A 65-year-old hypertensive black man presented to the emergency department with onset of right face, arm, and hand paralysis, and difficulty communicating. Rapid diagnostic testing using MRI revealed an ischemic infarct in the left middle cerebral artery (Figure 230-1). He was evaluated by a stroke response team and was found to be a candidate for tissue plasminogen activator (TPA). After the stroke, he was treated with aspirin, antihypertensives, and cholesterol-lowering medication. He recovered 80% of his neurologic deficit over the next 3 months. Figure 230-2 is a noncontrast CT image of this patient 2 weeks later.
Acute left middle cerebral artery infarct on MRI of a 65-year-old hypertensive man. The MRI demonstrates increased signal intensity (arrows). Abnormalities in MRI occur before those seen on CT during ischemic strokes. (Courtesy of Chen MYM, Pope TL, Ott DJ. Basic Radiology. New York, NY: McGraw-Hill; 2004:338.)
Noncontrast CT image of a subacute left middle cerebral artery infarct (arrows). This was done 2 weeks after the stroke in the same patient as previous figure. CT findings occur later than MRI findings in ischemic strokes. (Courtesy of Chen MYM, Pope TL, Ott DJ. Basic Radiology. New York, NY: McGraw-Hill; 2004:338.)
Cerebral vascular accidents or strokes are common, especially in older populations. Most strokes are ischemic or hemorrhagic. Risk factors include hypertension, smoking, diabetes mellitus, and atrial fibrillation. Thirty-day mortality for a first stroke is greater than 20%.
- Cerebral vascular accidents (CVAs) affect approximately 700,000 people per year in the United States, most being older than age 65 years.1
- Ischemic (66%) and hemorrhagic (10%) strokes account for most strokes.1
- Prevalence of stroke and mortality are higher in blacks than in whites. Prevalence is 753 versus 424 per 100,000 and mortality is 95.8 versus 73.7 per 100,000 for black and white men, respectively.1
- CVAs are typically classified into cardioembolic (15% to 22%), large vessel (10% to 12%), small vessel (15% to 18%), other known cause (2% to 4%), and undetermined cause (46% to 51%).2
- Ischemic CVAs occur when atherosclerosis progresses to a plaque, which ruptures acutely. Each step of this process is mediated by inflammation.3
- Hemorrhagic CVAs occur when vessels bleed into the brain, usually as the result of elevated blood pressure.
- Other known causes of CVAs include inflammatory disorders (giant cell arteritis, systemic lupus erythematosus [SLE], polyarteritis nodosa, granulomatous angiitis, syphilis, and AIDS), fibromuscular dysplasia, drugs (cocaine, amphetamines, and heroin), hematologic disorders (thrombocytopenia, polycythemia, and sickle cell), and hypercoagulable states.
- Hypertension (HTN)—The predominant risk factor for more than 50% of all strokes. Prehypertension (blood pressure in the range of 130 to 139/85 to 89) carries ...