DAWN and DEFUSE-3 trials: is time still important?

Background Endovascular thrombectomy has been proven effective in the first 6 h after onset of stroke and large-vessel occlusion in the anterior cerebral circulation. To date, it was not clear whether thrombectomy beyond 6 h is also beneficial. Methods A summary of the prospective DAWN (DWI or CTP Assessment with Clinical Mismatch in the Triage of Wake-Up and Late Presenting Strokes Undergoing Neurointervention with Trevo) and DEFUSE-3 (Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke) trials is presented. Results The DAWN and DEFUSE-3 trials showed the efficacy of thrombectomy in selected patients with occlusion of proximal vessels in the anterior circulation up to 24 h after suspected onset of symptoms. Conclusion Thrombectomy was shown to have high efficacy up to 24 h after suspected symptom onset; however, patient selection is very complex. Early detection of large-vessel occlusion is of utmost importance. The cooperation between existing neurovascular networks should be adapted according to these new findings.