A heart is a muscle, and it needs a good blood flow to keep it healthy. As we get older, the smooth inner walls of the arteries (like pipes) that supply the blood to your heart muscle can become damaged and narrow due to the build up of fatty materials, called ‘plaque’. Plaque is mostly made of cholesterol.
When an area of plaque cracks, blood cells and other parts of the blood stick to the damaged area and form blood clots. A heart attack occurs when a blood clot completely blocks the flow of blood and seriously reduces blood flow to the heart muscle. As a result, some of the heart muscle starts to die.
The longer the blockage is left untreated, the more the heart muscle is damaged. If the blood flow is not restored quickly, the damage to the heart muscle is permanent.