Heart failure is a condition in which the heart cannot pump enough blood to meet the body’s needs. A healthy heart can pump out 60 percent of the blood it receives in one beat; a failing heart pumps only 40 percent or less. Heart failure is not the same thing as a heart attack or cardiac arrest. Heart failure may develop either suddenly, in which case it is called acute heart failure, or slowly over a period of time, in which case it is called chronic heart failure.
Though most cases of heart failure involve both sides of the heart, it can be classified as left-sided or right-sided heart failure, depending on which side of the heart is affected. Left-sided heart failure is more common. In left-sided heart failure, the heart cannot pump enough oxygenated blood from the lungs to the rest of the body, leading to fluid buildup in the lungs. This buildup is called congestion, which is why heart failure is sometimes called congestive heart failure. The patient typically feels short of breath with left-sided heart failure. He or she may tire easily with even small amounts of exercise and have trouble breathing at night when lying flat.
In right-sided heart failure, the heart does not pump enough blood to the lungs to be oxygenated. As a result, fluid may collect in the patient’s feet, ankles, and abdomen, causing swelling in the feet and ankles. In some cases the liver also becomes enlarged, and the veins in the patient’s neck swell up.
Heart failure can occur in children or adolescents but is usually a disorder of adults. In most cases the symptoms develop slowly over a period of months and years and are often attributed to aging. As the heart muscle gradually weakens—often as the result of a disease like diabetes or longterm high blood pressure, damage caused by a heart attack, or a congenital abnormality of one of the heart valves—the heart works harder to meet the body’s needs for the oxygen and nutrients carried by the blood. As the heart becomes less efficient, the person often feels tired or lacking in energy. Heart failure is often not diagnosed until the person begins to develop fluid buildup in their feet or legs, lungs, abdomen, or liver. As the heart muscle is weakened, the heart tries to make up for its loss of strength in one or more of three ways. It may enlarge, which allows it to fill with more blood and so have more blood to pump to other parts of the body. Second, it may acquire more muscle mass, which allows it to pump blood more forcefully, at least for a time. Third, the heart may simply speed up and pump faster. In addition to the heart’s attempts to make up for its growing weakness, the body may also respond, either by narrowing its veins and arteries in order to maintain blood pressure, or by redirecting blood away from less vital parts of the body to the brain and heart, which are the most vital organs. These responses help to explain why some people can go on for years without being aware that their heart has lost some of its ability to function.
Heart failure is a common disorder in the general American population, particularly among older adults. According to the Centers for Disease Control and Prevention (CDC), about 5 million people in the United States were living with heart failure in 2008, with about 550,000 new cases diagnosed annually. More than 287,000 people die each year from heart failure in the United States. The disorder costs the country $30 billion each year in direct health care costs. Heart failure is more common among people over 65 than among younger adults. It is the most common reason for hospitalization for patients on Medicare. Among children, congenital (inborn) heart defects are the most common reason for heart failure.
Other risk factors for heart failure include:
• Sex. Men are more likely than women to develop heart failure; however, among adults over the age of 75, more women than men have the condition.
• Race. African Americans are more likely than members of other races to develop heart failure, to develop it at younger ages, to get worse faster, and to die from heart failure.
• Obesity. Excess weight puts a strain on the heart muscle.
• Diabetes. Diabetes increases a person’s risk of coronary artery disease and high blood pressure.
• History of coronary artery disease (narrowing of the arteries) or high blood pressure. Coronary artery disease lowers the supply of oxygen to the heart muscle.
• Virus infections that may have weakened the heart.
• Heart attack. A heart attack weakens the heart’s ability to pump blood. According to the CDC, 22 percent of men with heart attacks and 46 percent of women will develop heart failure within six years of the heart attack.
• Alcohol abuse. Too much alcohol can weaken the heart muscle.
• Sleep apnea. Sleep apnea lowers the supply of oxygen to the blood during the person’s sleep time and increases the risk of developing irregular heart rhythms as well as weakening the heart muscle.
• Kidney disease. Disorders of the kidneys increase the risk of heart failure because they lead to fluid retention and high blood pressure.
Nursing Care Plan Signs and Symptoms
The causes of heart failure include a number of factors that can weaken the heart’s ability to pump blood, ranging from congenital defects in the structure of the heart to infections, lifestyle choices, or other diseases and disorders in later life.
The most common symptoms of heart failure are:
• Shortness of breath. The person may have trouble sleeping unless propped up on pillows, or may wake up suddenly feeling short of breath.
• Persistent coughing or wheezing, or coughing up bloody mucus. This symptom is caused by fluid building up in the lungs.
• Swelling of the feet, ankles, or abdomen. The patient may gain several pounds of weight very suddenly or notice that their shoes feel tight.
• Tiredness and fatigue. The person may find that even minor tasks or chores, such as shopping or carrying a small bag of groceries, leave them unusually tired.
• Nausea and loss of appetite. Fluid building up in the abdomen affects the digestive tract, causing the person to feel full or sick.
• Memory loss and confusion.
• Rapid heartbeat. The patient may notice that the heart is beating faster and experience it as a racing or throbbing sensation.
• Need to urinate at night. In some people with swollen feet or ankles, the body is able to dispose of some of the fluid at night through the urine.
Nursing Care Plan Diagnosis
The diagnosis of heart failure is complicated because many of the symptoms of the disorder are not unique. The doctor will usually begin with the patient’s history and note such risk factors as a previous heart attack, diabetes, or high blood pressure. The doctor will then listen to the patient’s heart and lungs with a stethoscope to detect evidence of congestion in the lungs or abnormal heart sounds.
If the doctor suspects that the patient has heart failure, he or she will order one or more laboratory or imaging tests:
• Blood test. This may be done to rule out kidney disease as the cause of fluid retention or to test for the presence of a hormone that is found in the blood when the heart is overworked.
• Electrocardiogram (ECG). This test measures the electrical activity of the heart.
• Chest x ray. This imaging test can identify fluid in the lungs and enlargement of the heart.
• Echocardiogram. This is an important test that uses sound waves to produce an image of the heart on a video monitor. It can be used to measure the percentage of blood pumped out by the left ventricle—the heart’s main pumping chamber—with each beat.
• Stress tests. In these tests, the patient is either asked to exercise on a treadmill or is given a medication that stresses the heart to determine whether there are blockages in the heart’s arteries.
• Computed tomography (CT) or magnetic resonance imaging (MRI) scans of the heart.
• Cardiac catheterization. In this type of test, the doctor inserts a thin tube called a catheter into a blood vessel in the groin or arm and threads it through the aorta into the coronary arteries. Radioactive dye injected through the catheter makes the arteries and the left ventricle of the heart visible on an x ray.
Nursing Care Plan Treatment
Except for cases of heart failure caused by damaged heart valves (which can be corrected by surgery), heart failure cannot be cured but only controlled. Patients may be given one or more medications or surgical treatments to control their symptoms and prevent further damage to the heart.
Medications that may be prescribed to treat heart failure include:
• Diuretics. Sometimes called water pills, these are drugs that help the body get rid of excess fluid through the urine.
• ACE inhibitors. These are medications that lower blood pressure, improve blood flow, and decrease the workload on the heart.
• Digoxin. Also known as digitalis, this drug increases the strength of the heart’s contractions and slows down the heartbeat.
• Beta blockers. These medications slow heart rate, lower blood pressure, and reduce the risk of abnormal heart rhythms.
• Aldosterone antagonists. These drugs enable the body to get rid of salt and water through the urine, which lowers the volume of blood that the heart must pump.
Patients with acute heart failure may require treatment in a hospital. Hospital care usually includes oxygen therapy and medications (most commonly diuretics and drugs to relax the blood vessels) given intravenously. Severe heart failure that cannot be controlled by medications requires surgical treatment:
• Implantable cardioverter defibrillator (ICD). ICDs are devices that surgeons implant beneath the skin and attach to the heart with small wires. They monitor the heart rate and correct heart rhythms that are too fast.
• Cardiac resynchronization therapy (CRT). In this type of treatment, a pacemaker sends timed electrical impulses to both ventricles of the heart to coordinate their rhythm.
• Heart pump. A heart pump, sometimes called a left ventricular assist device or LVAD, is a device implanted in the abdomen and attached to a weakened heart to help it pump blood more efficiently. Originally used to keep candidates for heart transplants alive while they waited for a donor heart, LVADs are now thought of as alternatives to transplantation for some patients.
• Heart transplant.
Nursing Care Plan Prognosis
The prognosis of heart failure depends on the person’s age, sex, race, lifestyle, and other diseases they may have that affect the heart. Heart failure usually shortens a person’s life expectancy by several years. Between 5 and 20 percent of people hospitalized for acute heart failure die in the hospital.
Nursing Care Plan Prevention
Some causes of heart failure, such as congenital malformations, cannot be prevented. People can, however, lower their risk of heart failure in adult life by watching their weight, avoiding heavy drinking or the use of illegal drugs, getting regular exercise, and eating a diet focused on fruits, vegetables, whole grains, low-fat diary products, and lean meat. People being treated for diabetes, high blood pressure, or coronary artery disease can lower their risk of heart failure by taking all medications prescribed by their doctor, following their doctor’s recommendations about diet and exercise, and having regular checkups.
The Future
Heart failure is expected to continue to be a common disease of older adults in developed countries because of increasing life expectancy. Until the 1990s, doctors focused on controlling patients’ symptoms. More recently, however, doctors are recommending preventive health care and lifestyle changes in the early adult years, before people develop the symptoms of heart failure or other disorders that increase the risk of heart failure.
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