The pumping action of the heart is caused by contraction of the muscles within the heart wall. These muscle contractions are caused by electrical activity within the cells. In order for the muscles to work they must receive an adequate supply of oxygenated blood, which is delivered via vessels known as the coronary arteries.
Over times fatty deposits (atheroma) can build up on the inside of the arteries causing them to become progressively narrower until they eventually block the flow of blood altogether. Widespread fatty deposition is known as coronary atherosclerosis. The blocked arteries are said to be occluded and the blockage is known as a coronary thrombosis. Blood can not flow beyond the coronary thrombosis and the muscle past that point becomes starved of oxygen and dies. If a sufficiently large area of muscle dies the heart can stop beating altogether. This process is commonly referred to as a heart attack. Less severe muscle damage may result in the electrical activity of the heart becoming uncoordinated - a condition known as ventricular fibrillation.
People experiencing a heart attack often complain of a band of crushing pain around their chest, which often radiates to their lower jaw and upper arms. Unlike angina the pain will not subside if they rest. Their skin is usually pale, cold and clammy and their pulse irratic and weak. If you recognise these symptoms you must get medical help immediately.
Jargon Buster:
Over times fatty deposits (atheroma) can build up on the inside of the arteries causing them to become progressively narrower until they eventually block the flow of blood altogether. Widespread fatty deposition is known as coronary atherosclerosis. The blocked arteries are said to be occluded and the blockage is known as a coronary thrombosis. Blood can not flow beyond the coronary thrombosis and the muscle past that point becomes starved of oxygen and dies. If a sufficiently large area of muscle dies the heart can stop beating altogether. This process is commonly referred to as a heart attack. Less severe muscle damage may result in the electrical activity of the heart becoming uncoordinated - a condition known as ventricular fibrillation.
People experiencing a heart attack often complain of a band of crushing pain around their chest, which often radiates to their lower jaw and upper arms. Unlike angina the pain will not subside if they rest. Their skin is usually pale, cold and clammy and their pulse irratic and weak. If you recognise these symptoms you must get medical help immediately.
Jargon Buster:
- Coronary arteries: The small arteries that supply oxygenated blood to the heart muscle.
- Atheroma: Fatty deposits within an artery which cause it to become occluded.
- Coronary atherosclerosis: The condition where atheroma has built up on the inside of the coronary arteries.
- Occlusion: Narrowing of the arteries to such an extent that blood is unable to flow.
- Coronary thrombosis: An occlusion of the coronary artery.
- Myocardial infarction: The region of heart muscle beyond the coronary thrombosis which is starved of oxygen and dies.
- Ventricular Fibrillation: The condition where the electrical activity of the heart becomes uncoordinated and the heart muscles contract irregularly.
