Text B. Chronic Pericarditis

 

Chronic pericarditis is inflammation that results in fluid accumulation or thickening of the pericardium and that begins gradually and is long-lasting.

In chronic effusive pericarditis, fluid slowly ac­cumulates in the pericardium. Usually the cause is unknown, but the condition may be caused by cancer, tuberculosis, or low thyroid function. When possible, known causes are treated; if heart function is normal, doctors take a wait-and-see approach.

Chronic constrictive pericarditis is a rare disease that usually results when fibrous (scarlike) tissue forms around the heart. The fibrous tissue tends to contract over the years, compressing the heart and making it smaller. Compression increases the pressure in the veins that return blood to the heart because higher pressure is needed to fill the heart. Fluid backs up and then leaks out and ac­cumulates under the skin, in the abdomen, and sometimes in spaces around the lungs.

Causes

Any condition that causes acute pericarditis can cause chronic constrictive pericarditis, but usually the cause is unknown. The most common known causes of chronic constrictive pericarditis are viral infections and radiation treatment for breast cancer or lymphoma. Chronic constrictive pericarditis also may result from rheumatoid ar­thritis, systemic lupus erythematosus, a previous injury, heart surgery, or a bacterial infection. Pre­viously, tuberculosis was the most common cause in the United States, but today tuberculosis accounts for only 2 percent of cases. In Africa and India, tuberculosis is still the most common cause of all forms of pericarditis.

Symptoms and Diagnosis

Symptoms of chronic pericarditis include shortness of breath, coughing (because high pressure in the veins of the lungs pushes fluid into the air sacs), and fatigue (because the heart be­comes inefficient). Otherwise, the condition is painless. Fluid in the abdomen and the legs is also common.

Symptoms provide important clues that a per­son has chronic pericarditis, particularly if there's no other reason for reduced heart per­formance—such as high blood pressure, coro­nary artery disease, or heart valve disease. In chronic constrictive pericarditis, the heart usu­ally doesn't look abnormally large on chest x-rays, whereas in most other heart diseases, the heart is enlarged. Nearly half of those with chronic con­strictive pericarditis have calcium deposits in the pericardium that show up on x-rays.

Two types of procedures may confirm the di­agnosis. Cardiac catheterization can be used to measure blood pressure in the heart chambers and major blood vessels. Alternatively, a mag­netic resonance imaging (MRI) scan or a com­puted tomography (CT) scan can be used to measure the thickness of the pericardium. Nor­mally the pericardium is less than an eighth of an inch thick, but in chronic constrictive pericarditis it's usually a quarter of an inch thick or more.

Treatment

Although diuretics (drugs that remove excess fluid) may improve symptoms, the only possible cure is surgical removal of the pericardium. Sur­gery cures about 85 percent of people who un­dergo it. However, because the risk of death from this operation is 5 to 15 percent, most people don't have the operation unless the disease substantially interferes with daily activities.

 

Notes:

wait-and-see approach наблюдательный подход

breast cancer рак груди

deposit отложение; налет

Low Blood Pressure

 

Low blood pressure (hypotension) is blood pressure low enough to cause symptoms, such as dizziness and fainting.

Maintaining the pressure of blood as it leaves the heart and circulates throughout the body, like maintaining water pressure in the pipelines throughout a home, is essential. The pressure must be high enough to deliver oxygen and nutri­ents to all cells in the body and remove waste products from them. But if the blood pressure is too high, it can rupture a blood vessel and cause bleeding in the brain (hemorrhagic stroke) or other complications. If the blood pressure is too low, the blood can't supply enough oxygen and nutrients to the cells and properly remove wastes from them. However, healthy people with low nor­mal blood pressure at rest tend to live longer.

Text. Fainting

 

Fainting (syncope) is a sudden brief loss of con­sciousness.

Fainting is a symptom of an inadequate supply of oxygen and other nutrients to the brain, usually caused by a temporary decrease in blood flow. Such a decrease in blood flow can occur when­ever the body can't quickly compensate for a drop in blood pressure. For instance, if a person has an abnormal heart rhythm, the heart may be unable to increase its output of blood enough to com­pensate for the decrease in blood pressure. Peo­ple with such conditions may feel fine when rest­ing, but they feel faint when exercising because the body's demand for oxygen increases sud­denly; this fainting is called exertional or effort syncope. Often, the person faints after exercising. The reason: the heart is barely able to maintain adequate blood pressure during exercise; when the exercise stops, the heart rate begins to fall, but the blood vessels from the muscles remain dilated to remove metabolic waste products. Because of the combination of reduced heart output and increased capacity of the vessels, blood pres­sure falls and the person faints.

Obviously, blood volume decreases when a per­son bleeds. But it also may decrease when a per­son becomes dehydrated from conditions such as diarrhea, excessive sweating, and excessive urination, which often occurs with untreated di­abetes or Addison's disease.

Fainting also can result when the compensa­tory mechanisms are affected by signals sent via the nerves from other parts of the body. For ex­ample, an intestinal cramp may send a signal to the heart via the vagus nerve that slows the heart rate enough to cause a person to faint. Such faint­ing is called vasomotor or vasovagal syncope. Many other signals—including other pains, fear, and the sight of blood—can lead to this type of fainting.

Fainting from coughing (cough syncope) or uri­nating (micturition syncope) usually results when the amount of blood flowing back to the heart decreases during straining. Fainting caused by urinating is particularly common in the elderly. Swallowing syncope can accompany diseases of the esophagus.

Fainting may also result from a decrease in the number of red blood cells (anemia), a decrease in the level of blood sugar (hypoglycemia), or a de­crease in the level of carbon dioxide in the blood (hypocapnia) caused by overbreathing (hyper-ventilation). Sometimes, anxiety leads to hyperventilation. When the carbon dioxide level de­creases, the blood vessels in the brain contract, and the person may feel faint but not actually lose consciousness. Weight lifter's syncope may result from hyperventilating before lifting.

In rare cases, typically in the elderly, fainting may be part of a mild stroke in which the blood flow to a part of the brain suddenly decreases.

Symptoms

Dizziness or light-headedness may precede fainting, especially when a person is standing. Af­ter a person falls, the blood pressure increases, partly because the person is lying down and often because the cause of the fainting has passed. Get­ting up too quickly may cause the person to faint again.

When the cause is an abnormal heart rhythm, fainting begins and ends suddenly. Sometimes the person experiences palpitations (an awareness of the heart beating) just before fainting.

Orthostatic fainting occurs when a person sits up or stands too quickly. A related form of faint­ing, called parade ground syncope, occurs when a person stands still for a long time on a hot day. Because the leg muscles aren't being used, they don't push blood up toward the heart; therefore, blood pools in the leg veins, and blood pressure falls.

Vasovagal syncope may occur when a person is sitting or standing and is often preceded by nausea, weakness, yawning, blurring of vision, and sweating. The person becomes ghostly pale, the pulse becomes very slow, and the person faints.

Fainting that begins gradually with warning symptoms and also disappears gradually sug­gests changes in blood chemistry, such as de­creased levels of blood sugar (hypoglycemia) or decreased levels of carbon dioxide in the blood (hypocapnia) caused by hyperventilating. Hypocapnia is often preceded by a pins-and-needles sensation and chest discomfort.

Hysterical fainting is not a true faint. The per­son only appears to be unconscious but doesn't have a heart rate or blood pressure abnormality and doesn't sweat or turn pale.

Diagnosis

A doctor tries to determine the underlying cause of fainting because some causes are more serious than others. Heart disease, such as an abnormal heart rhythm or aortic valve stenosis, can be fatal; other causes are much less worri­some.

Factors that help a doctor make a diagnosis include the person's age when the fainting epi­sodes began, the circumstances under which fainting occurs, any warning signs before a faint­ing episode, and the steps that help the person recover—such as lying down, holding the breath, or drinking orange juice. Descriptions from wit­nesses of the fainting episode may be helpful. A doctor also needs to know whether the person has any medical conditions and whether the per­son is taking any prescription or nonprescription drugs.

A doctor may be able to re-create a fainting spell under safe conditions by asking the patient to breathe quickly and deeply. Or while monitoring the heartbeat with an electrocardiogram (ECG), a doctor may press gently over the carotid sinus (a portion of the internal carotid artery containing sensors that monitor blood pressure).

An electrocardiogram may indicate an under­lying heart or lung disease. To find the cause of fainting, a doctor may have a person wear a Holter monitor, a small device that records the heart's rhythms for 24 hours as the person engages in ordinary activities. If an irregular heart rhythm coincides with an episode of fainting, it's proba­bly—but not necessarily—the cause.

Other tests, such as echocardiography (an im­aging technique that uses ultrasound waves), can determine whether the heart has a structural or functional abnormality. Blood tests may show that the person has low blood sugar levels (hy­poglycemia) or low numbers of red blood cells (anemia). To diagnose epilepsy (which may oc­casionally be confused with fainting), a doctor may use electroencephalography, a test that shows patterns of electrical brain waves.

Treatment

Usually, lying flat is all that's needed for a per­son to regain consciousness. Raising the legs can speed up recovery by increasing blood flow to the heart and brain. If the person sits up too rapidly another fainting episode may occur.

In young people who don't have heart disease, fainting usually isn't serious, and extensive diag­nostic investigations and treatment rarely are necessary. However, in older people, fainting may result from several interrelated problems that prevent the heart and blood vessels from adjust­ing appropriately to a decrease in blood pressure. Treatment depends on the cause.

A heartbeat that's too slow can be corrected by surgically implanting a pacemaker, an electronic device that stimulates heartbeats. Drug therapy can be used to slow a heart rate that's too rapid. A defibrillator can be implanted to jolt the heart back into the normal rhythm if the heart beats irregularly from time to time. Other causes of fainting—such as hypoglycemia, anemia, or low blood volume – can be treated. Surgery is considered for problems with heart valves, regardless of the person’s age.

Notes:

pipeline трубопровод, магистраль

blurring of vision нечеткость, расплывчатость зрения spell промежуток времени; приступ болезни precede предшествовать

yawn зевать

regain consciousness прийти в себя (в сознание)

pacemaker электрокардиостимулятор

Shock

Text.

 

Shock is a life-threatening condition in which blood pressure is too low to sustain life.

Shock results when a low blood volume, an in­adequate pumping action of the heart, or exces­sive relaxation (dilation) of the blood vessel walls (vasodilatation) causes severe low blood pressure. This low blood pressure, which is much more se­vere and prolonged than in fainting (syncope), causes an inadequate blood supply to body cells. The cells can be quickly and irreversibly damaged and die.

Low blood volume may result from severe bleeding, an excessive loss of body fluids, or in­adequate fluid intake. Blood may be rapidly lost because of an accident or internal bleeding, such as that caused by an ulcer in the stomach or in­testine, a ruptured blood vessel, or a ruptured ectopic pregnancy (pregnancy outside the uterus). An excessive loss of other body fluids can occur with major burns, inflammation of the pan­creas (pancreatitis), perforation of the intestinal wall, severe diarrhea, kidney disease, or exces­sive use of strong drugs that increase the output of urine (diuretics). Despite feeling thirsty, people may not drink enough fluid to compensate for fluid losses if a physical disability (such as severe joint disease) prevents them from obtaining wa­ter without assistance.

An inadequate pumping action of the heart also can result in less than normal amounts of blood being pumped out with every heartbeat. The in­adequate pumping action may result from a heart attack, pulmonary embolism, failure of a heart valve (particularly an artificial valve), or an irreg­ular heartbeat.

Excessive dilation of the blood vessel walls may result from a head injury, liver failure, poisoning, overdoses of certain drugs, or severe bacterial infection. (Shock caused by such an infection is called septic shock.)

Symptoms and Diagnosis

Symptoms of shock are similar, whether the cause is low blood volume or inadequate pumping action of the heart. The condition may begin with tiredness, sleepiness, and confusion. The skin becomes cold and sweaty and often bluish and pale. If the skin is pressed, color returns much more slowly than normal. A bluish network of lines may appear under the skin. The pulse is weak and rapid, unless a slow heartbeat is causing the shock. The person usually breathes rapidly, but breathing and the pulse may both slow down if death is imminent. The blood pressure drops so low that it often can't be measured with a blood pressure cuff. Eventually, the person can't sit up without passing out and may die.

When shock results from excessive dilation of blood vessels, the symptoms are somewhat dif­ferent. For instance, the skin may be warm and flushed, particularly at first.

In the earliest stages of shock, especially septic shock, many symptoms may be absent or unde­tected unless they're specifically looked for. The blood pressure is very low. Urine flow is also very low, and waste products build up in the blood.

Prognosis and Treatment

If untreated, shock is usually fatal. If shock is treated, the outlook depends on the cause, other illnesses the person has, the amount of time be­fore treatment begins, and the type of treatment given. Regardless of treatment, the likelihood of death from shock after a massive heart attack or from septic shock in an elderly patient is high.

The first person to arrive on the scene should keep the victim warm and raise the legs slightly to facilitate the return of blood to the heart. Any bleeding should be stopped, and breathing should be checked. The victim's head should be turned to the side to prevent inhalation of vomit. Nothing should be given by mouth.

Emergency medical personnel may provide me­chanically assisted breathing. Any drugs are given intravenously. Narcotics, sedatives, and tranquilizers generally aren't given because they tend to decrease blood pressure. Attempts may be made to increase blood pressure with military (or medical) antishock trousers (MAST). These pants apply pressure to the lower body, thus driv­ing blood from the legs to the heart and brain. Fluid is given intravenously. Usually, blood is cross-matched before a blood transfusion, but in an urgent situation when there's no time for cross-matching, type 0 negative blood can be given to anyone.

The intravenous fluid and blood transfusion may be too little to counteract the shock if bleed­ing or fluid loss continues or if the shock is caused by a heart attack or another problem unrelated to blood volume. Drugs that constrict the blood vessels may be given to boost blood flow to the brain or heart, but they should be used as briefly as possible because they can reduce blood flow to the tissues.

When shock is caused by an inadequate pump­ing action of the heart, efforts are made to im­prove the heart's performance. The rate and rhythm abnormalities of the heartbeat are corrected, and blood volume is increased if necessary. Atropine may be used to increase a slow heartbeat, and other drugs may be given to improve ability of the heart muscle to contract.

In those with a heart attack, a balloon pump can be inserted into the aorta to reverse shock temporarily. After this procedure, emergency coronary artery bypass surgery or surgery to correct heart defects may be needed.

In some cases of shock after a heart attack, emergency percutaneous transluminal coronary angioplasty to open the blocked artery can improve the damaged heart's inadequate pumping action and the resulting shock. Before this procedure, patients usually receive intravenous drugs to break up clots (thrombolytic drugs). If emergency percutaneous transluminal coronary angioplasty or cardiac surgery is notperformed, a thrombolytic drug is given as soon as possible, unless it could worsen other medical problems the patient has.

Shock caused by excessive dilation of the blood vessels is treated primarily with drugs that constrict the vessels while the underlying cause of the excessive dilation can be corrected.

Notes:

sustain life поддерживать жизнь

confusion спутанность (сознания)

imminent близкий; надвигающийся, неизбежный

blood pressure cuff манжета танометра

 

High Blood Pressure

 

High blood pressure (hypertension) is generally a symptomless condition in which abnormally high pressure in the arteries increases the risk of prob­lems such as stroke, aneurysm, heart failure, heart attack, and kidney damage.

To many people, the word hypertension sug­gests excessive tension, nervousness, or stress. In medical terms, however, hypertension refers to a condition of elevated blood pressure, regard­less of the cause. It has been called "the silent killer" because it usually doesn't cause symptoms for many years—until a vital organ is damaged.