With heart failure, blood moves through the heart and body at a slower rate, and pressure in the heart increases. Therefore, the heart cannot pump enough oxygen and nutrients to meet the body's needs. The chambers of the heart respond by stretching to hold more blood to pump through the body or by becoming thicker and stiffer. This helps to keep the blood moving for a short while, but then the heart muscle walls weaken and are not able to pump as strongly. The heart muscle walls are damaged and do not pump or fill normally. The kidneys often respond by causing the body to retain fluid (water) and sodium.

If fluid builds up in the arms, legs, ankles, feet, lungs or other organs, the body becomes congested; congestive heart failure is the term used to describe this condition.

• Shortness of breath or difficulty breathing with exercise, at rest or when lying flat in bed. Shortness of breath occurs when fluid backs up into the lungs (congestion) or when your body does not have enough oxygenated blood to allow you to continue your activity or exercise without a rest period. Even though you think of shortness of breath as a lung problem, it is your heart condition that causes episodes of shortness of breath. In some cases, these symptoms may cause you to wake up suddenly at night, disrupting your normal sleep patterns.
• A dry, hacking cough or wheezing.
• Swollen ankles, legs and abdomen and weight gain. Less blood to the kidneys causes fluid and water retention, resulting in edema (swelling) and water weight gain.
• Need to urinate while resting at night. Another symptom may include an increased need to urinate during the night.
• Tiredness (fatigue) and weakness during exercise or activities occur because the heart is not pumping enough oxygen-rich blood to major organs and muscles.
• Dizziness, confusion, difficulty concentrating or fainting may occur because the heart is not pumping enough oxygen-rich blood to the brain.
• Rapid or irregular heartbeats (palpitations): When the heart muscle does not pump effectively, the heartbeat speeds up to help the heart get enough oxygen-rich blood to major organs and muscles. An irregular heartbeat can occur from many problems, including an enlarged heart, not enough oxygen-rich blood to the heart muscle, and too much volume or pressure in the heart. In addition, heart failure causes the electrical conduction system in the chambers of the heart to be irritable, leading to irregular heartbeats.
• Other symptoms include a feeling of fullness (bloating) in your stomach, loss of appetite or nausea.

If you have heart failure, you may have one or all of these symptoms. Sometimes, people with heart failure do not have any symptoms.

Oxygen-rich blood then returns to the left side of the heart. The blood flows from the left upper chamber (left atrium) to the lower chamber (left ventricle) through the open mitral valve. From the left ventricle, the blood is pumped into a network of arteries (blood vessels) that carry the blood throughout the body.

With systolic heart failure, the left ventricle’s pumping power is weaker than normal, causing less blood to move from the heart to the body. Less blood flow to main organs and tissues of the body can cause symptoms, as described on the first page.

Systolic left ventricular dysfunction (or systolic heart failure) occurs when the left ventricle heart muscle doesn’t contract with enough force, so less oxygen-rich blood is pumped throughout the body.

Heart failure with preserved left ventricular function (diastolic heart failure) occurs when the heart contracts normally, but the ventricles do not relax properly or are stiff and less blood enters the heart during normal filling.

A test called the ejection fraction (EF) is used to measure how well your heart pumps with each beat to determine if systolic dysfunction or heart failure with preserved left ventricular function are present. Ejection fraction is the measurement of how much blood is being pumped out of the left ventricle of the heart. Heart failure can occur due to a weakened heart muscle (systolic heart failure) or may be related to a stiff, inflexible heart muscle (diastolic heart failure). In diastolic heart failure, the ejection fraction can be normal, but the stiff heart muscle causes increased pressures inside the heart and lungs, leading to symptoms. Your doctor can discuss which condition is present in your heart. A number of different tests are used to define which kind of Heart Failure you suffer from.

Heart failure in women is often linked to high blood pressure, coronary artery disease, valve disease and diabetes. Although the signs and symptoms of heart failure are the same among men and women, women tend to have more symptoms of exercise difficulty and shortness of breath than do men. Women also experience ankle swelling more frequently than do men.