Congestive heart failure
), also called congestive cardiac failure
) or just heart failure
, is a condition that can result from any structural or functional cardiac disorder that impairs the ability of the heart to fill with or pump a sufficient amount of blood through the body. It is not to be confused with "cessation of heartbeat
", which is known as asystole, or with cardiac arrest, which is the cessation of normal cardiac function with subsequent hemodynamic collapse leading to death. Because not all patients have volume overload at the time of initial or subsequent evaluation, the term "heart failure" is preferred over the older term "congestive heart failure".
Congestive heart failure is often undiagnosed due to a lack of a universally agreed definition and difficulties in diagnosis, particularly when the condition is considered "mild". Even with the best therapy, heart failure is associated with an annual mortality of 10%.<1> It is the leading cause of hospitalization in people older than 65.
The symptoms depend largely on the side of the heart which is failing predominantly. If both sides are functioning inadequately, symptoms and signs from both categories may be present.
Given that the left side of the heart pumps blood from the lungs to the organs, failure to do so leads to congestion of the lung veins and symptoms that reflect this, as well as reduced supply of blood to the tissues. The predominant respiratory symptom is shortness of breath on exertion (dyspnea, dyspnée d''effort
) - or in severe cases at rest - and easy fatigueability. Orthopnea is increasing breathlessness on reclining, measured in the number of pillows required to lie comfortably. Paroxysmal nocturnal dyspnea is a nighttime attack of severe breathlessness, usually several hours after going to sleep. Poor circulation to the body leads to dizziness, confusion and diaphoresis and cool extremities at rest.
The right side of the heart pumps blood returned from the tissues to the lungs to exchange CO2 for O2. Hence, failure of the right side leads to congestion of peripheral tissues. This may lead to peripheral edema or anasarca and nocturia (frequent nighttime urination when the fluid from the legs is returned to the bloodstream). In more severe cases, ascites (fluid accumulation in the abdominal cavity) and hepatomegaly (painful enlargement of the liver) may develop.
Heart failure may decompensate easily; this may occur as the result of any intercurrent illness (such as pneumonia), but specifically myocardial infarction (a heart attack), anaemia, hyperthyroidism or arrhythmias. These place additional strain on the heart muscle, which may cause symptoms to rapidly worsen. Excessive fluid or salt intake (including intravenous fluids for unrelated indications), and medication that causes fluid retention (such as NSAIDs and thiazolidinediones), may also precipitate decompensation. Signs
In examining a patient with possible heart failure, a health professional would look for particular signs. General signs indicating heart failure are a laterally displaced apex beat (as the heart is enlarged) and a gallop rhythm (additional heart sounds) in case of decompensation. Heart murmurs may indicate the presence of valvular heart disease, either as a cause (e.g. aortic stenosis) or as a result (e.g. mitral regurgitation) of the heart failure.
Predominant left-sided clinical signs are pulmonary edema (abnormal lung sounds due to fluid accumulation), evidence for pleural effusions (fluid collection in the pleural cavity), and cyanosis (due to poor absorption of oxygen by fluid-filled lungs).
Right-sided signs are peripheral edema, ascites and hepatomegaly, an increased jugular venous pressure and hepatojugular reflux and parasternal heave.
Causes and contributing factors to congestive heart failure include the following:
Thtreatment of CHF focuses on treating the symptoms and signs of CHF and preventing the progression of disease. If there is a reversible cause of the heart failure (e.g. infection, alcohol ingestion, anemia, thyrotoxicosis, arrhythmia, or hypertension), that should be addressed as well. Reversible cause treatments can include exercise, eating healthy foods, reduction in salty foods, and abstinence of smoking and drinking alcohol.