EmboTrap (Neuravi/Johnson and Johnson’s Cerenovus) achieved a high reperfusion rate among acute ischaemic stroke patients with large vessel occlusion. With three, or fewer, passes of the device, 80.2% patients in the study achieved mTICI 2b–3 grade revascularisation in the target vessel. The results were presented at International Stroke Conference (ISC; 24–26 January 2018, Los Angeles, USA)
The ARISE II (Analysis of revascularisation in ischemic stroke with EmboTrap) study set out to assess the recanalisation efficacy and safety outcomes of the EmboTrap device in acute ischaemic stroke and to assess the functional outcomes 90 days after treatment.
Within three passes of the EmboTrap, high reperfusion was achieved among acute ischaemic stroke patients with large vessel occlusion (64.8% mTICI 2c–3, 80.2% mTICI 2b–3), the study primary endpoint. The final procedural vascularisation was 92.5% (mTICI 2b–3), with 50% of patients achieving excellent vascularisation (mTICI of 2c–3). The study showed successful reperfusion (mTICI 2b–3) in 51.5% of those treated with one pass of the EmboTrap, with 40.1% achieving excellent (mTICI 2c–3) reperfusion with one pass.
The newer generation of mechanical thrombectomy devices have significantly improved the outcomes of patients with acute ischaemic stroke but there are limitations. Currently, there is a failure to achieve successful reperfusion (mTICI≥2b) in around a third of the patients and there is a limited rate of complete, or near complete, reperfusion on a single pass, with the first pass effect being reported at 25–30%.
“The EmboTrap has a novel and unique design, with a view to addressing the shortcomings of other clot-retrieving devices. It has an inner channel that allows bypass while the device is open and five chambers to improve the clot-device interaction. This means that, theoretically, it is better able to grab the clot. The device also has a distal part with an extensive mesh to keep the clot in place, so that it does not fragment” said Osama Zaidat,MD, interventional neurologist and the principal investigator of the study.
The ARISE II study was an open label, single-arm, multicentre, prospective clinical study designed to obtain US FDA approval. The sample size was chosen based on results from SWIFT trial.
The group aimed to achieve a 68% success rate, which would announce the device as successful; as good as the current devices or even better. Angiograms were taken after each pass and these were adjudicated by an independent core lab at three different stages; after each pass, after three device passes and at the end of the procedure. This is the first time that angiograms have been independently adjudicated after the first pass. Using a different device prior to three passes was considered a failure, as was use of an aspiration pump with any device pass.
Two hundred and twenty eight people with large vessel occlusion were enrolled over 17 months at 19 sites (11 sites in the USA and eight in Europe). Of those, 227 were treated with EmboTrap. This number was chosen to allow for an attrition rate of 30%. Five patients were lost to follow-up.
“The treated patients had good outcomes. Just over 67% patients had functional independence (mRS 0–2) at 90 days follow-up, with 51.6% being highly functionally independent (mRS 0–1),” Zaidat said, adding, “What really matters to the patient and their family is that the patient returns to their previous functional ability and that happened in two-thirds of the patients. The safety outcome was excellent, only 5% had symptomatic haemorrhage or a device adverse event and the mortality at 90 days was 9%.”
