What is a heart attack?
Heart Attack – Damage to the heart caused by a blockage in one of the arteries that supplies the heart muscle. Blockage of one of these arteries “coronary arteries” reduces the blood flow to the heart muscle and can cause chest pain or “angina”. When a blood clot forms at the site of a blockage it can completey block the flow of blood to the portion of the heart muscle it supplies and this is what causes an actual heart attack or “myocardial infarction”. If blood flow i s not restored there is irreversible damage to the heart mucle. Therefore it is imperative that a heart attack is treated as quickly as possible. Fortunately, there is excellent medical and catheter based therapies to treat heart attacks. Therefore, it is critical to call 911 at the earliest sign of a heart attack.
Various factors may cause a cholesterol plaque in the coronary artery to become unstable and rupture into the channel of the artery, exposing the fatty contents of the plaque to the circulating blood. When blood comes in contact with this fatty material, rapid clotting of the blood occurs. If the blood clot is large enough, it can completely occlude the channel of the coronary artery and prevent any blood from supplying the portion of heart muscle supplied by that particular artery. Since heart muscle cells can survive only minutes to hours without oxygen, occlusion of the coronary artery results in death of part of the heart muscle–a heart attack. It is important to understand that the likelihood that a cholesterol plaque will rupture does not depend on the degree of narrowing that plaque causes. A plaque forming a 20% narrowing, 50% narrowing, or 90% narrowing are all capable of rupturing and causing a heart attack. This explains how a “minor” plaque which does not cause any symptom
You have a heart attack when blood can’t get to your heart. This happens when one of the vessels that takes blood to your heart is suddenly blocked. If your heart doesn’t get the blood it needs, part of it dies. You might be able to tell you’re having a heart attack. You might feel severe pain in your chest that can spread down your arms. If you think you’re having a heart attack, call 911 at once. No one will blame you if it’s a false alarm. If it is a heart attack, every minute counts. At the hospital, doctors can run tests and treat you right away. Acting quickly could save your life. Source: Agur AMR, Lee MJ, Grant JC. Grant’s atlas of anatomy. 10th edition. Lippincott Williams and Wilkins, Philadelphia, U.S.A.; 1999. 1 Key points about heart attacks • A heart attack is life threatening, but treatment can help you get through it. • Most treatments work best if you get them quickly. If you think you’re having a heart attack, call 911 right away. • The first thing doctors will do is
–> The heart works 24 hours a day, pumping oxygen- and nutrient-rich blood to the body. Blood is supplied to the heart through its coronary arteries. In coronary heart disease (CHD), plaques or fatty substances build up inside the walls of the arteries. The plaques also attract blood components, which stick to the artery wall lining. Called atherosclerosis, the process develops gradually, over many years. It often begins early in life, even in childhood. The fatty buildup or plaque can break open and lead to the formation of a blood clot that seals the break. The clot reduces blood flow. The cycle of fatty buildup, plaque rupture, and blood clot formation causes the coronary arteries to narrow, reducing blood flow. When too little blood reaches the heart, the condition is called ischemia. Chest pain, or angina, may occur. The pain can vary in occurrence and be mild and intermittent, or more pronounced and steady. It can be severe enough to make normal everyday activities difficult. Th
A heart attack (also called myocardial infarction) is when part of the heart muscle is damaged or dies because it isn’t receiving oxygen. Oxygen is carried to the heart by the arteries (blood vessels). Most heart attacks are caused by a blockage in these arteries. Usually the blockage is caused by atherosclerosis, which is the buildup of fatty deposits (called plaque) inside the artery. This buildup is like the gunk that builds up in a drainpipe and slows the flow of water. Heart attacks can also be caused by a blood clot that gets stuck in a narrow part of an artery to the heart. Clots are more likely to form where atherosclerosis has made an artery more narrow.
