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Malignant Hypertension
Causes Symptoms Treatment
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Malignant Hypertension and accelerated high
blood pressure are two emergency conditions which should be treated promptly. Both conditions
have same outcome and therapy. However Malignant hypertension is a complication of high blood
pressure characterized by very elevated high blood pressure, and organ damage in the
eyes, brain, lung and/or kidneys. It differs from other complications of hypertension in that
it is accompanied by papilledema. (Edema of optic disc of eye) Systolic and diastolic blood
pressures are usually greater than 240 and 120, respectively. While Accelerated high
blood pressure is condition with high blood pressure, target organ damage, on fundoscopy we
have flame shaped hemorrhages, or soft exudates, but without papilledema.
There are two things. Hypertensive Urgency and Hypertensive
emergency. In hypertensive urgency we don’t see any target organ damage while in emergency we see
target organ damage along with high blood pressure greater than systolic >220. Now depending
upon target organ damage you will decide whether you have hypertensive emergency or urgency. It is
essential to bring down high blood pressure in hypertensive emergency immediately, while in
urgency, bring down blood pressure very rapidly is not required.
Pathogenesis of malignant hypertension is fibrinoid necrosis of
arterioles and small arteries. Red blood cells are damaged as they flow through vessels obstructed
by fibrin deposition, resulting in microangiopathic hemolytic anemia. Another pathologic process is
the dilatation of cerebral arteries resulting in increased blood flow to brain which leads to
clinical manifestations of hypertensive encephalopathy. Common age is above 40 years and it is more
frequent in man rather than women. Black people are at higher risk of developing hypertensive
emergencies than the general population.
Target organs are mainly Kidney, CNS and Heart. So symptoms of
Malignant hypertension are oligurea, Headache, vomiting, nausea, chest pain, breathlessness,
paralysis, blurred vision. Most commonly heart and CNS are involved in malignant hypertension. The
pathogenesis is not fully understood. Up to 1% of patients with essential hypertension develop
malignant hypertension, and the reason some patients develop malignant hypertension while others do
not is unknown. Other causes include any form of secondary hypertension; use of cocaine, MAOIs, or
oral contraceptives; , beta-blockers, or alpha-stimulants. Renal artery stenosis, withdrawal of
alcohol, pheochromocytoma {most pheochromocytomas can be localized using CT scan of the adrenals},
aortic coarctation, complications of pregnancy and hyperaldosteronism are secondary
causes of hypertension. Main Investigations to access target organ damage are complete renal
profile, BSR, Chest Xray, ECG, Echocardiography, CBC, Thyroid function tests.
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Management of Malignant Hypertension
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Patient is admitted in Intensive Care Unit. An intravenous line
is taken for fluids and medications. The initial goal of therapy is to reduce the mean
arterial pressure by approximately 25% over the first 24-48 hours. However Hypertensive urgencies
do not mandate admission to a hospital. The goal of therapy is to reduce blood pressure within 24
hours, which can be achieved as an outpatient department. Initially, patients treated for malignant
hypertension are instructed to fast untill stable. Once stable, all patients with malignant
hypertension should take low salt diet, and should focus on weight lowering
diet. Activity is limited to bed rest until the patient is stable. Patients should be able to
resume normal activity as outpatients once their blood pressure has been
controlled.
Hospitalization is essential until the severe high blood pressure is under
control. Medications delivered through an IV line, such as nitroglycerin, nitroprusside, or
others, may reduce your blood pressure. An alternative for patients with renal
insufficiency is IV fenoldopam. Beta-blockade can be accomplished intravenously with esmolol
or metoprolol. Labetalol is another common alternative, providing easy transition from
IV to oral ( PO) dosing. Also available parenterally are enalapril, diltiazem, verapamil,
Hydralazine is reserved for use in pregnant patients as it also increases uterine profusion,
while phentolamine is the drug of choice for a pheochromocytoma crisis. After the severe high
blood pressure is brought under control, regular anti-hypertensive medications taken by mouth
can control your blood pressure. The medication may need to be adjusted
occasionally.
Remember, It is very necessary to control malignant hypertension,
otherwise it can lead to life threatening conditions like Heart Failure, Infarction, Kidney failure
and even blindness.
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