The Endovascular Treatment of Acute Ischemic Stroke In properly selected patients who are not IV tPA candidates, intra-arterial thrombolysis and mechanical embolectomy are viable therapeutic options.

Before 1995, there were no proven or approved treatments for acute ischemic stroke (AIS); since then, intravenous (IV) tissue plasminogen activator (tPA), intra-arterial (IA) recombinant prourokinase (r-proUK), and mechanical embolectomy have all been shown to be effective in the treatment of AIS or clot removal from the brain. Furthermore, a wide variety of endovascular techniques and devices are currently under investigation, offering hope for the more than 750,000 strokes that occur in the US annually. 1 Despite these advances, there remain major obstacles to the widespread use of the available therapies. The major limitation is the fact that all therapies for AIS have a significant risk of intracerebral hemorrhage (ICH). This complication, the most feared complication of AIS therapy, has no effective treatment and is fatal nearly 80% of the time. Furthermore, the heterogeneous nature of AIS makes treatment decision making complex and requires a thorough knowledge of cerebral physiology, pathophysiology, anatomy, and medical management. 2 Patient selection is perhaps the most important factor in determining a good neurological outcome, and this requires extensive clinical experience in stroke treatment. PATHOPHYSIOLOGY Ischemic stroke has many possible causes including cardiac embolism (20%), extracranial atherosclerosis/thrombosis (10%‐12%), intracranial atherosclerosis (8%‐10%), lipohyalinosis (25%‐30%), aortic arch atherosclerosis (approximately 10%‐20%), dissection (<5%), and hypercoagulable states (<5%), among others. The composition of thrombi causing acute arterial occlusion can therefore be quite varied, and most often the underlying vasculature is normal (a major difference compared to the vessels of patients with acute coronary syndrome). These variables need to be taken into consideration when making acute treatment decisions.