Malignant hypertension

Definition

Malignant hypertension is a sudden and rapid development of extremely high blood pressure. The lower (diastolic) blood pressure reading, which is normally around 80 mmHg, is often above 130 mmHg.

Alternative Names

Accelerated hypertension; Arteriolar nephrosclerosis; Nephrosclerosis - arteriolar; Hypertension - malignant; High blood pressure - malignant

Causes, incidence, and risk factors

The disorder affects about 1% of people with high blood pressure, including both children and adults. It is more common in younger adults, especially African American men. It also occurs in women with toxemia of pregnancy, and persons with kidney disorders or collagen vascular disorders.

You are at high risk for malignant hypertension if you have had kidney failure or renal hypertension caused by renal artery stenosis.

Symptoms

• Abnormal sensation (numbness) of the arms, legs, face, or other areas
• Blurred vision
• Change in mental status
  • Restlessness
  • Anxiety
  • Decreased alertness, decreased ability to concentrate
  • Fatigue
  • Sleepiness, stuporous, lethargic
  • Confusion
• Chest pain
  • Mid-chest location most common
  • Crushing or pressure sensation
• Cough
• Decreased urinary output
• Headache
• Nausea or vomiting
• Seizure
• Shortness of breath
• Weakness of the arms, legs, face, or other areas

Signs and tests

Malignant hypertension is a medical emergency.

A physical exam commonly shows:

• Extremely high blood pressure
• Possible swelling in the lower legs and feet
• Abnormal heart sounds and fluid in the lungs
• Changes in mental status, sensation, muscle ability, and reflexes

An eye examination will reveal changes that indicate high blood pressure, including swelling of the optic nerve, retinal bleeding, narrowing of the blood vessels in the eye area, or other problems with the retina.

If not already present, kidney failure may develop as a complication of malignant hypertension. Other complications may also develop.

Tests to determine damage to the kidneys may include:

• BUN
• Creatinine
• Arterial blood gas analysis
• Urinalysis

A chest x-ray may show lung congestion and an enlarged heart.

This disease may also alter the results of the following tests:

• Aldosterone
• Cardiac enzymes (markers of heart damage)
• Electrocardiogram (EKG)
• Renin
• Urinary casts (sediment)

Treatment

You will need to stay in the hospital until the severe high blood pressure is under control. Medications will be given through a vein to reduce your blood pressure. If there is fluid in your lungs, you will be given medicines called diuretics, which help the body remove fluid. Your doctor will consider giving you medications to protect the heart if there is evidence of heart damage.

After the severe high blood pressure is brought under control, blood pressure medicines taken by mouth can control the hypertension. Your medication may need to be adjusted occasionally. Hypertension can be difficult to control.

Expectations (prognosis)

Many body systems are in serious risk due to the extreme rise in blood pressure. Multiple organs of the body, including the brain, eyes, blood vessels, heart, and kidneys may be damaged. The blood vessels of the kidney are highly susceptible to damage caused by pressure, and kidney failure may develop, which may be permanent, requiring dialysis (kidney machine).

If treated promptly, malignant hypertension is often controlled without permanent complications. If it is not treated promptly, complications may be severe and life-threatening.

Complications

• Brain damage due to:
  • Coma
  • Hypertensive encephalopathy
  • Intracerebral hemorrhage (bleeding in the brain)
  • Seizures
  • Spasm or constriction of the arteries of the brain
  • Stroke
  • Swelling
• Heart damage, including:
  • Heart attack
  • Angina (chest pain due to narrowed blood vessels or weakened heart muscle)
  • Heart rhythm disturbances
• Kidney failure
• Permanent blindness
• Pulmonary edema

Calling your health care provider

Go to the emergency room or call your local emergency number (such as 911) if symptoms of malignant hypertension develop. This is an emergency condition.

Call your health care provider if you know you have poorly controlled high blood pressure.

Prevention

If you have high blood pressure, carefully monitoring your blood pressure and taking your medicines properly help to reduce the risk. Eat a healthy diet, one that is low in salt and low in fat.

References

Badr KF, Brenner BM. Vascular injury to the kidney. In: Fauci A , Kasper D, Longo DL, et al, eds. Harrison's Principals of Internal Medicine. 17th ed. New York, NY: McGraw Hill; 2008:chap 280.