Heart failure is a condition in which the heart has lost the ability to pump enough blood to the body's tissues. With too little blood being delivered, the organs and other tissues do not receive enough oxygen and nutrients to function properly.
According to the American Heart Association, about 4.9 million Americans are living with congestive heart failure. Of these, 2.5 million are males and 2.4 million are females. Ten of every 1,000 people over age 65 have this condition. There are about 400,000 new cases each year.
Heart failure happens when a disease affects the heart's ability to deliver enough blood to the body's tissues. Often, a person with heart failure may have a buildup of fluid in the tissues, called edema
. Heart failure with this kind of fluid buildup is called congestive heart failure. Where edema occurs in the body depends on the part of the heart that is affected by heart failure. Heart failure caused by abnormality of the lower left chamber of the heart (left ventricle) means that the left ventricle cannot pump blood out to the body as fast as it returns from the lungs. Because blood cannot get back to the heart, it begins to back up in the blood vessels of the lungs. Some of the fluid in the blood is forced into the breathing space of the lungs, causing pulmonary edema
. A person with pulmonary edema has shortness of breath, which may be acute, severe and life threatening. A person with congestive heart failure feels tired because not enough blood circulates to supply the body's tissues with the oxygen and nutrients they need. Abnormalities of the heart structure and rhythm also can be responsible for left ventricular congestive heart failure.
In right-sided heart failure, the lower right chamber of the heart (right ventricle) cannot pump blood to the lungs as fast as it returns from the body through the veins. Blood then engorges the right side of the heart and the veins. Fluid backed up in the veins is forced out into the tissues, causing swelling (edema), usually in the feet and legs. Congestive heart failure of the right ventricle often is caused by abnormalities of the heart valves and lung disorders.
When the heart cannot pump enough blood, it tries to make up for this by becoming larger. By becoming enlarged (hypertrophic) the ventricle can contract more strongly and pump more blood. When this happens, the heart chamber becomes larger and the muscle in the heart wall becomes thicker. The heart also compensates by pumping more often to improve blood output and circulation. The kidneys try to compensate for a failing heart by retaining more salt and water to increase the volume of blood. This extra fluid also can cause edema. Eventually, as the condition worsens over time these measures are not enough to keep the heart pumping enough blood needed by the body. Kidneys often weaken under these circumstances, further aggravating the situation and making therapy more difficult.
For most people, heart failure is a chronic disease with no cure. However, it can be managed and treated with medicines and changes in diet, exercise, and life-style habits. Heart transplantation
is considered in some cases.
Causes and symptoms
The most common causes of heart failure are:
The most common cause of heart failure is coronary artery disease. In coronary artery disease, the arteries supplying blood to the heart become narrowed or blocked. When blood flow to an area of the heart is completely blocked, the person has a heart attack
. Some heart attacks go unrecognized. The heart muscle suffers damage when its blood supply is reduced or blocked. If the damage affects the heart's ability to pump blood, heart failure develops.
Cardiomyopathy is a general term for disease of the heart muscle. Cardiomyopathy may be caused by coronary artery disease and various other heart problems. Sometimes the cause of cardiomyopathy cannot be found. In these cases the heart muscle disease is called idiopathic cardiomyopathy. Whatever the cause, cardiomyopathy can weaken the heart, leading to heart failure.
High blood pressure is another common cause of heart failure. High blood pressure makes the heart work harder to pump blood. After a while, the heart cannot keep up and the symptoms of heart failure develop.
Defects of the heart valves, congenital heart diseases, alcoholism, and drug abuse cause damage to the heart that can all lead to heart failure.
A person with heart failure may experience the following:
A person with left-sided heart failure may have shortness of breath and coughing caused by the fluid buildup in the lungs. Pulmonary edema may cause the person to cough
up bubbly phlegm that contains blood. With right-sided heart failure, fluid build-up in the veins and body tissues causes swelling in the feet, legs, and abdomen. When body tissues, such as organs and muscles, do not receive enough oxygen and nutrients they cannot function as well, leading to tiredness and dizziness.
Diagnosis of heart failure is based on:
A person's symptoms can provide important clues to the presence of heart failure. Shortness of breath while engaging in activities and episodes of shortness of breath that wake a person from sleep are classic symptoms of heart failure. During the physical examination, the physician listens to the heart and lungs with a stethoscope for telltale signs of heart failure. Irregular heart sounds, "gallops," a rapid heart rate, and murmurs of the heart valves may be heard. If there is fluid in the lungs a crackling sound may be heard. Rapid breathing or other changes in breathing may also be present. Patients with heart failure also may have a rapid pulse.
By pressing on the abdomen, the physician can feel if the liver is enlarged. The skin of the fingers and toes may have a bluish tint and feel cool if not enough oxygen is reaching them.
A chest x ray can show if there is fluid in the lungs and if the heart is enlarged. Abnormalities of heart valves and other structures also may be seen on chest x ray.
An electrocardiogram gives information on the heart rhythm and the size of the heart. It can show if the heart chamber is enlarged and if there is damage to the heart muscle from blocked arteries.
Besides chest x ray, other imaging tests may help make a diagnosis. Echocardiography
uses sound waves to make images of the heart. These images can show if the heart wall or chambers are enlarged and if there are any abnormalities of the heart valves. An echocardiogram also can be used to find out how much blood the heart is pumping. It determines the amount of blood in the ventricle (ventricular volume) and the amount of blood the ventricle pumps each time it beats (called the ejection fraction). A healthy heart pumps at least one-half the amount of blood in the left ventricle with each heartbeat. Radionuclide ventriculography also measures the ejection fraction by imaging with very low doses of an injected radioactive substance as it travels through the heart.
A new test that measures the level of a particular hormone in the blood was introduced in 2003 and researchers said the test may be useful for testing for heart failure in physicians' offices because it could provide results in 15 minutes.
Cardiac catheterization involves using a small tube (catheter) that is inserted through a blood vessel into the heart. It is used to measure pressure in the heart and the amount of blood pumped by the heart. This test can help find abnormalities of the coronary arteries, heart valves, and heart muscle, and other blood vessels. Combined with echocardiography and other tests, cardiac catheterization can help find the cause of heart failure. It is not always necessary, however.
Heart failure usually is treated with lifestyle changes and medicines. Sometimes surgery is needed to correct abnormalities of the heart or heart valves. Heart transplantation is a last resort to be considered in certain cases.
Dietary changes to maintain proper weight and reduce salt intake may be needed. Reducing salt intake helps to lessen swelling in the legs, feet, and abdomen. Appropriate exercise
also may be recommended, but it is important that heart failure patients only begin an exercise program with the advice of their doctors. Walking, bicycling, swimming, or low-impact aerobic exercises may be recommended. There are good heart rehabilitation
programs at most larger hospitals.
Other lifestyle changes that may reduce the symptoms of heart failure include stopping smoking or other tobacco use, eliminating or reducing alcohol consumption, and not using harmful drugs.
One or more of the following types of medicines may be prescribed for heart failure:
- beta blockers
- angiotensin converting enzyme inhibitors (ACE inhibitors)
- angiotensin receptor blockers (ARBs)
- calcium channel blockers
Diuretics help eliminate excess salt and water from the kidneys by making patients urinate more often. This helps reduce the swelling caused by fluid buildup in the tissues. Digitalis helps the heart muscle to have stronger pumping action. Vasodilators, ACE inhibitors, ARBs, and calcium channel blockers lower blood pressure and expand the blood vessels so blood can move more easily through them. This action makes it easier for the heart to pump blood through the vessels. Cholesterol-lowering drugs called statins can help prevent death from heart failure. A 2003 study showed a 62% drop in mortality rate among patients with severe heart failure who took statin therapy.
In 2003, a new noninvasive procedure was being tested for patients with congestive heart failure. Called enhanced external counterpulsation (EECP), it consisted of inflating three sets of pneumatic cuffs attached to the patient's legs. The therapy had positive effects on the blood pressure and reduced frequency of episodes of angina
(pain) in a clinical trial by as much as 70%.
Surgery is used to correct certain heart conditions that cause heart failure. Congenital heart defects and abnormal heart valves can be repaired with surgery. Blocked coronary arteries usually can be treated with angioplasty
or coronary artery bypass surgery.
With severe heart failure, the heart muscle may become so damaged that available treatments do not help. Patients with this stage of heart failure are said to have end-stage heart failure. Heart transplant usually is considered for patients with end-stage heart failure when all other treatments have stopped working.
Most patients with mild or moderate heart failure can be successfully treated with dietary and exercise programs and the right medications. In fact, in 2003, the American Heart Association said that even those awaiting heart transplants could benefit from exercise. Many people are able to participate in normal daily activities and lead relatively active lives.
Patients with severe heart failure may eventually have to consider heart transplantation. Approximately 50% of patients diagnosed with congestive heart failure live for five years with the condition. Women with heart failure usually live longer than men with heart failure.
Heart failure usually is caused by the effects of some type of heart disease. The best way to try to prevent heart failure is to eat a healthy diet and get regular exercise, but many causes of heart failure cannot be prevented. People with risk factors for coronary disease (such as high blood pressure and high cholesterol levels) should work closely with their physician to reduce likelihood of heart attack and heart failure.
— A technique for treating blocked coronary arteries by inserting a catheter with a tiny balloon at the tip into the artery and inflating it.
— Buildup of a fatty substance called a plaque inside blood vessels.
— A diagnostic test for evaluating heart disease; a catheter is inserted into an artery and passed into the heart.
Congenital heart defects
— Abnormal formation of structures of the heart or of its major blood vessels present at birth.
Congestive heart failure
— A condition in which the heart cannot pump enough blood to supply the body's tissues with sufficient oxygen and nutrients; back up of blood in vessels and the lungs causes buildup of fluid (congestion) in the tissues.
— A drug that helps the heart muscle to have stronger pumping action.
— A type of drug that helps the kidneys eliminate excess salt and water.
— Swelling caused by fluid buildup in tissues.
— A measure of the portion of blood that is pumped out of a filled ventricle.
— Valves that regulate blood flow into and out of the heart chambers.
— Any drug that relaxes blood vessel walls.
Heart failure sometimes can be avoided by identifying and treating any conditions that might lead to heart disease. These include high blood pressure, alcoholism, and coronary artery disease. Regular blood pressure checks and obtaining immediate medical care for symptoms of coronary artery disease, such as chest pain, will help to get these conditions found and treated early, before they can damage the heart muscle.
A 2003 initiative called OPTIMIZE H-F was aimed at preventing severe heart failure and deaths among patients discharge from hospitals. The project created a registry or database of patients with heart failure that could be shared among hospitals. Finally, diagnosing and treating heart failure before the heart becomes severely damaged can improve the prognosis. With proper treatment, many patients may continue to lead active lives for a number of years.
"Even Heart Failure Patients Should Exercise." Clinician Reviews April 2003: 50-52.
Jancin, Bruce. "Noninvasive Procedure Eyed for Heart Failure: Enhanced External Counterpulsation." Family Practice News June 1, 2003: 12.
"New Care Initiative to Improve Outcomes for Heart Failure Patients." Heart Disease Weekly April 20, 2003: 45.
"Rapid Congestive Heart Failure Test a Useful Tool in Physician Offices." Heart Disease Weekly June 15, 2003: 19.
Zoler, Michael N. "Heart Failure Deaths Plunge with Statins." Internal Medicine News April 15, 2003: 35-41.
American Heart Association. 7320 Greenville Ave. Dallas, TX 75231. (214) 373-6300. http://www.americanheart.org.
National Heart, Lung and Blood Institute. PO Box 30105, Bethesda, MD 20824-0105. (301) 251-1222. http://www.nhlbi.nih.gov.
Texas Heart Institute. Heart Information Service. PO Box 20345, Houston, TX 77225-0345. http://www.tmc.edu/thi.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
inability of the heart to maintain cardiac output sufficient to meet the body's needs; it most often results from myocardial failure affecting the right or left ventricle.
backward heart failure a concept of heart failure emphasizing the resultant passive engorgement of the systemic venous system that.
congestive heart failure
(CHF) that which occurs as a result of impaired pumping capability of the heart that is not keeping up with the metabolic needs of body tissues and organs; it is associated with abnormal retention of water and sodium. It ranges from mild congestion with few symptoms to life-threatening fluid overload and heart failure. Congestive heart failure results in an inadequate supply of blood and oxygen to the body's cells. The decreased cardiac output causes an increase in the blood volume within the vascular system. Congestion within the blood vessels interferes with the movement of body fluids in and out of the various fluid compartments, so that fluid accumulates in the tissue spaces, causing edema.
There are three general kinds of pathologic conditions that can bring about congestive heart failure: (1) ventricular failure,
in which the contractions of the ventricles become weak and ineffective, as in myocardial ischemia from coronary artery disease; (2) mechanical failure
of the ventricles to fill with blood during the diastole phase of the cardiac cycle, which can occur when the mitral valve is narrowed, as in rheumatic mitral stenosis, or when there is an accumulation of fluid within the pericardial sac (cardiac tamponade
) pressing against the ventricles, preventing them from accepting a full load of blood; and (3) an overload
of blood in the ventricles during the systole phase of the cycle. High blood pressure
, aortic stenosis
, and aortic regurgitation
are some of the conditions that can cause ventricular overload.
Compensatory Mechanisms. In an attempt to compensate for inadequate pumping of the heart, the body uses three basic adaptive mechanisms which, though they are effective for a brief period of time, will eventually become insufficient to meet the oxygen needs of the body. These mechanisms are also responsible for many of the symptoms experienced by the patient with congestive heart failure.
First, the failing heart attempts to maintain a normal output of blood by enlarging its pumping chambers so that they are capable of holding a greater volume of blood. This increases the amount of blood ejected from the heart, but it also leads to fluid overload within the blood vessels and excessive accumulation of body fluids in all of the fluid compartments.
Second, the heart begins to increase its muscle mass in order to strengthen the force of its contractions. This results in ventricular hypertrophy and a need for more oxygen. Eventually, the coronary arteries can no longer meet the oxygen demands of the enlarged myocardium and the patient experiences angina pectoris owing to ischemia.
Third, there is a response from the sympathetic nervous system. The involuntary muscle of the heart is regulated by autonomic, or involuntary, innervation. In response to failing contractility of the myocardial cells, the sympathetic nervous system activates adaptive processes that increase the heart rate, redistribute peripheral blood flow, and retain urine. These mechanisms are responsible for the symptoms of diaphoresis, cool skin, tachycardia, cardiac arrhythmias, and oliguria.
The combined efforts of these three compensatory mechanisms achieve a fairly normal level of cardiac output for a period of time. During this phase of congestive heart failure, the patient is said to have compensated CHF. When these mechanisms are no longer effective the disease progresses to the final stage of impaired heart function and the patient has decompensated CHF.
. Left-sided heart failure produces dyspnea of varying intensity. In the early stages, shortness of breath occurs only when the patient is physically active. Later, as the heart action becomes more seriously impaired, the dyspnea is present even when the patient is resting. In advanced cases, the patient must sit up in order to breathe (orthopnea
). Attacks of breathlessness severe enough to wake the patient frequently occur during sleep (paroxysmal nocturnal dyspnea
). These attacks usually are accompanied by coughing and wheezing, and the patient seeks relief by sitting upright. Orthopnea and paroxysmal nocturnal dyspnea are related to congestion of the pulmonary blood vessels and edema of the lung tissues. They are aggravated by lying down because in the prone position quantities of blood in the lower extremities move upward into the blood vessels of the lungs.
Fluid retention is another common symptom of congestive heart failure. In left-sided failure there is higher than normal pressure of blood in the pulmonary vessels. This increased pressure forces fluid out of the intravascular compartment and into the tissue spaces of the lungs, causing pulmonary edema. Right-sided failure causes congestion in the capillaries of the peripheral circulation and results in edema and congestion of the liver, stomach, legs, and feet, and in the sacral region in bedridden patients.
Decreased cardiac output also affects the kidneys by reducing their blood supply, which in turn causes a decrease in the rate of glomerular filtration of plasma from the renal blood vessels into the renal tubules. Sodium and water not excreted in the urine are retained in the vascular system, adding to the blood volume. The diminished blood supply to the kidney also causes it to secrete renin, which indirectly stimulates the secretion of aldosterone from the adrenal gland. Aldosterone in turn acts on the renal tubules, causing them to increase reabsorption of sodium and water, and thus to further increase the volume of body fluids.
. Medical management of congestive heart failure is aimed at improving contractility of the heart, reducing salt and water retention, and providing rest for the heart muscle. Drugs used to accomplish these goals include digitalis
glycosides to slow and strengthen the heartbeat, vasodilators
such as nitroprusside and phentolamine to reduce resistance to the flow of blood being pumped from the heart, diuretics
to assist in the elimination of water and sodium in the urine, and angiotensin converting enzyme inhibitors
to reduce blood pressure, inhibit aldosterone release, and reduce peripheral arterial resistance. beta-blockers
are an important adjunct in treatment of heart failure, helping to decrease the sympathetic response. Electroconversion of atrial fibrillation
enlists the help of the atria to fill the ventricles to maximum capacity. Biventricular pacing
or restoration of cardiac synchrony
is helpful for patients with interventricular conduction delay and a wide QRS complex
Patient Care. Hospitalized patients with severe congestive heart failure present problems related to their needs for physical and mental rest, adequate aeration of the lungs and oxygenation of the tissues, prevention of circulatory stasis, maintenance of the integrity of the skin, restoration and maintenance of fluid and electrolyte balances, and adequate nutrition. The care plan should include frequent monitoring of the vital signs, intake and output, daily weight, serum electrolyte and blood gas levels, and nutritional intake. Patients are placed on sodium-restricted diets and limited fluid intake; they should have a good understanding of the reason for this before leaving the hospital. They should also have a plan for regular exercise as tolerated. Since it is likely that they will continue taking several kinds of medications after returning home, patients or family members should be taught about the pharmacologic action of each drug, the need for taking it exactly as prescribed, any precautions to be taken, and any untoward reactions that warrant notification of the physician, nurse practitioner, or physician's assistant.
Clinical portrait of congestive heart failure. (SOBOE=shortness of breath on exertion) From Jarvis, 1996.
forward heart failure a concept of heart failure emphasizing the inadequacy of cardiac output as the primary cause.
high-output heart failure that in which cardiac output remains high, associated with conditions such as hyperthyroidism, anemia, and emphysema.
left-sided heart failure (left ventricular heart failure) failure of the left ventricle to maintain a normal output of blood; it does not empty completely and thus cannot accept all the blood returning from the lungs via the pulmonary veins, which become engorged. Fluid seeps out of the veins through the pulmonary capillaries and collects in the interstitial tissue of the lung, causing pulmonary edema that eventually leads to right ventricular heart failure as well.
low-output heart failure that in which cardiac output is diminished, associated with cardiovascular diseases such as coronary artery disease, hypertension, and cardiomyopathy.
right-sided heart failure (right ventricular heart failure) failure of proper functioning of the right ventricle, with subsequent engorgement of the systemic veins, producing pitting edema, enlargement of the liver, and ascites.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.