Catheter-Based Recanalization Techniques for Acute Ischemic Stroke

Most patients with acute ischemic stroke have thromboembolic material occluding large cerebral vessels, and hence disruption of cerebral blood flow [1–3]. If the arterial occlusion is relieved in a timely manner, a substantial reduction in the size and severity of the cerebral infarction can be achieved [4–7], with significant improvement in the level of disability among survivors [8]. For nearly a decade, the only recanalization strategy for acute ischemic stroke approved by the US Food and Drug Administration (FDA) was intravenous thrombolysis using tissue-type plasminogen activator (t-PA), alteplase (Genentech, San Francisco, California). Since its approval in 1995, t-PA has become a widely implemented strategy in the management of acute ischemic stroke, propelling the development of numerous primary stroke centers. The widespread clinical application of this strategy has confirmed its usefulness in a narrowly selected group of patients; the narrow selection criteria have, however, excluded most patients from receiving this therapy [9,10]. Widespread clinical use has also highlighted some of the serious limitations of intravenous t-PA that were originally observed in the clinical trials. Intravenous t-PA has only a limited role to play in the setting of a large thromboembolic burden, as seen in patients with acute occlusions of the internal carotid artery (ICA), proximal middle cerebral artery (MCA) [11], and basilar artery (BA). It works best in the