++
+++
Essentials of Diagnosis
++
The categories of uncontrolled hypertension and hypertensive emergency are based on the presence (hypertensive emergency) or absence (uncontrolled hypertension) of acute hypertension-mediated end-organ injury
These categories identify patients whose blood pressure (BP) must be controlled immediately from those whose BP control may safely be secured over hours to days
In a hypertensive emergency, the profile of organ injury will determine
The choice of anti-hypertensive agent
The rate at which BP should be reduced
The interval and final BP goal in response to therapy
+++
General Considerations
++
Multiple terms have historically described acute hypertensive syndromes (eg. hypertensive crisis, accelerated hypertension, hypertensive emergency, and malignant hypertension)
Some expert guidelines have condensed the terms into two categories: uncontrolled hypertension and hypertensive emergency
Uncontrolled hypertension
Hypertensive emergency
Defined as significant hypertension (usually but not always exceeding 180/120 mm Hg) that causes injury to the heart, retina, brain, kidneys, large arteries, or microcirculation
++
Uncontrolled hypertension
Hypertensive emergency
Often, the presence of organ injury is apparent from history or physical examination
Symptoms depend on the end organ involved
Acute hypertensive microangiopathy
Malignant hypertension is a complex of elevated blood pressure with retinopathy (retinal hemorrhages, cotton wool spots, or papilledema), acute kidney injury, and thrombotic microangiopathy
Hypertensive encephalopathy (headache, vomiting, seizures, lethargy, cortical blindness, or coma) that is not accompanied by classic hypertensive retinopathy occurs in about 10% of patients
Posterior reversible encephalopathy syndrome includes headache, seizures, altered consciousness, and disturbance of vision
Focal neurologic deficits may indicate cerebral infarction or hemorrhage
Abrupt onset of worst headache ever experienced: consider intracranial hemorrhage (intraparenchymal, ventricular, or subarachnoid)
Loss of consciousness and neck stiffness may be due to subarachnoid hemorrhage
Angina and dyspnea associated with acute elevation of left ventricular afterload
Chest or abdominal pain, usually severe, may be caused by aortic dissection or rupture
Back pain occurs with aortic dissection
Chest pain or dyspnea: cardiopulmonary involvement
Cardiac examination may reveal low A2, an S4, or a murmur of aortic regurgitation
Crackles on lung examination occur with heart failure
Papilledema is indictive of elevated intracranial pressure
Blurry or diminished vision occurs with retinal involvement
Other signs: absent pulses, asymmetric BP readings
In pregnant women or women of child-bearing age, preeclampsia or eclampsia should be excluded
+++
Differential Diagnosis
++
Any of the many causes of hypertension can lead to severe hypertension (see Hypertension, Chronic)
The underlying causes most likely to present in this way include
Poorly controlled or undiagnosed hypertension
Withdrawal from anti-hypertensive medications
Chronic kidney disease
Renal artery stenosis (atherosclerotic or fibromuscular dysplasia)
...