Heart failure occurs when the heart muscle is weakened and cannot pump enough blood to meet the body’s needs for blood and oxygen.
The most common conditions that can lead to heart failure are coronary artery disease, high blood pressure and previous heart attack.
Coronary artery disease (CAD) develops when the arteries that supply blood to heart muscle become hardened and narrowed. This is due to the buildup of cholesterol and other material, called plaque, on their inner walls, a process called atherosclerosis. As the plaque grows, it blocks the blood flow through the arteries. As a result, the heart muscle can’t get the blood or oxygen it needs. This can lead to chest pain (angina) or a heart attack. Most heart attacks happen when a blood clot suddenly cuts off the hearts’ blood supply, causing permanent heart damage. Over time, CAD weakens the heart muscle and contributes to heart failure.
High blood pressure makes your heart work harder to push blood round your body. To cope with this extra effort, your heart becomes thicker and stiffer, which makes it less able to do its job. Over time, the added strain weakens the heart and leads to heart failure.
In persons who have suffered a heart attack, one of the arteries supplying their heart muscle has become completely blocked, cutting off the blood supply. Oxygen and nourishment are unable to reach that part of their heart muscle, causing it to die. Their remaining healthy heart muscle has to pump harder to compensate, putting more workload onto their heart than it can handle. Over time, this can lead to heart failure.