The Medical Definition of Congestive Heart Failure

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Congestive heart failure (CHF) is when the heart is unable to pump enough blood to meet the body’s needs. This condition typically occurs in people aged 65 and older and is often caused by other heart conditions such as coronary artery disease, untreated high blood pressure, or a heart attack.

Unlike common misperceptions about CHF, it is not a condition in which the heart stops working; rather, the heart becomes unable to pump blood sufficiently to meet the demands of the body.

woman holding heart

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What Is Congestive Heart Failure?

CHF is a condition in which the heart has trouble pumping blood through the body. It may develop over a long period of time.

The course of heart failure depends upon which anatomical part of the heart is affected. This can means:

  • The heart cannot efficiently pump enough blood to be circulated to meet the body’s needs.
  • The heart is unable to efficiently fill with blood.

Some people have both complications.

CHF is a very serious condition that can lead to severe complications or even death; it requires ongoing medical treatment.

Types of CHF include:

Having heart failure on one side of the heart predisposes a person to experience heart failure on the other side. Therefore, often a person ends up being diagnosed with heart failure on both sides of the heart. 

Classes of Congestive Heart Failure

There are several ways that CHF has been classified; health care providers usually identify each stage of heart failure according to the severity of a person’s symptoms. Using this method, the New York chapter of the American Heart Association developed a staging classification to identify the severity of the disease, including class I through IV. The classification system is called the New York Heart Association (NYHA) Functional Classification.

The categories—outlined below—are identified according to how limited a person is in performing physical activities and they include.

Classes of Heart Failure
Class I  No limitation of physical activity. Ordinary physical activity does not cause undue fatigue, palpitation, dyspnea (shortness of breath).
Class II  Slight limitation of physical activity. Comfortable at rest. Ordinary physical activity results in fatigue, palpitation, dyspnea (shortness of breath).
Class III  Marked limitation of physical activity. Comfortable at rest. Less than ordinary activity causes fatigue, palpitation, or dyspnea.
Class IV Unable to carry on any physical activity without discomfort. Symptoms of heart failure at rest. If any physical activity is undertaken, discomfort increases.

As each stage of heart failure progresses to the next stage, symptoms worsen. A person cannot go back to a previous stage once a stage determination/diagnosis is made.

Symptoms of Congestive Heart Failure

The severity and duration of heart failure symptoms depend on several factors, including the type of heart failure and perhaps most importantly, the class of heart failure one is experiencing.

Some of the most common symptoms include:

  • Shortness of breath: This may occur when a person exercises, or when resting or lying down. It occurs from fluid backing up in the lungs, which is referred to as congestion. Shortness of breath may also result from the lack of necessary oxygen-rich blood flow to the body’s cells and tissues. 
  • Dizziness, confusion, trouble concentrating and/or fainting: This is caused by a lack of oxygen-rich blood flow to the brain.
  • Fatigue: This occurs because of a lack of adequate supply of oxygen-rich blood to the major organs and muscles.
  • Diminished ability to exercise: This is due to fatigue and shortness of breath.
  • Nocturia (waking up during the night to urinate): This is caused by an excess of blood flowing through the kidneys when lying down at night; when the kidneys make more urine, it causes an increase in urination.
  • Edema (swelling): This typically occurs in the ankles, feet, lower legs, and abdomen; it is due to the body holding onto excess fluid and water, which results in edema and weight gain
  • Rapid or irregular heartbeats (also called palpitations): This occurs because of the inefficiency of the heart in its pumping action; the heart may lack the proper force to pump effectively, thereby causing the heart to speed up to provide enough oxygen-rich blood output to the body. 
  • A dry, hacking cough: This is caused by excess fluid in the lungs when pulmonary edema (fluid in the lungs) occurs because of blood flow back up.

It is important to note that symptoms of CHF, while they usually worsen over time, may come, and go. If a person with CHF no longer has symptoms, that does not mean they no longer have CHF.

Diagnosis of Congestive Heart Failure

If CHF is suspected, your doctor will make the diagnosis based on a review of your symptoms, a physical examination, blood tests, imaging tests, and other diagnostics designed to measure heart function. The failure will then be classified (see above table) by order of severity to direct the appropriate course of treatment.

A Word From Verywell

Receiving a CHF diagnosis can be overwhelming. Remember: You can live well with CHF for many years. Find support from family and friends who can help you normalize CHF. The more they understand your condition, the better able they can help you achieve your therapy goals. Try asking your doctor for a referral to a support group in your area or connect with others online through the American Heart Association Support Network.

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Article Sources
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