Heart failure (HF), often referred to as congestive heart failure (CHF), is when the heart is unable to pump sufficiently to maintain blood flow to meet the body's needs. 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. Chest pain, including angina, does not typically occur due to heart failure.Heart failure is a common, costly, and potentially fatal condition. In 2015 it affected about 40 million people globally. Overall around 2% of adults have heart failure and in those over the age of 65, this increases to 6–10%. Rates are predicted to increase..