Pathogenesis, diagnosis, and treatment of hypertension-associated stroke.

Chronically elevated blood pressure predisposes to stroke through effects on the extracranial and intracranial cerebral vessels. Hypertension-associated disease of small-diameter penetrating cerebral arteries may produce either lacunar infarction or intracerebral hemorrhage. The role of hypertension in the pathogenesis of atherothromboembolic cerebral infarction must be questioned in view of the evidence that antihypertensive therapy does not prevent myocardial infarction. Hypertension, in the absence of rheumatic heart disease, is frequently associated with atrial fibrillation. The incidence of stroke due to embolization of thrombus from the fibrillating left atrium of the nonrheumatic heart may have been overestimated in the past. Ideally, investigation of the patient who has had a stroke should include a brain-imaging study and a cerebral arteriogram. In practice, however, arteriography cannot always be justified. Treatment of the completed stroke is unsatisfactory but tissue plaminogen activator and calcium-channel blockers hold promise for cerebral infarction. Surgical decompression of the posterior fossa can be life-saving in cases of cerebellar infarction or hemorrhage. In patients with cerebral infarction, aspirin has been shown to reduce the incidence of stroke recurrence.