Heart failure (HF), often referred to as congestive heart failure (CHF), occurs when the heart is unable to pump sufficiently to maintain blood flow to meet the body's needs.The terms chronic heart failure (CHF) or congestive cardiac failure (CCF) are often used interchangeably with congestive heart failure.Signs and symptoms commonly include shortness of breath, excessive tiredness, and leg swelling.The shortness of breath is usually worse with exercise, while lying down, and may wake the person at night.A limited ability to exercise is also a common feature.
Common causes of heart failure include coronary artery disease including a previous myocardial infarction (heart attack), high blood pressure, atrial fibrillation, valvular heart disease, excess alcohol use, infection, and cardiomyopathy of an unknown cause.These cause heart failure by changing either the structure or the functioning of the heart.There are two main types of heart failure: heart failure due to left ventricular dysfunction and heart failure with normal ejection fraction depending on if the ability of the left ventricle to contract is affected, or the heart's ability to relax.
Signs and Symptoms
Heart failure symptoms are traditionally and somewhat arbitrarily divided into "left" and "right" sided, recognizing that the left and right ventricles of the heart supply different portions of the circulation. However, heart failure is not exclusively backward failure (in the part of the circulation which drains to the ventricle).
Congestive heart failure
Heart failure may also occur in situations of "high output," (termed "high output cardiac failure") where the ventricular systolic function is normal but the heart cannot deal with an important augmentation of blood volume.This can occur in overload situation (blood or serum infusions), kidney diseases, chronic severe anemia, beriberi (vitamin B1/thiamine deficiency), thyrotoxicosis, Paget's disease, arteriovenous fistulae, or arteriovenous malformations. Viral infections of the heart can lead to inflammation of the muscular layer of the heart and subsequently contribute to the development of heart failure.
Heart failure is associated with a high health expenditure, mostly because of the cost of hospitalizations; costs have been estimated to amount to 2% of the total budget of the National Health Service in the United Kingdom, and more than $35 billion in the United States. Heart failure is the leading cause of hospitalization in people older than 65.In developed countries, the mean age of patients with heart failure is 75 years old.