脳梗塞Update：病態

抄録

According to the World Health Organization, about 15 million people suffer a stroke each year with roughly one–third resulting in death and another one–third sustaining severe permanent disability. Even in developed nations such as Japan, stroke is the third leading cause of death with more than 100,000 fatalities each year from approximately 3,000,000 stroke cases. Stroke can occur at any age but 75% of all strokes occur in people over the age of 65. Ischemic stroke, which accounts for about 70–80% of all strokes, is caused by an occlusion of a blood vessel by a blood clot stopping blood supply to a particular area of the brain. The effects of a stroke can be catastrophic because cessation of cerebral blood flow leads to energy failure and eventually cell death through necrosis as well as apoptosis, and triggers immune responses and inflammatory cell activation and infiltration. Recombinant tissue plasminogen activator (rtPA) can only be given within a narrow time window (4.5h) following stroke onset and carries the risk of inducing haemorrhage. Despite efforts to increase the use of such reperfusion therapies, only 4–5% of stroke patients receive intravenous thrombolysis. The worldwide percentage is even lower when developing nations are included. Among those who undergo reperfusion treatment, 25–30% have successful arterial recanalization. In addition, more recently introduced endovascular thrombectomy can achieve considerably higher recanalization rates approaching 90% in acute ischemic stroke patients. However, not all patients with recanalization have sustained clinical improvements, and not always is a treatment possible within the narrow time window required for thrombolysis and thrombectomy. Therefore, seeking effective treatment for stroke remains an urgent priority. To achieve success in developing more effective management of stroke, a better understanding of all aspects of stroke including prevention, diagnosis, treatment, and post–stroke recovery and complications is needed.