombi form quickly under static circumstances and are rich in erythrocytes. They are more likely in venous thrombosis but can appear in arteries. Several studies examined thrombi extracted from patients with AIS and acute coronary syndrome (ACS), indicating such heterogeneous composition [19,20,21,22]. This aspect seems to play a relevant role in peripheral thrombectomy, too

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Discussion

Conclusion