Heart failure

Definition
Heart failure (previously called congestive heart failure) is a chronic, progressive condition in which the heart can't adequately pump blood through the body.

Causes/associated factors
Heart failure is a complex condition that results from anything that impairs the ability of the heart to pump effectively. The most common cause of heart failure is coronary artery disease (blockage of one or more coronary arteries). Hypertension (high blood pressure) and diabetes also increase your risk of developing heart failure. Other risk factors for heart failure include:
heart valve disease
recent heart attack
congenital heart disease (heart defects that are present at birth)
cardiomyopathy (disease of the heart muscle, the myocardium)
abnormal heart rhythms
hyperthyroidism (overactive thyroid, the hormone that sets your metabolism)
hypothyroidism (underactive thyroid)
infections, including HIV (the virus that causes AIDS)
anemia (a condition marked by a decreased number of red blood cells or hemoglobin, a protein in red blood cells that contains iron)
alcoholism
certain medications, such as chemotherapy
obesity
cigarette smoking
high cholesterol and triglycerides
Heart failure can be classified in various ways. You may hear the terms systolic or diastolic, although components of both often exist at the same time. Systolic heart failure is characterized by the left ventricle's inability to contract effectively. The left ventricle (the main pumping chamber of the heart) compensates for its inability to get enough blood to the tissues by beating faster (a condition known as tachycardia) and eventually increasing in size). If blood backs up to the lungs, the fluid may cause symptoms such as shortness of breath. If the fluid buildup in the lung becomes severe, the condition is known as pulmonary edema.

Diastolic heart failure is characterized by a stiff heart muscle and may often have the same characteristics as systolic dysfunction. Diastolic heart failure is more common in the elderly who often have other conditions such as hypertension or coronary artery disease.

Classification
Heart failure is sometimes classified according to what level of exertion causes symptoms. This is known as the New York Heart Association Functional Classification of Heart Failure, and has four levels:

I. No symptoms or limitation of physical activity.

II. Moderate levels of activity cause fatigue or shortness of breath. (Symptoms occur when you exert yourself more than you usually do in your daily activities.)

III. Mild activity causes symptoms. (Symptoms occur with normal daily activity.)

IV. Symptoms occur at rest.

Stages of heart failure
A new classification separates heart failure into stages. Each is seen as a progression with a focus on detection, early intervention and treatment to prevent the progression to the next stage. Therapies may differ depending on the stage:

Stage A: High risk for heart failure (has an underlying medical condition such as hypertension, coronary artery disease or diabetes), but no symptoms or change in heart structure.

Stage B: Heart structure and function aren't normal, but no symptoms.

Stage C: Abnormal heart structure with symptoms or history of symptoms. Heart failure is advanced.

Stage D: Heart structure and function are abnormal, and symptoms are resistant to usual treatment. This is the most advanced and severe stage of heart failure.


Signs/symptoms
The symptoms of heart failure vary and depend on many factors. Symptoms may include:
shortness of breath with physical exertion
shortness of breath when lying flat
fatigue or weakness
swollen abdomen, legs or ankles
rapid or irregular heartbeat
enlarged abdomen
cough that may produce mucus or pink, frothy sputum
appetite loss or nausea
abdominal pain or discomfort
indigestion
feeling full after eating a small amount of food
weight gain
decreased tolerance for activity
wheezing

Diagnosis
Diagnosis of heart failure is made through a complete medical history and physical exam. To determine the severity and underlying cause of heart failure, you may need tests such as:
lab tests of blood and urine samples
electrocardiogram (a recording of the electrical activity of the heart)
chest X-ray
cardiac catheterization with coronary arteriography (a procedure using a thin, hollow tube to inject contrast dye into coronary arteries for X-ray imaging)
echocardiogram (using sound waves to study the heart)
nuclear test to get an accurate measure of the pumping capability of the heart

Treatment
Heart function may improve with proper treatment and lifestyle changes. Education, counseling, and advice on diet and exercise can all help support these lifestyle changes. Medications, surgery or other procedures may also be needed.
Education and counseling
Education by a nurse may include causes and treatments of heart failure, medication and their side effects, how to recognize if your symptoms are worsening, and when to call your doctor. A trained counselor may offer coping strategies to deal with the changes heart failure has made in your life.

Education and counseling benefits: Education and counseling can often lessen your chance of being hospitalized. Learning more about heart failure and how to manage the condition can improve your quality of life. You can learn how to take better care of yourself and also improve your coping skills.

Education and counseling risks: There's a chance that education and counseling may not decrease your chance of hospitalization for heart failure.
Dietary changes
It's important to reduce salt and fat intake and avoid alcoholic beverages when you have heart failure. Careful weight control may also be recommended. Sometimes, a sudden weight gain can mean your body is accumulating fluid. Discuss any weight gain with your doctor, especially if it's sudden. Generally, a 2-pound gain in one day or a 3-pound gain in one week is a warning sign that heart problems are worsening. If this is the case, your doctor may restrict your salt intake or add diuretics (which help the body get rid of excessive fluid accumulation in the tissues and lungs). In some cases, fluid restriction may also be necessary.

Dietary changes benefits: Reducing salt in your diet and losing weight will help lower your blood pressure and decrease the amount of fluid your body retains, thus easing your heart's workload. A low-fat diet can decrease your cholesterol and prevent further build up of plaque (fatty substances) in your blood vessels.

Dietary changes risks: Changing eating habits is sometimes difficult.
Exercise
Exercise programs are often done in the hospital. It may include warm-up exercises and riding an exercise bike with trained staff monitoring your blood pressure and pulse. Walking is a safe form of exercise done at home. Consult your doctor to determine what kind of exercise program is right for you.

Exercise benefits: Moderate exercise has been shown to improve the functioning of the heart, improve the symptoms of heart failure, and overall increase quality of life. It may also reduce your risk of complications and becoming hospitalized.

Exercise risks: If you exercise too strenuously, you may increase your symptoms.
Medication
Many medications are now available to treat heart failure. Because heart failure may result from many different conditions, the medications often target a specific body system. The sympathetic nervous system (SNS) and the renin-angiotensin-aldosterone system (RAS) are examples of body systems heart failure medications work on.

Always take your medication as your doctor prescribes, and fill prescriptions promptly so you do not run out of medication.

Angiotensin-converting enzyme (ACE) inhibitors are often the initial medication prescribed to treat heart failure. Angiotensin is a chemical your body releases in heart failure to retain fluid and salt. It also narrows your blood vessels and raises your blood pressure. ACE inhibitors stop the conversion of the chemical angiotensin I into angiotensin II, its active form.

ACE inhibitor benefits: ACE inhibitors lower blood pressure, slow the progression of heart failure, and promote long-term improvement in heart function. If you are at high risk for heart failure, ACE inhibitors can help delay its onset.

ACE inhibitor risks: Side effects include dizziness, cough, angioedema (swelling of the face and lips) and worsening of renal insufficiency (kidney disease).
Angiotensin II receptor blockers (ARBs) work by blocking the effects of angiotensin II.

ARB benefits: ARBs improve symptoms of heart failure. If ACE inhibitors are not tolerated, ARBs may be substituted.

ARB risks: The most common side effect of ARBs is dizziness. Worsening of renal insufficiency may also occur.
Thiazide diuretics (such as hydrochlorothiazide or HCTZ) may be prescribed for mild fluid retention, whereas a loop diuretic (such as furosemide) may be used for more severe heart failure or in combination with a thiazide diuretic. A potassium-sparing agent such as spironolactone may also be used for severe heart failure. It blocks aldosterone, a chemical that regulates water and salt balance.

Diuretic benefits: Diuretics can improve the signs and symptoms of fluid retention.

Diuretic risks: Diuretics promote the loss of extra fluid through urination, which may cause electrolyte imbalance and dehydration and lead to dangerous cardiac arrhythmias (irregular heartbeat).
Digitalis improves the heart's pumping action and can also help control rapid or irregular heart rhythms.

Digitalis benefits: If taken along with an ACE inhibitor and a diuretic, digitalis may improve symptoms of heart failure and reduce the chances of hospitalization.

Digitalis risks: Side effects include appetite loss, nausea and arrhythmias. Your blood will need to be monitored periodically to check the level of this medication.
Vasodilators, such as nitrates and hydralazine hydrochloride, can dilate the arteries, lower blood pressure, and reduce the heart's workload. Hydralazine may be used in combination with a nitrate. Another vasodilator called nesiritide (brand name Natrecor) can relieve shortness of breath. Nesiritide is a new medication approved by the U.S. Food and Drug Administration (FDA) to treat heart failure. It's a synthetic form of a human hormone. Its use is typically limited to hospitalized and critically ill patients.

Vasodilator benefits: Hydralazine and nitrates offer alternatives for those patients who are unable to take ACE inhibitors or ARBs due to low blood pressure or kidney disease. Nesiritide may improve symptoms in severe heart failure.

Vasodilator risks: Nitrates may cause headaches and low blood pressure. Hydralazine may cause gastrointestinal upset, headaches, fast heart rate and low blood pressure. Nesiritide may cause severe low blood pressure and is only given intravenously.
The medications listed above are often used in combination, which can make it possible to lower the dosages of each of the individual drugs and reduce the additive effects of the drugs.

Other medical conditions, such as angina pectoris (chest pain due to coronary artery disease) or hypertension (high blood pressure) may require additional medication. Be sure to tell your doctor what prescription and over-the-counter (OTC) medications you use, since interactions between medications may cause complications. For example, nonsteroidal anti-inflammatory medications (NSAIDs) can reduce the effectiveness of ACE inhibitors.

Surgery
Surgery can sometimes repair the underlying diseases or defects that are causing heart failure. In some cases, heart valves can be replaced, angioplasty can open up blocked blood vessels, or a bypass can improve blood flow. All these procedures can improve heart function, as well as decrease symptoms of heart failure if present. The risks vary by procedure, but all include the risks of bleeding, infection and possible death.

Cardiac resynchronization with a pacemaker (an electrical device that senses your heart rate and stimulates your heart to beat when it beats too slowly or not at all) is another new treatment being used for the treatment of heart failure.

Cardiac resynchronization benefits: This type of pacemaker has been shown to improve exercise tolerance and quality of life.

Cardiac resynchronization risks: Having a pacemaker places you at risk for developing an infection from surgery. It's also possible to have problems with the leads (wires).
Implantable cardiac defibrillators (ICDs) may be considered for people who have certain dangerous, sustained heart rhythms. A pacemaker and ICD combination is also available. It's placed under the skin of the upper chest. If it detects an abnormal heart rhythm, it delivers an electrical shock to convert the rhythm back to normal.

ICD benefits: ICDs can decrease your risk of dying from an abnormal heart rhythm.

ICD risks: Having an ICD places you at risk for developing an infection from surgery. It's also possible to have problems with the leads (wires) from the defibrillator.
Heart transplants are reserved for those in end-stage heart failure. A transplant may be considered if the heart damage is beyond repair, your health is adequate enough to ensure a smooth recovery, and a suitable donor organ is available. While a person waits for a heart transplant, a ventricular assist device may be implanted to improve the heart's pumping action.

Heart transplant benefits: A heart transplant can reduce your symptoms and lengthen your life. The one-year survival rate following transplantation is greater than 85 percent.

Heart transplant risks: Risks include waiting for a suitable donor organ to become available, rejection of the newly implanted heart, infection, and having to take immunosuppressive medications the rest of your life.

Complications
Heart failure may cause deterioration of general health over time. Areas that may suffer include sleep quality, general energy level, and ability to heal from wounds and illnesses. Heart failure may complicate other medical conditions, such as diabetes. Eventually, the heart may fail to pump or develop electrical instability and ventricular arrhythmias, which can be fatal.

Pregnancy-specific information
Pregnancy may precipitate or hasten the progression of heart failure due to the significant increase in blood volume and cardiac output during pregnancy, especially near the end of the pregnancy. You'll need special care throughout your pregnancy if you develop heart failure.

Senior-specific information
The risk of heart failure increases with age. In fact, it has been cited as the most common diagnosis for hospitalization in people older than age 65.

Prevention
People who have angina, diabetes or uncontrolled high blood pressure face an increased risk of heart failure. Prevention and treatment of these underlying conditions are vital. To modify your risk factors, consider the following suggestions.
If you smoke, quit.
Maintain a healthy weight for your height and age.
If you're overweight, ask your doctor to help you devise a weight-loss plan.
Eat a nutritious diet low in fat, cholesterol and sodium.
Exercise regularly according to your doctor's instructions.
Strictly limit alcohol intake.
Ask your doctor about the pneumococcal vaccine and an annual flu shot.