What is Malignant Hypertension?
“Malignant hypertension” is a term previously used for patients with very high blood pressure and various serious complications, suggesting a bleak outlook. These days, we refer to it as a “hypertensive crisis”. This condition occurs when a patient experiences a severe increase in blood pressure, specifically:
* Systolic blood pressure, the pressure when your heart beats, being over 180 mm Hg
* Diastolic blood pressure, the pressure when your heart is at rest, being over 120 mm Hg
We can break down this diagnosis further into “hypertensive emergency”: a steep rise in blood pressure causing damage to other organs, and “hypertensive urgency”: a significant hike in blood pressure without causing harm to other organs. Timely treatment of the high blood pressure can help avoid a hypertensive emergency and, as a result, prevent severe, life-threatening complications.
One of the vital criteria for diagnosing malignant hypertension includes the presence of papilledema, a condition causing swelling in the optic disk. The important thing in managing malignant hypertension is to reduce the high blood pressure within a few hours.
What Causes Malignant Hypertension?
There are many factors that can cause severe high blood pressure, also known as a hypertensive crisis. These include:
* Not taking prescribed medication regularly
* Diseases affecting the blood vessels in the kidneys, like narrowing of the renal arteries, systemic conditions like polyarteritis nodosa and Takayasu arteritis
* Kidney diseases including those which alter kidney structure like glomerulonephritis, tubulointerstitial nephritis, and systemic diseases like systemic sclerosis, hemolytic-uremic syndrome, and systemic lupus erythematosus
* Gland-related disorders such as pheochromocytoma, Cushing’s disease, excess production of the hormone aldosterone, and tumors secreting the hormone renin
* Narrowing of the aorta, the main blood vessel supplying oxygenated blood to the body; drug use or exposure to certain substances, including cocaine, phencyclidine, sympathomimetics, erythropoietin, and cyclosporine
* Suddenly stopping blood pressure lowering medication
* Amphetamine use
* Brain-related conditions, such as those caused by a head injury, blockage or rupture of blood vessels in the brain.
Risk Factors and Frequency for Malignant Hypertension
Hypertensive emergencies, or extremely high blood pressure situations, are quite rare, with an expected rate of 1 to 2 cases out of a million people each year. Despite this, recent research indicates that the number of visits to the emergency department because of high blood pressure emergencies has doubled from 2006 to 2013.
- Eclampsia, a condition related to high blood pressure during pregnancy, represents 2% of these cases.
- Cerebral infarction, a type of stroke caused by interrupted blood flow to the brain, makes up 39% of the cases.
- Acute pulmonary edema, a condition where fluid accumulates in the lungs, constitutes 25% of hypertensive emergency cases.
Signs and Symptoms of Malignant Hypertension
Hypertensive emergency is a severe form of high blood pressure and most people with this condition have had high blood pressure for years before they experience a hypertensive emergency. Healthcare professionals will typically ask patients questions to identify signs of damage to important organs. These signs can include headaches, feeling sick or vomiting, problems with vision, pain in the chest or back, shortness of breath, or difficulties when trying to breathe while lying down. It’s also important to review all the medicines a person is taking, whether they’re prescription or over-the-counter drugs, and details about when the last dose was taken. Questions about the use of recreational drugs like amphetamines, cocaine, or PCP will also be asked.
During the physical exam, blood pressure will be checked on both arms using a blood pressure cuff that fits properly. An examination of the back of the eyes may reveal signs of damage, like bleeding, buildup of fatty deposits, or swelling of the optic nerve. Heart failure might be detected by finding unusual heart sounds, like murmurs or gallops. Additionally, healthcare professionals will check for signs of fluid buildup in the lungs, abnormal sounds in the abdomen, or unusual behavior and responses suggestive of neurological effects.
- High blood pressure for years before a hypertensive emergency occurs
- Possible signs of damage to essential organs, like headaches, nausea or vomiting, vision problems, chest or back pain, shortness of breath, or problems breathing while lying down
- Evaluation of all medications used, adherence, and timing of the last dose
- Assessment of recreational drug use
- Checking blood pressure on both arms
- Examining the back of the eyes for bleeding, fatty deposits, or optic nerve swelling
- Listening for heart murmurs or gallops which could indicate heart failure
- Checking for signs of fluid in the lungs or unusual noises in the abdomen
- Looking out for confusing or unresponsive behavior, which might suggest damage to the brain
Testing for Malignant Hypertension
If a patient comes in with extremely high blood pressure or an sudden increase from a normal baseline, it’s absolutely essential to thoroughly evaluate their history and carry out a physical examination. This is crucial even when the patient’s blood pressure is under 180/120 mm Hg. From there, doctors should run a series of tests to check if there’s any damage to the body’s organs. Such damage might be responsible for specific symptoms the patient is experiencing.
These tests include:
* An electrocardiogram to check the heart’s activity
* A chest x-ray for a look at the lungs and heart
* Urinalysis to test the urine
* Checking electrolyte and creatinine levels in the blood
* Checking for signs of a heart attack if the patient is suspected to have an acute coronary condition
* A toxicology screen or drug test
* An MRI or CT scan of the brain if the patient has had a head injury, is showing neurological symptoms, has hypertensive retinopathy, or is experiencing nausea or vomiting
* A contrast CT or MRI scan of the chest, or a TEE (transesophageal echocardiogram) if doctors suspect the patient’s aorta (the main artery that carries blood away from the heart) might be dissected or torn
In general, it’s often simpler to categorize urgent cases of high blood pressure by the organ that’s suffering the most damage. The above tests can usually highlight which organ is under threat, and instruct management such as setting the target blood pressure and determining the speed at which it should be reached.
During the cardiac examination, doctors may discover signs of a heart attack, congestive heart failure, or fluid accumulation in the lungs (pulmonary edema). Thickening of the heart muscle, particularly on the left side, is often observed. To rule out aortic dissection, the blood pressure in both arms should be checked. The patient may also have a bruit, an abnormal sound caused by turbulent blood flow, in the neck and groin.
A look at the central nervous system can reveal symptoms such as a headache, changes in vision, vomiting, confusion, and seizures. An eye exam is important to look for signs like demarcated splashes of white (soft exudates), eroding, flame-shaped hemorrhages, and swelling of the optic nerve (papilledema).
A kidney evaluation can reveal decreased urine production (oliguria). Patients may further exhibit gastrointestinal symptoms like nausea, vomiting, and non-specific abdominal pain.
Treatment Options for Malignant Hypertension
For serious high blood pressure emergencies, the treatment, including the choice of medication and blood pressure goal, varies depending on the specific emergency and the organ that’s affected.
Generally, it’s not recommended to decrease blood pressure too quickly or too much, as this can cause harm to blood vessels that have become used to high blood pressure. In most high blood pressure emergencies, the goal is to reduce the average blood pressure by about 10 to 20% in the first hour, and then by another 5 to 15% over the next 24 hours. This usually results in a target blood pressure of less than 180/120 mm Hg for the first hour and less than 160/110 mm Hg for the next 24 hours, but rarely lower than 130/80 mm Hg over that period.
Common medications and their doses used to treat these emergencies include:
– Nicardipine
– Sodium nitroprusside
– Labetalol
– Esmolol
In some cases, where blood pressure measurements might be over or underestimated, or where the organ damage could be life-threatening, a procedure called arterial catheterization might be considered. This provides precise, real-time blood pressure measurements.
Some exceptions to gradual blood pressure lowering over the day include certain serious conditions like stroke, aortic dissection, brain hemorrhage, and heart artery blockage. These conditions may require different treatment approaches and goals.
After a period of good blood pressure control, usually 8 to 24 hours, oral medications can typically be started, and the initial intravenous therapy is gradually reduced and stopped.
What else can Malignant Hypertension be?
When trying to diagnose high blood pressure, doctors have to consider various other medical conditions that may present similar symptoms. These conditions include:
- Acute kidney injury (a sudden episode of kidney failure or kidney damage)
- Aortic coarctation (a narrowing of the large blood vessel that branches off your heart)
- Aortic dissection (a serious condition where there is a tear in the wall of the major artery carrying blood out of the heart)
- Chronic kidney disease (long-term loss of kidney function)
- Eclampsia (a severe complication of pregnancy characterized by high blood pressure)
- Hypercalcemia (too much calcium in your blood)
- Hyperthyroidism (the overproduction of thyroid hormones)
- Pheochromocytoma (a rare tumor of the adrenal glands)
- Renal artery stenosis (the narrowing of the arteries that carry blood to your kidneys)
- Subarachnoid hemorrhage (a life-threatening type of stroke caused by bleeding into the space surrounding the brain)
For an accurate diagnosis, the doctor will need to thoroughly evaluate these possibilities and conduct the relevant tests.
What to expect with Malignant Hypertension
The outlook for those with malignant hypertension, a serious form of high blood pressure, is uncertain. Studies show that survival rates for patients who receive treatment within five years ranges from 75% to 84%. Without treatment, life expectancy is often less than two years. The most common causes of death in these cases are heart failure, stroke, or kidney failure.
Possible Complications When Diagnosed with Malignant Hypertension
There are several complications that may occur when target organs are impacted. These include:
- Encephalopathy: a brain disease that alters brain function or structure
- Intracerebral hemorrhage: bleeding within the brain
- Acute myocardial infarction: also known as a heart attack
- Acute heart failure: sudden onset of heart failure
- Pulmonary edema: accumulation of fluid in the lungs
- Unstable angina: unpredictably occurring chest pain
- Dissecting aortic aneurysm: a serious condition where the large blood vessel branching off the heart tears
- Acute kidney injury: sudden decrease in kidney function
- Vision loss: partial or total loss of sight
