Orthopnea Causes and Symptoms

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Orthopnea is the name doctors use for the symptom of dyspnea (shortness of breath) that occurs when a person la lying flat. Orthopnea is considered an important symptom mainly because it is often a sign of worsening heart failure, but it can also be caused by other medical conditions. For this reason, anyone who experiences orthopnea should always be evaluated by a physician.

What Causes Orthopnea?

When anyone lies down flat, gravity causes a redistribution of fluid within the body. Typically, some of the fluid in the lower part of the body, particularly the legs and the organs of the abdomen, gravitates into the chest area. This redistribution of fluid is normally quite minor, and in most people it has no effect whatsoever on breathing.

However, in people with congestive heart failure, the heart may be unable to accommodate this extra fluid, and cannot perform the additional work necessary to keep this extra fluid from accumulating in the lungs. As a result, pulmonary congestion — and early pulmonary edema — may occur, and shortness of breath results. In addition to the dyspnea, some people will also experience coughing or wheezing when lying down. These kinds of breathing difficulties caused by assuming the recumbent position are referred to as orthopnea.

When a person experiences orthopnea, sitting up or elevating the head reverses some of the fluid redistribution that has occurred, and relieves the pulmonary congestion. Symptoms typically are rapidly improved simply by changing position.

Heart failure is not the only cause of orthopnea, but it is by far the most common cause. Sometimes people with asthma or chronic bronchitis will have more breathing problems while lying down. The symptoms of wheezing and shortness of breath that occur with these conditions, however, usually do not disappear as quickly after sitting up, but take more time to resolve. Sleep apnea can also produce symptoms similar to orthopnea, or more often, to paroxysmal nocturnal dyspnea (mentioned in the next section).

Related Symptoms

Another symptom strongly associated with heart failure is paroxysmal nocturnal dyspnea, or PND. PND is also related to fluid redistribution that occurs during sleep, but it is a more complex condition than “simple” orthopnea. Generally, people who have PND do not notice dyspnea right after lying down. Rather, they are awakened from sleep with an episode of severe shortness of breath that causes them to immediately sit up for relief. In addition to dyspnea, patients with PND also often experience palpitations, severe wheezing, and a sense of panic.

Clearly, PND is a far more dramatic event than orthopnea. It is thought that some additional mechanism (aside from simple fluid redistribution) is present in people with PND, perhaps related to changes in the brain’s respiratory center that may be associated with heart failure.

Recently, doctors have recognized another kind of symptom in people with heart failure that is also related to fluid redistribution — “bendopnea,” or dyspnea caused by bending over.

Evaluating Orthopnea

Doctors should routinely ask any patient with heart failure or suspected heart failure whether they experience any dyspnea upon lying down. This is an important question because worsening orthopnea often indicates an underlying deterioration in cardiac function.

Many people with orthopnea deal with the symptom subconsciously by adding a pillow or two. They may not even realize that they get short of breath when lying flat — they may just feel more comfortable with their heads elevated. This is why doctors will often ask how many pillows a patient with heart failure is using, and will record the answers in the chart as “two-pillow orthopnea” or “three-pillow orthopnea.”

Because worsening orthopnea is often an early sign of worsening heart failure, anyone with heart failure (and their significant others) should pay attention to worsening symptoms, and even to the number of pillows they are using. Early intervention when symptoms are relatively mild can avoid a heart failure crisis, and prevent the need for hospitalization.

A Word From Verywell

Orthopnea is one of the many manifestations of pulmonary congestion that can occur in people with heart failure. The onset of orthopnea, or changes in the severity of orthopnea, can indicate important changes in the severity of heart failure. So, anyone who has heart failure should pay attention to this symptom.

View Article Sources
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  • Thibodeau JT, Turer AT, Gualano SK, et al. Characterization of a Novel Symptom of Advanced Heart Failure: Bendopnea. JACC Heart Fail 2014; 2:24–31. 
  • Yancy CW, Jessup M, Bozkurt B, et al. 2013 ACCF/AHA Guideline for the Management of Heart Failure: Executive Summary: a Report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines. Circulation 2013; 128:1810.