Acute ischaemic stroke: part II. The vertebrobasilar circulation.

OBJECTIVE To review recent advances in the management of acute ischaemic stroke in a two part presentation. DATA SOURCES Articles and a review of studies reported from 1990 to 2000 and identified through a MEDLINE search of the English language literature on acute ischaemic stroke. SUMMARY OF REVIEW An acute ischaemic stroke of the vertebrobasilar circulation is investigated initially with a cerebral computed tomography scan largely to differentiate it from a haemorrhagic stroke. However, cerebral magnetic resonance imaging identifies the ischaemic brainstem lesions more accurately and is often performed with MR angiography to determine the site and extent of the ischaemic vertebrobasilar lesion. Treatment with aspirin (150-300 mg) within the first 48 hr as well as management in a specialised unit focusing on resuscitation and prevention of complications has reduced morbidity and mortality. While therapy to improve cerebral blood flow or agents to reduce further neuronal damage have not produced consistent improvement in outcome, numerous small studies using intravenous or intraarterial thrombolytics, percutaneous transluminal angioplasty or stents have reported improved outcome in selected cases. CONCLUSIONS An acute ischaemic stroke in the distribution of the vertebrobasilar circulation requires aspirin 150-300 mg daily and management in an acute stroke unit. Intra-arterial or intravenous thrombolytic therapy and percutaneous transluminal angioplasty or stents to improve cerebral blood flow (even up to 24 hours after the event) have been reported to be beneficial in selected cases.