Nocturia refers to a need of frequent urination at night, interrupting sleep. Right ventricular failure or right sided heart failure results in fluid accumulation in gravity dependent areas, such as in legs. The fluid from the legs is returned to the bloodstream with lying at night. Patients with an underlying heart failure may experience a need of frequent urination while sleeping. Nocturia can also be a result of excess liquid intake in general cases, especially in children. Hence, it is a common but not a characteristic symptom of heart failure.

Nausea, often described as ‘motion sickness’ or ‘feeling sick’, is a discomforting sensation in the upper stomach, which often causes an urge to vomit. It is an involuntary sensation which not always, but often leads to vomiting. Heart failure in a later stage also results in fluid accumulation in the liver and intestines. This may cause nausea, which may be accompanied by abdominal pain and loss of appetite.

Edema or oedema is the abnormal accumulation of fluid in body cavity(s), producing swelling. Congestive heart failure can lead to a rise in hydrostatic pressure in the body. This results in increased secretion of interstitial fluid, which is usually accumulated in gravity dependent areas, such as legs. The abnormal fluid accumulation is, thus, reflected through swelling, particularly in the foot and ankle region. A severe case of heart failure may cause pulmonary edema (fluid accumulation in the air spaces and parenchyma of the lungs), which can result in a respiratory failure.

Ascites or hydroperitoneum, is a term used for accumulation of fluid in the peritoneal cavity (space between the abdominal cavity and abdominal wall). Longstanding failure of the left ventricular failure can lead to secondary failure of the right sided heart. This results in accumulation of fluid in the liver and intestines, which can be identified by abdominal pain and loss of appetite. Ascites is identified through swelling of the abdominal region.

Wheezing is characterized by a ‘whistling sound’ during sleep. It is caused by narrowing of the airways resulting in an abnormal sound while breathing, usually during expiration. Congestive heart failure leads to interstitial fluid accumulation in the lungs. This can further cause inflammation and spasm of the muscles in the wall of the airways, resulting in respiratory dysfunction, including wheezing. The patient may also suffer from persistent cough, especially with pink, blood-tinged phlegm.

Shortness of breath or dyspnea refers to difficulty in breathing caused by reduced supply of oxygen. Heart failure results in a weakened ability of the heart to move blood oxygen though lungs, causing fluid accumulation. This causes congestion in lungs, which further results in shortness of breath. Orthopnea refers to shortness of breath while lying flat. It is often a specific symptom of left sided heart failure. The patient may experience increased breathlessness during sleep, and may have to resort to sleeping while sitting up.

Fatigue is described as a lack of muscle strength, both physical and mental. It is identified when the body is not able to control muscle functions adequately. Fatigue is not a specific symptom of heart failure, but can be a sensitive indicator and the foremost symptom of an underlying heart disease. Patients of heart failure often experience a reduced or diminished ability to exercise. Fatigue in heart patients usually occurs with physical exertion, although in severe cases, it may even occur at rest. Patients with congestive heart failure may also experience decreased alertness and difficulty in concentrating. They may complain of weakness in the joints, especially in legs.