Trevo versus Merci retrievers for thrombectomy revascularisation of large vessel occlusions in acute ischaemic stroke (TREVO 2): A randomised trial

Background Present mechanical devices are unable to achieve recanalisation in up to 20-40% of large vessel occlusion strokes. We compared effi cacy and safety of the Trevo Retriever, a new stent-like device, with its US Food and Drug Administration-cleared predecessor, the Merci Retriever. Methods In this open-label randomised controlled trial, we recruited patients at 26 sites in the USA and one in Spain. We included adults aged 18-85 years with angiographically confirmed large vessel occlusion strokes and US National Institutes of Health Stroke Scale (NIHSS) scores of 8-29 within 8 h of symptom onset. We randomly assigned patients (1:1) with sequentially numbered sealed envelopes to thrombectomy with Trevo or Merci devices. Randomisation was stratified by age (≤68 years vs 69-85 years) and NIHSS scores (≤18 vs 19-29) with alternating blocks of various sizes. The primary efficacy endpoint, assessed by an unmasked core laboratory, was thrombolysis in cerebral infarction (TICI) scores of 2 or greater reperfusion with the assigned device alone. The primary safety endpoint was a composite of procedure-related adverse events. Analyses were done by intention to treat.