- Diseases, Disorders & Conditions
Malignant Hypertension - A Severe Form Of High Blood Pressure
Malignant Hypertension is a medical emergency
The term "Malignant Hypertension" is a misnomer, as this condition is not cancer, but an extreme form of high blood pressure.In true words, it is a hypertensive emergency. In this condition, the diastolic blood pressure is greater than, or equal to 120 mm Hg, and the systolic blood pressure is higher than, or equal to 180 mm of Hg. It presents as severe headache, vomiting, visual disturbances, including transient blindness, transient paralysis, convulsions, stupor, and coma. These manifestations have been attributed to spasm of blood vessels, and swelling or oedema of the brain. Multiple blood clots develop in arteries supplying the brain. Heart failure and rapidly declining kidney functions are other critical features of this condition. At times, it may even present as reduced or total lack of urine output, medically termed as oliguria or anuria respectively. Severe damage or necrosis of muscles in the walls of arteries also occurs.
Risk Factors Of Malignant Hypertension
The malignant phase of high blood pressure can occur in the course of both "Essential hypertension" , and that which occurs secondary to kidney failure and hormonal imbalance. This condition is common in 40 something men, who are affected more often than women. It can also occur in individuals suffering from the following diseases:
- Autoimmune conditions, such as SLE (Systemic Lupus Erythematosus), Systemic Sclerosis, and Polyarteritis Nodosa.
- Toxemia of Pregnancy.
- Kidney disorders.
Conditions that further aggravate the risk:
- Kidney failure
- Renal Artery Stenosis leading to Secondary Hypertension.
Uncontrolled high blood pressure causes multi organ damage
Internal Damage Due To Malignant Hypertension
At least two independent processes are believed to play a role in the causation of this condition. These include the following:
- Dilatation or widening of blood vessels supplying the brain. This occurs because the normal auto regulation of cerebral blood flow decompensates as a result of markedly elevated blood pressure. Blood flow to the brain, therefore, is excessive, producing encephalopathy (inflammation and swelling of the brain) associated with this condition.
- Generalized necrosis or damage to the walls of arterioles.
Many individuals also suffer from anemia due to massive destruction of red blood cells. This phenomenon further contributes to the deterioration of kidney functions.
Many individuals suffering from malignant hypertension have an undetected tumor of the adrenal gland, known a pheochromocytoma, that secretes adrenaline and related hormones, which then result in a steep rise in blood pressure. In adults, a majority of these tumors are unilateral, solitary, and present on the right side. This condition is common in young to mid-adult life.
High blood pressure increases the risk of heart attacks
Warning Signs of Malignant Hypertension
- Severe headache
- Changes in mental status, such as sudden, severe anxiety, depression, feeling of an impending doom, reduced alertness, reduced ability to concentrate, tiredness, restlessness, sleepiness, stupor, and lethargy.
- Blurred vision
- Chest pain
- Nausea or vomiting
- Numbness and weakness of arms, legs, face or other areas
- Seizures or epileptic fits
- Reduced urine output
- Shortness of breath
- Swelling of lower legs and feet
- Extremely high blood pressure
- Abnormal heart beats and fluid in lungs.
- Eye signs, such as retinal hemorrhages, narrowing of retinal arteries, and swelling of the optic nerve.
Extremely high blood pressure can lead to brain attacks
Effects of Untreated High Blood Pressure on Our Body
These include the following:
- Effects on the heart: Uncontrolled high blood pressure puts an excessive load on the heart, that has to work harder to pump the blood. As a compensation, muscle layer of the wall of the left chamber (left ventricle) of the heart thickens. This causes difficulty in breathing on exertion and spells of breathlessness during sleep. When blood pressure rises further, and the heart is unable to compensate, then its functions gradually deteriorate, and it begins to dilate, resulting in heart failure. Angina pectoris, a severe pain in the left side of the chest, provoked by exertion, can also occur due to increased oxygen requirements of an overworked heart, in the absence of which the heart begins to starve, resulting in pain. Heart attacks and irregular beats also occur.
- Effects on the eye: Longstanding, progressive high blood pressure leads to focal spasm and generalized narrowing of the arterioles supplying retina of the eye. Hemorrhages, exudates, and papilloedema (or swelling of the optic disc of the retina) are also common. These changes often produce a blind spot in front of the visual fields, blurred vision, and even blindness, especially when these hemorrhages involve macula of the eye. Complete resolution of these lesions occurs, if anti hypertensive therapy is started immediately and results in a significant reduction in blood pressure. Retinal arteriosclerosis or hardening of the small blood vessels supplying retina of the eye accompanies, and occurs at an accelerated pace in longstanding high blood pressure. It results from thickening of the inner lining and the middle muscle layer of these blood vessels and accurately reflects similar changes in other organs. Since the retina is the only structure in which the supplying arterioles or blood vessels can be examined directly, repeated ophthalmoscopic examination provides an opportunity to observe the effects of high blood pressure.
- Effects on brain and central nervous system: Occipital headaches involving back of the head just above the neck are a common occurrence early in the morning. They may be accompanied by episodes of dizziness, vertigo, ringing of ears or tinnitus, dimmed vision and syncope or sudden episodes of faintness. Extremely high blood pressure can lead to a brain attack or stroke, brain hemorrhage, and hardening of vessels supplying the head region. It also leads to dilatations in walls of the arteries, called microaneurysms. Hypertensive encephalopathy is a medical emergency. It presents as a severe elevation in blood pressure, altered consciousness, increased pressure within the brain, retinopathy with swelling of the optic disc, and fits or seizures. This complication is more closely related with the increase in systolic blood pressure. Preceding high blood pressure increases the chances of subsequent dementia, of both vascular and Alzheimer's types.
- Effects on the kidney: Longstanding high blood pressure causes hardening of arteries and capillaries supplying the kidneys. This gradually leads to deterioration in the kidney functions, and appearance of proteins and blood in urine, that ultimately culminate into renal failure.
- Aortic Dissection: Uncontrolled high blood pressure leads to sudden tears in the wall of the aorta, the largest supplying artery. This is a life-threatening condition, that presents as a sudden, severe chest pain with radiation to the back.
Malignant Hypertension: www.nlm.nih.gov/medlineplus/ency/article/000491.html