How are stroke and transient ischemic attack differentiated?
Who is eligible for IV recombinant tissue plasminogen activator?
What is the best cerebral imaging modality?
What is the optimal blood pressure in hospitalized patients with stroke?
What is the best antiplatelet therapy for secondary prevention of transient ischemic attack and stroke?
Should every patient be started on a statin?
Stroke is the third leading cause of death in the United States. There are more than 700,000 strokes in the United States each year, resulting in more than 160,000 deaths annually, with 4.8 million stroke survivors alive today. Although there was a 60% decline in stroke mortality between 1968 and 1996, the rate of decline began to slow in the 1990s and has plateaued in several regions of the country. The incidence of stroke may actually be increasing. From 1988 to 1997, the age-adjusted hospitalization rate for stroke grew by 19%, and total stroke hospitalizations increased by 39%. In 2004, the cost of stroke in the United States was estimated at $53.6 billion (direct and indirect costs), with a mean lifetime cost estimated at $140,048. Stroke is also a leading cause of functional impairments, with 20% of survivors requiring institutional care after 3 months, and 15% to 30% being permanently disabled. Utility analyses show that a major stroke is viewed by more than half of those at risk as being worse than death.
The most common cause of stroke is atherosclerosis of large and medium-size vessels of the neck and base of the brain (Figure 210-1). Risk factors for atherosclerosis include hypertension, diabetes, hyperlipidemia, cigarette smoking, and family history. Hypertension and diabetes also predispose to lacunae, which result from blockage of small perforating branches of the large cerebral arteries, with a predilection for the basal ganglia, thalamus, internal capsule, and pons. Patients with giant cell arteritis, systemic lupus erythematosus, and other vasculitides are at increased risk of stroke. Fibromuscular dysplasia is a cause of stroke in younger patients and is more common in women. Atrial fibrillation and valvular heart disease predispose to embolic stroke. Cocaine use predisposes to stroke for several reasons, including vasospasm, activating effects on platelets, and rupture of arteriovenous malformations and aneursyms in association with hypertension. IV drug users may develop embolic stroke from bacterial endocarditis. Stroke may also result from dissection of the carotid and/or vertebral arteries. Moyamoya syndrome results from bilateral narrowing of the distal internal carotids and adjacent anterior and middle cerebral arteries, with the development of fragile collateral vessels on angiography (Figure 210-2). It may be inherited as an autosomal recessive disorder or acquired in the setting of atherosclerosis, sickle cell disease, or basilar meningitis. Children present with ischemic stroke, whereas adults tend to develop intracranial hemorrhage. Hypercoagulability from genetic abnormalities in coagulation factors, leukemia, myeloproliferative disorders, antiphospholipid antibody syndrome, oral contraceptives, and sickle cell disease also predispose to stroke. Causes of stroke are summarized in Table 210-1.