Heart failure is usually caused by another health problem that damages the heart muscle or the blood vessels. These are the most common causes:
In coronary artery disease (CAD, also called coronary heart disease, or CHD), the arteries that supply the heart with oxygen-rich blood are too narrow. This can prevent the heart from getting enough blood, resulting in heart failure. In a heart attack, one of these blood vessels is blocked so suddenly that no blood can get through to part of the heart, and muscle tissue dies.
Constant high blood pressure can cause the blood vessels to lose their elasticity. The heart then has to work against higher resistance all the time. In order to counteract this problem and make sure that all parts of the body are supplied with blood, various changes occur in the body. For instance, the heart muscle grows larger and thicker, which increases the heart’s ability to pump blood at first. After a while, though, the muscle may harden or the heart chambers may become larger. In the long term, this can reduce the heart's ability to pump blood, eventually leading to heart failure.
Heart failure can also be caused by conditions affecting the heart muscle, the heart valves or the sac around the heart (pericardium). Examples of such conditions include inflammations, congenital heart muscle abnormalities, heart valve defects and abnormal heart rhythms like atrial fibrillation. Heart muscle tissue may also be damaged by alcohol abuse, drug abuse, or certain medications.