Encyclopedia / C / Congestive Heart Failure

Congestive Heart Failure

What Is Congestive Heart Failure?

Congestive heart failure (CHF), also referred to as heart failure, is a serious condition marked by the inability of the heart to pump enough blood to meet the body’s oxygen demands. Heart failure can result from either a reduced ability of the heart muscle to contract or from a mechanical problem that limits the ability of the heart’s chambers to fill with blood. When weakened, the heart is unable to keep up with the demands placed upon it; blood returns to the heart faster than it can be pumped out causing back up or congestion—hence the name of the disorder. When the left side of the heart is failing, this backup results in fluid in the lungs (pulmonary edema). When the right side of the heart is failing, edema affects the liver and lower extremities (swelling of the feet, ankles, and lower legs).

The heart compensates in a number of ways. It beats faster and expands (dilates) somewhat more than usual as it fills with blood, so that when it contracts, more blood is forced out to the body. In addition, the decreased volume of blood reaching the kidneys causes them to stimulate a hormonal cascade (renin-angiotensin system), which results in the retention of sodium and water. These efforts help meet the body’s demands in the short term, but they ultimately have deleterious long-term effects. Faster beating allows less time for the heart to refill after contraction, so that less blood ends up being circulated. Also, the extra effort increases the heart muscle’s work and demand for oxygen.

Failure of the left side of the heart (left-sided failure) is more common. It leads to increased pressure in the pulmonary veins in the lungs, which forces fluid into the surrounding microscopic air sacs, or alveoli, that transfer oxygen to the bloodstream. As the alveoli fill with fluid, they no longer function properly, which limits the amount of oxygen available to the body and produces the most characteristic symptoms of congestive heart failure: fatigue and shortness of breath. In right-sided failure, the increased pressure in the veins returning blood from the rest of the body combined with the compensatory retention of sodium and water leads to fluid accumulation and swelling in the abdomen, liver, and legs. Often, both left- and right-sided heart failure occur together.

Congestive heart failure should not be confused with a heart attack, which involves sudden tissue death of the heart muscle. Although heart failure may occur suddenly in some cases, gradual loss of function is more common. Fatigue, shortness of breath on exertion, and increased frequency of nighttime urination develop and worsen over time. Shortness of breath is often worse when lying down—a condition known as orthopnea—as fluid from the legs pools in the lungs. Elevating the head with pillows eases chest congestion, but in advanced stages the patient may be unable to recline at all without severe breathlessness, and may need to sleep upright in a chair.

CHF occurs most frequently in those over age 60 and is the leading cause of hospitalization and death in that age group. In over 50% of cases, sudden death occurs due to a cardiac arrhythmia, or irregular heartbeat. Unfortunately, antiarrhythmic medications may not be effective in controlling arrhythmias caused by CHF.

There is no cure for heart failure, although measures are taken to treat the underlying cause, if possible. Restricted salt intake, and medication are used to ease the strain on the heart and to relieve symptoms. CHF is a serious health risk; for many patients the outlook is uncertain and depends on the extent of the disease and the patient’s response to therapy. However, with proper treatment it is possible for many patients to live with CHF and to manage many symptoms effectively. It is important that patients adhere to prescribed treatment regimens; noncompliance with a doctor’s recommendations regarding diet or medication increase the risk that the disease will worsen.

Who Gets Congestive Heart Failure?

According to the American Heart Association, nearly 5 million people experience heart failure and about 550,000 new cases are diagnosed each year in the United States. Heart failure becomes more prevalent with age and the number of cases is expected to grow as the overall age of the population increases.

The condition affects 1% of people aged 50 years and older and about 5% of those aged 75 years and older. African Americans experience heart failure twice as often as Caucasians. About 10% of patients diagnosed with heart failure die within 1 year, and about 50% die within 5 years of diagnosis.


  • Severe fatigue and weakness especially with exertion.

  • Irregular or rapid heartbeat.

  • Shortness of breath and wheezing after limited physical exertion. In advanced cases shortness of breath occurs even at rest, and attacks of severe breathlessness disturb sleep (left-sided failure).

  • Dry cough or cough that produces frothy or bloody sputum (left-sided failure).

  • Frequent urination during the night (right-sided failure).

  • Swelling of the ankles and feet, or swelling in the lower back if the patient is bedridden (right-sided failure).

  • Rapid weight gain due to fluid retention (right-sided failure).

  • Abdominal pain and a feeling of fullness (right-sided failure).

  • Swollen neck veins (right-sided failure).

  • Loss of appetite (anorexia); nausea and/or vomiting.

  • General feeling of poor health.

  • Anxiety; in severe cases irritability, restlessness, and mental confusion may occur.

Causes/Risk Factors

  • Risk factors for heart disease (e.g., smoking, being overweight, eating a diet high in fat and cholesterol, living a sedentary lifestyle) also increase the risk for heart failure.

  • Coronary artery disease (obstruction of the coronary arteries by atherosclerotic plaque so that heart tissue is starved of oxygen) often leads to a heart attack, which damages the heart muscle and causes CHF.

  • Heart muscle injury due to viral infections or long-term drug or alcohol use may result in CHF.

  • Conditions that overwork the heart may lead to CHF. Such conditions include: heart valve defects, high blood pressure, increased levels of thyroid hormones (thyrotoxicosis), and anemia.

  • Infiltration of the heart muscle by other tissue, as occurs with amyloidosis (accumulation of a waxy substance), may cause CHF.

  • Triggers for CHF to develop in a weakened heart include bacterial or viral infections, pregnancy or childbirth, and physical overexertion.

  • Right-sided heart failure most commonly results from left-sided heart failure.

  • CHF may result from restricted entry of blood into the heart due to thickening of the tissue surrounding the heart (pericardium), or to accumulation of excessive fibrous tissue in the heart muscle.


  • When symptoms suggest congestive heart failure, the diagnosis usually is confirmed by physical examination, patient history, and various tests to detect abnormal function of the left ventricle and/or heart valves.

  • Chest x-rays may be taken, and blood and urine tests performed.

  • Diagnostic tests may include an electrocardiogram (ECG), an echocardiogram, and cardiac catheterization. The purpose of these tests is to evaluate heart function, and to detect coronary artery disease, heart attack, and valve dysfunction.

  • In some cases exercise stress testing is used to assess the possibility of coronary heart disease. During the test, blood pressure, heart rate, ECG, and oxygen consumption rates are measured while you walk on a treadmill.

  • Electrocardiogram: measures the electrical activity of the heart. ECG abnormalities can indicate rhythm disturbances, heart muscle damage, and enlargement of the heart muscle. You may be given a portable ECG device, known as a Holter monitor, to measure the heart’s electrical activity over a 24-hour period.

  • Echocardiogram: is an ultrasound examination that produces detailed images of the heart. It can be used to detect abnormalities in the structure of the heart and to measure the ejection fraction.

  • Cardiac catheterization: may be performed in patients with angina and patients with a history of heart attack to determine if coronary heart disease is causing heart failure. This procedure produces x-ray images of the coronary arteries and the left ventricle, and can be used to monitor heart function.


You and your doctor have many options for managing heart failure. In the early stages, lifestyle measures and medications are usually all that are needed to keep symptoms under control. But as the disease becomes more severe, you may need more advanced treatments, such as an implantable device, to improve heart function.

Lifestyle measures. The first steps in the treatment of heart failure may include limits on the amount of fluids consumed (including alcohol), reductions in dietary sodium (less than 2,000 mg per day), and avoidance of caffeine, which may exacerbate heartbeat irregularities. [In addition, follow your doctor's instructions on getting regular exercise, which can help prevent symptoms from worsening.

Medications. Medications used to treat congestive heart failure include ACE inhibitors, angiotensin II receptor blockers (ARBs), beta-blockers, diuretics, and other medications. The medications your physician prescribes will depend on your specific condition, including the severity of your heart failure, its cause, and the presence of other health problems. Here's a look at the key drugs for heart failure patients:

  • ACE inhibitors and ARBs. ACE inhibitors—such as enalapril (Vasotec) and lisinopril (Prinivil, Zestril)—are the cornerstone of drug treatment for people with heart failure. ACE inhibitors promote dilation of the blood vessels and thus improve blood flow and slow the progression of CHD. They can also reduce blood pressure and lighten the workload on the heart. If you develop a bothersome dry cough while taking an ACE inhibitor, your doctor may instead prescribe an ARB, such as candesartan (Atacand) or valsartan (Diovan).
  • Diuretics and digoxin. Your physician may prescribe diuretics to reduce fluid buildup and digoxin (Lanoxin) to strengthen the heartbeat. Thiazide diuretics are effective for mild heart failure, but more potent drugs such as the loop diuretic furosemide (Lasix) are used for severe fluid retention. Spironolactone, a potassium-sparing diuretic, may be prescribed; in studies, it has been shown to substantially reduce symptoms of CHF, as well as hospitalizations for CHF and overall mortality in patients with severe CHF. People whose heart failure does not respond to a single diuretic may require a combination of several types of diuretic drugs, each with a different mechanism of action.
  • Beta-blockers. These drugs—such as carvedilol (Coreg) and metoprolol (Toprol XL)—also can decrease the workload of the heart. In an analysis of data from 17 studies, researchers concluded that the risk of death from all causes was 31% lower in patients with heart failure who were treated with beta-blockers than in those not receiving such medications. In three other large trials, carvedilol reduced deaths and total hospitalizations by up to 50% when added to standard treatment for heart failure.
  • Aldosterone blockers. Spironolactone (Aldactone) and eplerenone (Inspra) block the activity of aldosterone, an adrenal hormone that causes sodium retention. Aldosterone blockers are prescribed to individuals who develop heart failure after a heart attack, and studies show that these drugs can reduce the risk of hospitalization and death from cardiovascular disease.
  • BiDil (isosorbide dinitrate/hydralazine). This drug combination is recommended for use in people who still experience symptoms of heart failure while taking an ACE inhibitor and a beta-blocker. BiDil works by enhancing the availability of nitric oxide, which causes blood vessels to dilate. Research shows that BiDil helps improve survival in African Americans, but whether it is beneficial for Caucasians or other ethnic groups is still unknown.

Surgery. Surgery may be required to repair or replace heart valves or bypass blocked coronary arteries. Devices that help the heart to function may also be surgically implanted in the chest:

  • Percutaneous transluminal angioplasty (insertion and then inflation of a small balloon in an obstructed coronary artery via a catheter) may be performed to widen the artery and improve blood flow.
  • Heart transplant may be advised if the heart muscle has been badly damaged. The survival rate for this surgery is 80% after one year and over 60% after four years.
  • Implantable devices include CRT (cardiac resynchronization therapy), a type of pacemaker that delivers electrical impulses to improve the heart's pumping capacity or LVAD (left ventricular assist device), a mechanical pump that helps pump blood from the heart to the rest of the body.

In severe cases it may be necessary to administer oxygen through a nasal tube. Mechanical devices for administration of oxygen are available for home use after the condition has stabilized in the hospital.


  • Don’t smoke.

  • Consume no more than two alcoholic beverages a day.

  • Eat a healthy, balanced diet low in salt and fat, exercise regularly, and lose weight if you are overweight.

  • Adhere to a prescribed treatment program for other forms of heart disease.

When To Call Your Doctor

  • Make an appointment with a doctor if you regularly experience fatigue and shortness of breath after mild physical activity.

  • Call a doctor if you experience any of the following during treatment for congestive heart failure: fever, rapid or irregular heartbeat, wheezing, severe shortness of breath, or any worsening of the other symptoms of congestive heart failure.

  • EMERGENCY Call an ambulance immediately if you experience severe breathlessness.

  • EMERGENCY Call an ambulance if you experience crushing chest pain, with or without nausea, vomiting, profuse sweating, breathlessness, weakness, or intense feelings of dread. Such symptoms may indicate a heart attack.

Reviewed by Larry A. Weinrauch, M.D., Assistant Professor of Medicine, Harvard Medical School, Cardiovascular Disease and Clinical Outcomes Research, Watertown, MA. Review provided by VeriMed Healthcare Network.