Stent Retriever Versus Contact Aspiration in Irregular Occlusion Phenotype

Summary

Patients with a clinico-neuroradiological mismatch pattern shown on the magnetic resonance imaging/Computed Tomography in the acute phase of stroke are more likely to benefit from reperfusion, are suitable candidates for endovascular therapy, and have a better clinical prognosis.

The ASTER Trial showed similar results between stent-retrievers and contact aspiration concerning the recanalization grade in anterior circulation occlusions. However, we still observe late and futile recanalizations, secondary either to extended ischemic lesions at baseline, long-time procedures or intraprocedural complications. The First Pass Effect that is the complete/nearly complete recanalization after the first maneuver, independently on the technique used, has been strongly associated with better clinical outcomes . In a recent paper we proposed a novel approach to identify those cases that could be treated with a specific technique (stent-retriever) with higher chances to achieve a complete or nearly complete recanalization, with lower procedure times and lower complication rates. This approach is focused on the identification of a regular or irregular phenotype of the occlusion site in patients with an M1-Middle Cerebral Artery occlusion. The phenotype is defined as "regular" whether the profile of the occlusion is abruptly cut without any irregularity and as "irregular" if any irregularity of the profile of the occlusion is observed. One of the hypotheses that could explain these results could be related to the composition of the clot : a soft and less organized clot could be more easily flattened by the pulsatile flow and therefore determine a regular aspect of the occlusion. A more solid and organized clot would, on the contrary, maintain an irregular profile because it would not be flattened by the blood flow and the contrast medium could highlight the irregularities of the proximal face of the clot.

The latter could be a favorable target for the use of a stent-retriever since the interaction between a solid clot and the struts of the stent could increase the chance to retrieve the clot. Therefore, we propose this randomized controlled trial to assess the superiority of stent-retrievers compared to contact aspiration in the treatment of irregular phenotype occlusions of the M1-Middle Cerebral Artery.

Conditions

• Stroke, Acute

Interventions

PROCEDURE

stent retriever thrombectomy

The technique used should be in accordance with the device IFU (instructions for use). A large bore access guide catheter possible is mandatory. A suitable delivery microcatheter is navigated over a microwire across the occlusion. A control superselective angiogram may be used to document the extent of occlusion and thrombus. The stent is left in place according to the internal practice of each participating center before the withdrawal. Any CE (european compliance)-marked stent retriever device is then deployed across the occlusion. A contact aspiration large bore catheter can be used in association with the stent retriever. A minimum of 3 attempts with Stent retriever should be performed. A revascularization score will be recorded after each device attempt.

PROCEDURE

contact aspiration thrombectomy

A 0.021 to 0.027 inch inner lumen microcatheter with a 0.014 to 0.016 inch microwire inside is then introduced into a large-bore aspiration catheter and this construct is introduced into the long sheath as a unit. A large bore balloon guide catheter has to be placed into the cervical internal carotid artery. The microcatheter is then advanced close to the thrombus and the large-bore aspiration catheter is advanced as close to the proximal aspect of the thrombus as possible. A control angiogram may be used to document the extent of occlusion and thrombus. After a 3 min waiting period, the large-bore aspiration catheter is connected to a continuous aspiration from the dedicated aspiration pump while simultaneously advancing the aspiration catheter up to the face of the thrombus. Once thrombus will be close to the aspiration catheter, then the system will carefully removed as a unit under continuous aspiration.

Sponsors & Collaborators

• Hopital Foch

  lead OTHER

Principal Investigators

• Arturo CONSOLI · Foch Hospital

• Bertrand LAPERGUE · Foch Hospital

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2022-12-19

Primary Completion

2025-02-01

Completion

2025-11-01

Countries

• France

Study Locations