The heart is a muscular
organ that pumps blood throughout the body via a system of veins and arteries. Blood flows from the lungs, where it picks up oxygen, via the arteries into the heart and gets pumped out to the body, delivering oxygen to the tissues. Then, the blood returns to the heart via the veins and gets pumped back to the lungs once again completing the cycle. In order to perform these tasks, the heart itself requires large amounts of oxygen that it gets from blood.
An acute myocardial infarction (AMI) – also called a heart attack - may be caused by a blockage in the heart’s arteries that reduces or completely cuts off the blood supply to a portion of the heart. This blockage may be caused by a blood clot that gets stuck in an artery or by a thickening inside the wall of an artery that restricts the flow of blood enough to cause pain and damage. The thickening is usually caused by a build-up of fat. Symptoms may include severe chest pain, rapid pulse, breathlessness, nausea, vomiting and sweating. If you experience these symptoms,seek medical advice urgently. If medical help is not received promptly, irreversible damage to the heart muscle may occur.
The diagnosis of a heart attack, or other coronary event, may be made by changes in the electrocardiogram (ECG) and by a number of blood tests. When heart muscle is damaged, the cells release chemicals into the blood. These substances, such as CK and troponin, can be measured in blood and provide an indication of heart muscle damage.
The cardiac risk assessment can be used to predict who might be at risk for a coronary event.