If you find yourself feeling excessively tired during the day along with other symptoms, it could indicate heart failure (per AHA). One common symptom is shortness of breath. When the heart cannot keep up with the blood supply needed by the body, fluid can accumulate in the lungs. This fluid can make it difficult for you to breathe properly and trigger persistent coughing or wheezing. Sometimes, this can happen suddenly at night and disturb your sleep.
People with heart failure may experience edema, which can cause swelling in different parts of the body, like the feet, ankles, legs, fingers, and abdomen, and may also be accompanied by weight gain. Healthline states that edema happens because the heart is unable to adequately pump blood, which can cause blood to accumulate in veins and lead to the release of fluid from blood vessels into other tissues. You might have digestive problems, such as feeling full or nauseous, because of insufficient blood supply to the digestive system. You may also experience an increased heart rate or heart palpitations as your heart tries to compensate for its reduced pumping capacity. Additionally, changes in certain substances, such as sodium in the blood, can lead to reduced blood flow to the brain, which can cause confusion, memory loss, and disorientation.