Edema is the clinical term for swelling caused by fluid retention. It can be triggered by any number of injuries, illnesses, or health conditions. But among the more serious conditions that can cause edema is heart failure.

This happens when the heart muscle weakens and can no longer pump enough blood to meet the body’s needs. It can also happen if the pressure is increased, forcing the fluid to back up into the legs or abdomen, or when a leaky heart valve causes fluid retention.

Proper treatment of heart failure, or whatever is causing your edema, should help relieve your swelling and other symptoms. In this article, we’ll look more at why heart failure causes edema, as well as other types of edemas, and current treatment options.

Although it sounds like the heart is failing to work at all, the term heart failure really means that the heart has grown weaker or stiffer. It still pumps blood, but it’s not enough to meet the body’s needs.

Heart failure can result from several issues, including:

Diseases like diabetes and sleep apnea can also weaken the heart.

Since the heart isn’t able to adequately pump blood out through the arteries and bring it back through the veins, blood can begin to pool, especially in the legs and feet.

The veins require a certain amount of force from the heart to keep blood flowing up to the heart and lungs, where it receives oxygen and other nutrients. The pressure inside the veins is also higher due to higher pressures in those with heart failure.

Without medications or devices to improve the heart muscle’s strength, blood doesn’t circulate properly in someone with heart failure. Excess blood and other fluids in the capillaries can leak out into bodily tissues, causing edema.

Sometimes edema is the first sign of heart failure. Once heart failure is diagnosed, it becomes important to monitor increases in body weight that may result from increased fluid retention.

One 2021 review of studies suggests that increases in edema may also predict worsening heart failure.

Fluid buildup in the feet and legs, known as pedal edema, is a common early sign of heart failure. But there are other types of edema that may be the result of heart failure, including:

  • Peripheral edema: swelling of the the hands or lower legs.
  • Pitting edema: swelling in the feet, legs, or anywhere else. Pitting edema gets it name because it leaves a “pit” or dent in the skin on the affected area.
  • Pulmonary edema: a buildup of fluid in the lungs.

There are three main types of heart failure. Each one reduces the heart’s ability to pump effectively.

Left-sided heart failure

The left side of the heart is responsible for pumping blood out of the heart to the rest of the body. Left-sided heart failure can develop when the left ventricle (lower left chamber of heart) can no longer pump enough blood out of the heart and into circulation.

It can also occur when the left ventricle becomes too stiff and can’t fill with enough blood in between heart beats. This keeps the heart from meeting the body’s requirements for oxygenated blood. Left-sided heart disease sometimes involves edema in the lungs.

Right-sided heart failure

When blood returns to the heart, it enters the right atrium (top right chamber) and then moves to the right ventricle (bottom chamber), which pushes blood into the lungs to receive oxygen.

When the right side of the heart weakens, blood coming in from the veins can start to back up. This is called right-sided heart failure, which usually results in edema in the lower extremities.

Congestive heart failure

The term congestive heart failure is often used interchangeably with heart failure. But it really just refers to a state of heart failure in which fluid buildup in the body is serious enough to require medical attention. In this instance, “congestion” is another word for fluid. This can result in both pulmonary edema and edema of the abdomen, lower legs, and feet.

Treating edema usually means treating the underlying cause of the swelling. In the case of heart failure, that could involve the use of medications like:

  • diuretics to reduce fluid levels in the body
  • medications like ACE inhibitors and ARBs or ARNI to help the blood vessels relax, so circulation is a little easier
  • beta blockers and ivabradine to reduce the burden on the heart
  • mineralocorticoid receptor antagonists (MRAs)
  • SGLT2 inhibitors

In very serious cases, implantable pumps or defibrillators are needed to help the heart muscle keep up with the body’s demand for blood. And in the most severe cases of heart failure, a heart transplant may be necessary.

Treating the edema itself may include:

  • compression stockings to help increase the pressure in your lower legs, which may help push blood up to the heart
  • exercise to get the leg muscles affected by edema working harder and pumping blood back to the heart
  • elevating your legs or other swollen part of the body above the heart to help keep blood returning to the central circulation.

Edema is a common symptom of heart failure, but it can also be caused by other conditions.

With heart failure, fluid builds up because the body’s circulatory system isn’t operating as strongly as it normally would. This is due to a weakening or stiffening of the heart muscle.

If you notice swelling, but know of no underlying medical reason for it, see a doctor soon. Even if the cause isn’t heart failure, you’ll want to know why the swelling has developed and how it can be treated or prevented in the future.