Your heart has a big responsibility. It must continuously pump blood through all of your blood vessels. Heart failure develops when your heart cannot supply enough blood to your body. Sometimes this happens because the heart doesn't pump blood with enough force. It can also occur if the heart doesn't fill up with enough blood.
The heart has four chambers—two atria and two ventricles. There's one of each on each side of the heart. The right side of the heart pumps blood to the lungs. That's where your blood picks up oxygen. The blood returns to the left side of the heart, which sends the oxygen-rich blood to the body. The type of heart failure you have depends on which part of your heart is affected.
Heart failure develops over time. The heart gradually gets weaker and less able to pump blood. Usually the left side of the heart fails first.
The left side provides most of the heart's pumping power. With each contraction, it pumps blood out to the body. Between contractions, it relaxes and fills with blood. Heart failure on this side means your heart must work harder to do its job. There are two types of left-sided heart failure:
- Systolic failure: The left side of the heart doesn’t contract normally. This makes the heart unable to push enough blood out to the body.
- Diastolic failure: The left side doesn’t relax like it should. This means it can’t fill up with enough blood between each beat. This can happen if the heart muscle becomes stiff.
Right-sided heart failure often develops due to left-sided heart failure. If the left side fails, blood backs up into the lungs. This makes it harder for the right side to send blood to the lungs because of the backup. As a result, the right side has to work very hard, which eventually damages it. Once the right side is damaged, blood backs up in the body.
This type of heart failure can lead to swelling in the legs, feet and ankles. This is edema. Fluid can also get trapped in the liver, belly and digestive tract. Right-sided heart failure can also make you feel tired and short of breath.
Congestive heart failure requires timely medical attention. Congestive heart failure occurs when blood flow from the heart slows down. Blood returning to the heart backs up in the veins. The body can swell up with fluid.
Sometimes this affects the lungs. It can cause trouble breathing. You may feel short of breath, even when lying down. If not treated, congestive heart failure can lead to respiratory distress—severe trouble breathing—that can be fatal.