Hypertensive emergencies encompass a spectrum of clinical presentations in which uncontrolled blood pressures (BPs) lead to progressive or impending end-organ dysfunction. In these conditions, the BP should be lowered aggressively over minutes to hours.
Neurologic end-organ damage due to uncontrolled BP may include hypertensive encephalopathy, cerebral vascular accident/cerebral infarction, subarachnoid hemorrhage, and/or intracranial hemorrhage. Cardiovascular end-organ damage may include myocardial ischemia/infarction, acute left ventricular dysfunction, acute pulmonary edema, and/or aortic dissection. Other organ systems may also be affected by uncontrolled hypertension, which may lead to acute renal failure/insufficiency, retinopathy, eclampsia, or microangiopathic hemolytic anemia.
With the advent of antihypertensives, the incidence of hypertensive emergencies has declined from 7% to approximately 1% of patients with hypertension. In addition, the 1-year survival rate associated with this condition has increased from only 20% (prior to 1950) to a survival rate of more than 90% with appropriate medical treatment