Heart failure, also called congestive heart failure, almost always presents as a chronic condition, although sometimes it develops suddenly, according to Medline Plus, a service of the National Institutes of Health. The heart is a muscular organ with a main function to pump blood and sustain circulation throughout the body. Heart failure indicates failing of the pumps and the resultant inadequacy of cardiac output. Several conditions may contribute to the development of chronic heart failure, with the most common cause being coronary artery disease, states Medline Plus.
Shortness of Breath
Otherwise known as dyspnea, shortness of breath is a commonly occurring symptom of heart failure. According to the American Heart Association, blood backs up from the heart into the lungs via the pulmonary vein because the left ventricle is failing to pump all of its contents towards the rest of the body. Due to the accumulating fluid in the lungs, shortness of breath or difficulty breathing occurs, accompanied by a persistent cough or wheeze that may produce frothy, white or blood-tinged mucus. Dyspnea increases when lying flat, during increased activity, and while sleeping, causing the individual to suddenly wake due to breathlessness.
Fluid Congestion
Heart failure is referred to as congestive heart failure because inadequate pumping causes fluid to back up and accumulate in other areas of the body. Besides the fluid congestion in the lungs, swelling occurs in the lower extremities and the abdomen, according to the Mayo Clinic. Swelling of the feet, ankles and legs is referred to as edema, while ascites indicates swelling of the abdomen. Another symptom is weight gain, which occurs due to generalized fluid retention.
Decreased Cardiac Output
Because the heart is not putting out enough blood supply to meet the demands of the body, the oxygen level decreases causing symptomatic fatigue and weakness. Besides shortness of breath due to fluid in the lungs, decreased oxygen is another reason for difficulty in sustaining physical exertion, even during simple activities such as walking or shopping. Since the body is not receiving the oxygen it needs, the heart recognizes this and increases its efforts despite a failing pump, causing a sensation of palpitations and "racing." Decreased blood supply to the digestive system can cause decreased appetite and nausea due to slowed motility of the gastrointestinal tract. Other symptoms of chronic heart failure include confusion, decreased mental alertness and difficulty concentrating, states the Mayo Clinic.
