Heart failure is the medical term used to indicate the presence of a weak heart. This term refers to the heart's inability to circulate blood through the body. Blood flow is slower than normal, which places more pressure on the heart than usual. Slower blood circulation means body's cells don't receive the oxygen and nutrients needed for normal function. This added pressure on the heart causes its chambers to thicken, or the heart will expand so it can hold more blood. If this condition persists, the muscles that make up the walls of the heart will weaken.
A number of conditions can cause, or contribute, to a weak heart. Disorders that overwork the heart muscles, like high blood pressure, thyroid disease, kidney disease or diabetes can cause it to gradually deteriorate over time.
Coronary artery disease (CAD)--a condition brought on by a narrowing of the arteries--is another condition that causes the heart to work harder than normal. Narrow arteries prevent needed oxygen and nutrients from reaching the heart. In addition, the heart has to exert extra force to move blood through these narrowed passage ways.
The symptoms associated with a weak heart are fairly easy to spot. Cells that don't receive sufficient blood flow begin to break down from a lack of oxygen and nutrients. When this happens, fluids contained inside the blood vessels begin to seep into surrounding tissues. This can cause swelling in the ankles and legs, and water retention throughout the body. Excess fluids can also accumulate in the lungs and digestive track, causing shortness of breath and a loss of appetite. The heart's inability to circulate blood to the muscles leaves the body feeling tired and weak, making everyday tasks harder to do.