Ischemic stroke represents the fifth most common cause of death in the western world and the number one cause of long-term disability. Until recent times, systemic intravenous fibrinolysis was the only evidence-based therapy for patients with acute onset of stroke due to large vessel occlusion.
History The world's first thrombectomy (in case of blood clot in the brain) was performed in 1994 at Sahlgrenska University Hospital, Gothenburg, Sweden by senior physician
Gunnar Wikholm. In 2015, the results of five trials from different countries were published in the
New England Journal of Medicine, demonstrating the safety and efficacy of mechanical thrombectomy with stent-retrievers in improving outcomes and reducing mortality for patients who present within six hours from their time last known well. It is now a widespread procedure performed in many hospitals around the globe, especially comprehensive stroke centers, although many other hospitals are not yet able to supply the service enough to meet the need. Large obstacles to making EVT more widely available are both systematic hurdles at the prehospital stages Most studies, however, have focused on thrombectomies in anterior circulation strokes. In recent years, increasing evidence on the efficacy of mechanical thrombectomy in posterior circulation strokes has been published.
Stent-retriever thrombectomy The procedure can be performed with general anesthesia or under conscious sedation in an angiographic room. A system of coaxial catheters is pushed inside the arterial circulation, usually through a percutaneous access to the right femoral artery. A microcatheter is finally positioned beyond the occluded segment and a stent-retriever is deployed to catch the thrombus; finally, the stent is pulled out from the artery, usually under continuous aspiration in the larger catheters.
Direct aspiration A different technique for mechanical thrombectomy in the brain is direct aspiration. It is performed by pushing a large soft aspiration catheter into the occluded vessel and applying direct aspiration to retrieve the thrombus; it can be combined with the stent-retriever technique to achieve higher recanalization rates, but the complexity of the procedure increases. Direct aspiration has not been studied as thoroughly as stent-retriever thrombectomy, but it is still widely performed because of its relative simplicity and low cost. ==Delivery==