Hypertension and cerebrovascular disease

Arterial hypertension plays a major part in stroke because it is a well-documented risk factor for stroke, it is common, and it can be treated effectively. Arterial hypertension leads to cerebrovascular disease through multiple mechanisms. Chronic hypertension accelerates cerebral vasculopathy in arteries of all sizes. These pathologic changes increase the risk of both ischemic and hemorrhagic stroke 2.7 times that in normotensive individuals. Hypertension also leads to ischemic heart disease, which in turn increases the risk of cardioembolic stroke. Effective treatment of chronic hypertension reduces the incidence of stroke 35% and has a large impact on health care statistics because of the prevalence of hypertension. Acute elevation of blood pressure above the level of cerebral blood flow autoregulation produces hypertensive encephalopathy. If recognized and treated promptly, the clinical and imaging abnormalities of hypertensive encephalopathy resolve within a few days. However, during acute ischemic stroke, endogenously elevated blood pressure may benefit the ischemic tissue, and lowering the blood pressure at this time seems to be detrimental.