An Overview of Heart Failure

Doctor talking to patient about heart failure
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"Heart failure" and "congestive heart failure" are two terms that mean nearly the same thing. And, in fact, most doctors use them interchangeably.

Heart Failure

Heart failure is the condition in which the heart is unable to perform the work necessary to keep up with the body's needs. It can be the end result of many different types of heart disease, including coronary artery disease, heart valve diseases such as aortic stenosis, cardiomyopathy (weakness of the heart muscle), and even cardiac arrhythmias.

Also, heart failure can produce a range of symptoms. These may include dyspnea, edema (swelling, usually in the legs and ankles), weakness and fatigue, and lightheadedness. But in most people with heart failure, the dyspnea and edema are the most prominent symptoms and these are the symptoms doctors usually focus on when they treat a person with heart failure.

The dyspnea and edema are caused by the generalized fluid accumulation that tends to occur with heart failure. This fluid accumulation, or “congestion,” tends to be most prominent in the lungs and the lower extremities.

Congestive Heart Failure

The term "congestive heart failure” simply acknowledges that lung congestion, and the dyspnea that results from it, is often the most prominent symptom experienced by people who have heart failure. And, since this lung congestion occurs to some extent in the large majority of patients with heart failure, most people with heart failure can be said to have congestive heart failure.

This is why "heart failure" and "congestive heart failure" are considered virtual synonyms by most doctors.

The dyspnea that occurs with congestive heart failure often manifests itself with physical exertion but may occur primarily when lying down (a symptom called orthopnea) or it may occur suddenly in the middle of sleep (a condition called paroxysmal nocturnal dyspnea or PND).

In recent years doctors have recognized a “new” symptom of congestive heart failure called “bendopnea,” that is, dyspnea when bending over.

Low Output Heart Failure

Occasional patients with heart failure may have little or no lung congestion. In these patients, the main problem tends to be that the heart muscle has become so extremely weak that the heart is no longer able to pump enough blood to the body's organs.

The most prominent symptoms experienced by these individuals tend to be caused by dangerously low blood pressure—namely, extreme weakness, severe fatigue, and episodes of lightheadedness or syncope.

People whose heart failure manifests predominantly with these symptoms are often said to have "low output heart failure,” in distinction from congestive heart failure. Low output heart failure is usually a sign of very advanced heart failure, and people with this condition often have a very poor prognosis.

A Word From Verywell

For the most part, the terms "heart failure" and "congestive heart failure" refer to the same condition. So, to be clear, your doctors are saying the same things about your cardiac condition.


McMurray JJ, Adamopoulos S, Anker SD, et al. ESC Guidelines for the Diagnosis and Treatment of Acute and Chronic Heart Failure 2012: The Task Force for the Diagnosis and Treatment of Acute and Chronic Heart Failure 2012 of the European Society of Cardiology. Developed in collaboration with the Heart Failure Association (HFA) of the ESC. Eur Heart J 2012; 33:1787