Introduction

Recent landmark randomized controlled trial data1–7 have initiated a global transformational change in acute stroke therapy for ischemic stroke patients with large vessel occlusion. With endovascular thrombectomy established as the new standard of care for patients with large vessel occlusions, increased attention has turned towards service delivery to as many eligible patients as possible. The SNIS, in concert with other regional, national and international societies, has focused on this agenda.8 9 As both the need for and availability of endovascular thrombectomy grows, the terminology describing eligible patients requires uniformity. An operational definition of the clinical scenario in which a stroke patient has an urgent need for endovascular thrombectomy becomes increasingly important.10 11 A standardized nomenclature that uses consistently defined terms will facilitate continuous quality improvement as the field grows and understanding is advanced.12

Endovascular thrombectomy is a therapy specifically directed towards proximal cerebral vascular occlusions. Earlier studies with equivocal results for the benefit of this therapy13–15 were noteworthy for the absence of confirmation of pre-procedure vascular status. Recent positive trials were characterized by the requirement that vascular occlusion be documented as a requisite for patient enrollment in the trials.1–7 However, across these recent landmark trials there was significant variability in the definition of large vessel …