A heart attack (myocardial infarction or ‘coronary’) refers to damage to the heart caused when the blood supply to part of the heart muscle is blocked. A heart attack happens because the blood supply has been cut off following a blockage in a branch of one of the coronary arteries (the blood vessels which supply the heart muscle).
This is usually the result of 2 processes: the development over many years of fatty plaques in the walls of the arteries and the formation of a clot on one of the plaques.
Treatment given early during a heart attack can help to dissolve the clot, reducing damage to the heart muscle.
The process that leads to the narrowing and blockage of the coronary arteries (atherosclerosis) starts as early as adolescence and builds up slowly over the years. No single cause of coronary artery disease has been identified. There are, however, several things that are known to increase the risk of a heart attack.
These are called risk factors. The more risk factors you have, the greater your chance of having a heart attack. However, science has not revealed all the factors leading to coronary artery disease, so some people have a heart attack without having currently recognised risk factors.
Blood cholesterol and triglycerides are best measured as part of an overall assessment of your risk of heart disease. They can be measured by a simple blood test, which can be arranged by your doctor. Ideally, if you are at high risk of heart disease, a total blood cholesterol level of less than 4.0 mmol/L is desirable, although any reduction in high cholesterol would be of benefit. Ask for further advice from your doctor. The key points are to:
People with diabetes have a greater chance of developing heart disease than those who don't have diabetes. Diabetes can affect the vessels that supply blood to the heart. Working with your doctor to develop a plan to control your diabetes is the first step in safeguarding your heart.
Many of the lifestyle changes suggested for keeping your heart healthy (such as a good diet and regular exercise) are important in controlling diabetes. Sometimes medication is needed. Ask your doctor.
Active people have fewer heart attacks and have a better chance of recovery than inactive people. They also feel good, are less tired, more relaxed and are better able to cope with stress. You can do more with less effort, have better heart function and possibly lower blood pressure. Regular activity helps control weight and lower blood cholesterol levels.
Aim to accumulate 30 minutes of physical activity most days of the week. You don't have to join a gym or pound the pavements all day long. Regular brisk walking for half an hour can do the job just as well. Find a variety of activities you enjoy. Look for opportunities to put activity in your day. Every bit helps. Two or 3 sessions that add up to half an hour are OK if you can't do it all at once.
High blood pressure can enlarge and weaken the heart. It also damages the blood vessels. If they become narrow or blocked, it may result in a heart attack or stroke. Get your blood pressure checked regularly, particularly as you get older, or if you are taking any medication (including the contraceptive pill), if you are overweight, have diabetes or a family history of heart disease.
If you smoke, your chances of a heart attack are 2 or 3 times more than for a non-smoker, and you have a higher risk of stroke and many other diseases. Lifetime smokers have a one in 2 chance of dying from smoking-related diseases and shorten their lives by an average of 14 years.
Smoking also affects the health of others around you. If you stop smoking, all the risks mentioned above soon become much less.
Although it is now clear that factors such as heredity and lifestyle are the primary problems, a person's response to stress may also contribute to their risk of heart disease. It is advisable for general health and well-being to understand what things stress us unduly, and to find ways of dealing with them. Here are some tips to keep stress under control.
Last Reviewed: 17 March 2003