Current Status and Future Prospects of Intravenous tPA Thrombolysis and Mechanical Thrombectomy

Although current consensus is that intravenous tPA thrombolysis should be administered for ischemic stroke patients within 4.5 hours after onset, early recanalization is expected limitedly. On the other hand, for cases with large vessel occlusion (LVO) in anterior circulation within 4.5 hours after onset, mechanical thrombectomy (MT) is proved to be effective compared to medical treatment alone after five randomized controlled trials and meta-analysis. Moreover, in the treatment of cases even with 6 to 16 hours after onset, with perfusion images to identify ischemic penumbra and selecting candidates, it is also shown that MT is effective recently. However, so far, there is no evidence about MT for cases with relatively small vessel such as M2 branch of the middle cerebral artery or LVO in posterior circulation. In intravenous tPA thrombolysis and MT, the important point is that the shorter the time from onset to recanalization, the more cases with favorable outcome with modified Rankin Scale 0-2. Therefore, after patient admission to hospital, we should pay attention to the timeline such as Door to Picture, Door to Needle, Door to Puncture, and Puncture to Recanalization time, and shorten each time using stroke algorithm. Now, LVO in anterior circulation is disease with high possibility to recover by these intravenous tPA thrombolysis and MT. At the next stage, shortening Onset to Door time become more important. In the near future, we have to construct prehospital emergency system that can select adaptive cases appropriately and start to treat patients promptly.