TENSION (Efficacy and safety of ThrombEctomy iN Stroke with extended leSION and extended time window: a randomized, controlled trial) strives at providing innovative treatment to patients with severe stroke to reduce the individual and societal burden of death and dependency from stroke. To this end, TENSION is a randomized, controlled, prospective, open label, blinded endpoint (PROBE) trial of thrombectomy in stroke patients with extended ischemic stroke lesions and patients presenting in a late time window, who are currently excluded from available effective treatment approaches.