Factors Affecting the Development of Coronary Heart Disease.

Factors Affecting the Development of Coronary Heart Disease

Heart is a muscle, like any muscle it requires a constant supply of nutrients such as oxygen and glucose to function. These nutrients are carried to the heart via the coronary arteries. Coronary heart disease (CHD) is the narrowing and clogging up of these arteries.

If the coronary arteries get partly blocked, it causes the part of the heart which it was supplying, to respire anaerobic ally due to lack of oxygen, lactic acid is produced, causing the muscle cells to get cramp. This cramp is associated with chest pains called angina, which is relieved by rest. If the coronary arteries become fully blocked the part of the muscle which the arteries where supplying dies, this is called a heart attack or myocardial infarction. Both of these forms of heart disease occur due to narrowing or clogging up of the coronary arteries bought about as a result of arteriosclerosis. 'Arteriosclerosis, or hardening of the arteries is the disease process which leads to CHD’ (biological sciences review) some hardening is thought to occur due to old age and hence older you are the higher the chance there is for you to develop heart disease.

But 'many scientists think that arteriosclerosis begins with damage to the innermost layer of the artery wall' (www.americanheart.org) possibly bought about by a blow to the chest for example, harmful chemicals like carbon monoxide (found in tobacco smoke), high blood pressure or damaged caused by high levels of cholesterol (LDL). Once damaged fatty materials and other substances get absorbed and deposited in the artery wall this mass of fat-laden cells is called a atheroma. Muscle fibres grow into the atheroma to produce a plaque; this grows and narrows the artery (a process which can take several years) this eventually grows so big that it tears the endothelium bringing a clot to area. This clot can get blocked in small arteries (embolism).

Cholesterol in the form of lipoprotein is transported through the body in several ways; 'excess low-density lipoproteins (LDL) can infiltrate the walls of blood vessels. High levels of LDL cholesterol are directly linked to the formation of arteriosclerosis and heart disease' (biological sciences review). LDL's can accumulate in dangerous amounts and the obvious solution seems to be, have less cholesterol in our diets since its so easily measured, but a lot of people inherit a dominant gene which causes a person to permanently have high levels of cholesterol, its called familial hypercholesterolaemia. 85 % People with this disease have a heart attack in their life and 50% of those people die.

Smoking promotes the development of arteriosclerosis because it contains harmful chemicals, which damage the endothelial layer of the artery which starts of the arteriosclerosis reaction. It causes platelets in the blood to stick together, this is something, which is said to be prevented by talking aspirin (the guardian), and Platelets sticking together can eventually get clogged up in a narrow artery. Smoking is also said to increase the blood cholesterol level as well as increasing blood pressure due to tobacco smoke containing nicotine, which is a vasoconstrictor. Overall you are four times more likely to develop heart disease if you smoke than if you don't smoke due to all of its effects.

High Blood pressure promotes heart disease because the blood vessels in our body respond to the change in pressure by increasing the thickness of its walls; this causes further increases in pressure by decreasing the size of the lumen. This vicious circle leads to blood pressure being so high that it damages the endothelial layer, increasing the chance of developing an atheroma.

Lack of exercise keeps the heart healthy and blood pressure down. Obesity can lead to heart disease due to the excess fat adding strain to the heart. When high blood pressure co-exists with obesity and diabetes the chance of developing heart disease is several times higher. This is particularly a problem the USA where there are 4000 heart attacks every day and 500 000 people die every year.

Heart disease is the biggest single cause of premature death in Britain and it costs the government around £13 million a year.

BIBLIOGRAPHY

'FACTORS AFFECTING THE DEVELOPMENT OF CORONARY HEART DISEASE'

When coronary arteries, which supply the heart muscle with blood and oxygen, become partially or completely blocked a person has coronary artery disease. When the heart muscle is damaged as a result of this blockage then the person has developed coronary heart disease. This can lead to a heart attack, angina (chest pains) or as in 20% of cases sudden death. Coronary Heart disease is, by far, the leading scourge and cause of death in the developed world.

The narrowing of the arteries results from the complicated interaction of many systems within the body. It is believed that this process begins even before we are born; researchers have established that arteriosclerosis (the process that leads to narrowings) can begin in the first year of life. Once the process has begun the narrowing grows unevenly over time. For example, it can grow slowly for decades, and then suddenly increase its growth rate. As the narrowing grows, it increasingly limits the flow of blood through the artery. Chest pains occur when the heart requires more blood than can flow through the narrowing this is called angina pectoris. A heart attack is a sudden event that occurs when blood flow through an artery is completely blocked, heart attacks however are not usually caused by a gradual narrowing of an artery they are usually caused by a blood clot forming at the site of a narrowing.

So it is established that the development of coronary heart disease can start early on in life and grows progressively until the problems mentioned above occur. However there are factors that affect the rate at which development occurs, and explain why age, wealth, family history, lifestyle and the country you live in affect your chance of developing the disease.

If a member of your immediate family has coronary heart disease then your risk of someday developing it is twice as high than normal. The risk is even higher if the relative developed coronary disease at an early age (before 55 in men and 65 in women). This is a general rule in genetics that the earlier in life the disease occurs, the greater the influence of genes. As with most common diseases, coronary heart disease results from an interaction of genes and the environment, so the lifestyle you lead works with or against the genetic trait. So if you are in a high-risk category because of family links with the disease then smoking or being overweight will only help any genetic trait in the direction of disease.

Studies of twins provide the clearest evidence for genes and environment both having a role. In 1994 researchers looked at 21,000 twins born in Sweden between 1886 and 1925. They found 2367 pairs in which at least one twin had died of coronary heart disease.

If coronary disease were governed only by genes, then every time one identical twin died of it, the other would have to as they both have the same genes. So the concordance rate should be 100%. The table shows however, that instead of 100% concordance there is only 30% concordance between identical twins. This shows that coronary disease has an environmental component.

If coronary disease were purely an environmental condition, then genes should make no difference at all. The concordance rate would be the same for identical twins and non-identical twins. However the concordance rate is significantly higher in identical twins (30%) than non-identical (20%). This shows that coronary disease has a strong genetic component.

The study also looked at the importance of age. They considered a hypothetical man who died of coronary disease before 65. Statistically they found his identical twin would be 3 times more likely to die of coronary disease than a non-identical twin would be. This shows a powerful genetic factor, for women in the same situation the risk to the identical twin would be 6-7 times greater than a non-identical twin would face. Therefore the genetic factor leads to coronary disease at a relatively young age.

Diet is one such environmental issue that affects the development of coronary disease. In your blood three types of cholesterol affect the coronary heart condition: - low-density lipoproteins (LDLs), high-density lipoproteins (HDLs), and very-low-density lipoproteins (VLDLs).

LDLs are considered to be the bad cholesterol molecules as they can accumulate on the walls of your arteries, forming plaques causing arteriosclerosis. This only occurs if LDL particles are in excess and therefore stay in the blood. If LDL receptors do not receive the LDL particles or there are to few of them then they are not broken down in the liver and so they are deposited on the artery walls. HDL picks up excess LDL and takes it to the liver to be disposed of so a higher concentration of HDL than LDL is good. Eating too much fat from dairy products, meats and hydrogenated oils causes high LDL levels.

It is argued however that this theory does not sufficiently explain moralities. It is found that 80% of individuals who develop coronary disease have the same cholesterol values as those who do not develop it. Thus blood cholesterol values cannot accurately indicate whether you are safe or not.

Smoking is now known to be bad for a person's health it can lead to lung cancer, throat cancer and contributes to coronary disease. After smoking a cigarette, your heart rate increases 15 to 30 beats per minute and your blood pressure increases as well, increased blood pressure can damage the artery walls. Smoking 20-30 cigarettes a day can cause a clear increase in a person's heart rate. Smoking acts as a vasoconstrictor of small arteries preventing blood flow to regions of the body such as the feet. In the long term, cigarettes contribute to arteriosclerosis. Long-term smoking greatly ...

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A researcher called Ron van Domburg from the Dijkzigt Hospital Rotterdam in the Netherlands studied 1,000 bypass patients. He concluded that patients who quit smoking in the years following the operation had a better chance of survival than patients who persisted to smoke. He noticed that four years after surgery, a smoker and a person who quit had an equal chance of dying as a result of the heart disease. However after 5 years a quitter's chance improved by 3% and after 15 years the chance rose to 15% and for every year after that the chance of life increased by 1%.

This study shows that smoking greatly contributes to the development of coronary heart disease and a smoker is much more likely to die from the disease than a non-smoker is.

Coronary heart disease is the single greatest cause of death in the western world. Its incidence even in developing countries is growing at an alarming rate. This is widely believed to be linked to some secondary habits as mentioned above such as rich fatty diets, smoking and increased cholesterol. The wealth of a person also determines the likelihood of developing coronary disease. Cheaper foods often contain high levels of fat; cheat meat is often less lean and healthier alternatives prove too costly for families who have limited finances. Exercise that burns off excess fat proves too expensive, as swimming, tennis membership to the gym all costs money. Generally smoking is a much more accepted part of life in poorer areas and so risk is higher. For these reasons despite homogenous health care social class affect the chances of developing coronary disease.

Although global trends show the same increase in heart disease the levels differ around the world. In developing countries the economic status means that there is limited food and that which is available is rarely deep-fried or containing high levels of fat. People get more exercise as the labour involves much more physical work that burns off excess fat. So levels of coronary disease will be lower compared to that of more economically developed countries. For example Britain where food is in plentiful supply and often containing high levels of fat (crisps, chocolate, chips). Most of the labour is employed in the tertiary sector that involves much less physical activity, so levels of heart disease in the more developed parts of the world have higher levels of heart disease.

Factors Affecting the Development of Coronary Heart Disease

Twelve million Americans, that's one in every five people, suffer from coronary heart disease (CHD). It is the number one killer of men and women in almost every economically developed country. In the UK alone 1.4 million people suffer from angina and 300 thousand experience heart attacks yearly, these two are the most common and serious symptoms of Coronary Heart Disease. It is clear that this disease, which is ever expanding, has already tightly gripped the world we live in, nobody doubts its danger or the fact that steps must be taken to prevent its occurrence. To do this however the factors that affect its development must be investigated and from this data preventative steps can be suggested.

Coronary heart disease is a chronic disease in which there is a hardening of the arteries on the surface of the heart, this is also known as arteriosclerosis. The arteries become so narrow and stiff that they block the free flow of blood that is so vital to the function of the circulatory system. When this happens cardiac ischemia takes place, there is not a satisfactory amount of highly oxygenated blood reaching the heart. Some feel nothing during this process, which is called silent ischemia, whereas the majority suffer from angina, which, during intensity, can trigger cardiac arrest, where the heart stops beating, or even congestive heart failure occurs. The essences of the problem is the build up of plaque on the walls of the arteries, low-density lipoproteins (LDL's) stick to the walls and are only carried away from the arteries by high-density lipoproteins (HDL's), these two cholesterol variations are key to the whole process. When enough oxygen is not transported to the hearts muscle tissues they will eventually weaken and die, this is when a heart attack is inevitable.

There are many factors that contribute to the development and progression of coronary heart disease, it has identified that a person's family medical history can help determine whether they are vulnerable to it or whether or not they have a variant of the low density lipoprotein receptor gene which causes high LDL levels and coronary heart disease at a young age.

A more obvious method would be to carefully control your food intake so that appropriate substances such as vitamins and minerals could counteract the process, other foods however such as fats and oils such as saturated fat and tropical oils have been known to speed up the diseases development because of their high cholesterol content.

Obesity and being overweight are major risk factors for a number of serious health conditions, including high blood pressure, diabetes, heart attack and stroke, all of which worsen or develop cases of CHD. The best way to limit a person's risk regarding this is to limit the amount of fat available to them in their diet, or exercise.

Exercising is one of the most important factors that affect the development of coronary heart disease, physically, it can slow or even reverse the process of arteriosclerosis, as well as lower blood pressure and reduce cholesterol levels, and this is without doubt beneficial. If blood pressure is lowered, through strengthening of the heart and arteries because of their more intensive use, the risk of CHD should be reduced. The lowering of cholesterol levels would mean the walls of the arteries would be less likely to harden through the build up of plaque, the whole cause of the disease in the first place. Emotionally, it can reduce levels of stress and depression. This may seem irrelevant but quite often stress can lead to high-risk practices such as overeating, smoking, high blood pressure (hypertension) and a lack of exercise, all of which actually prove detrimental in a persons fight against coronary heart disease. In addition, chronic stress may be a direct contributor to poor heart health because it produces increases in blood pressure that could become permanent.

Smoking is a habit that doesn't go well with coronary heart disease. Cigarettes contain a substance called Nicotine, which is known to contract blood vessels and to release hormones that raise blood pressure, a condition that worsens CHD. Also, Smokers have distinctly higher levels of carbon monoxide in their blood, a gas that reduces the amount of haemoglobin available to carry oxygen. This in turn means that the availability of oxygen to the tissues is reduced, this includes muscle tissues in the heart, they are more likely to be weakened and may die which would cause a heart attack. None of the mentioned effects of smoking would appear to be anything else but supportive of the development of coronary heart disease.

Factors affecting the development of coronary heart disease

The heart is a powerful pump responsible for delivering blood to all the vital organs through a complex network of arteries and veins. It is essential that your heart, veins and arteries remain in good condition. Arteries have different names, depending on what part of the body they supply; those supplying the heart itself are called coronary arteries. When these arteries are affected, the result is coronary heart disease.

Coronary heart disease is the most common cause of death in the UK accounting for around 125,000 deaths a year: approximately one in four deaths in men and one in six deaths in women. It is also the most common cause of premature death in the UK: 26% of premature deaths in men and 16% of premature deaths in women.

When a person has coronary artery disease, the vessels that supply blood to the heart are narrowed, limiting the amount of blood and oxygen that reach the heart. The usual cause is a build up of fatty deposits (also called plaques) on the walls of the arteries.

For the heart to beat and pump blood normally, the heart muscle needs a non-stop supply of oxygen from the blood. If severe coronary artery disease is not treated, not enough blood reaches the heart. This may cause damage to the heart muscle (myocardial infarction or "heart attack").

As the coronary arteries narrow, patients will often experience chest pain or tightness, known as angina. This pain may spread to the left shoulder or arm, or to the neck and jaw. The pain can occur at times of exercise, stress or strain, particularly in cold weather.

Heart disease is a leading cause of death and illness that affects millions of people worldwide. Conditions that increase your risk of developing heart disease are called risk factors. The more risk factors you have, the greater your risk is of developing heart disease. However, you can reduce your risk of heart disease by modifying your risk factors.

Coronary heart disease occurs when fatty deposits build up on the inner walls of the coronary arteries. This slow, progressive process is called arteriosclerosis. The deposits are called plaque, and they are made of fat, cholesterol and other substances. A high level of blood cholesterol makes it more likely that arteriosclerosis will develop. Cholesterol occurs naturally in the body and is found in many foods. In Western society, where virtually everyone has some degree of arteriosclerosis, this process of plaque development begins in childhood and continues throughout life.

Factors that increase your risk of coronary heart disease are high blood pressure, cholesterol, smoking, lack of exercise, stress, being overweight and excessive alcohol intake. These are all factors that you can control but there are factors you cannot change such as family history of coronary heart disease, sex and age.

Lowering your cholesterol level is vitally important to prevent continued arteriosclerosis. The CHD national service framework suggests a cholesterol target of less than 5.0mmol/l. About 66% of men in Britain and 67% of women have blood cholesterol levels above this. (British heart foundation web site) To reduce blood cholesterol levels you need to eat foods that are low in fat and cholesterol, being especially careful to reduce saturated and hydrogenated fats. Physical activity and drugs can also reduce it.

Cholesterol is a fat like substance produced by your liver. You also get cholesterol from many of the foods you eat. Although it is needed by your body to function properly, too much cholesterol can clog coronary arteries, making it hard for blood to bring in oxygen and nutrients. If and artery becomes blocked, blood flow stops and a heart attack may occur. There are two types of cholesterol: - low density lipoprotein (LDL) cholesterol - the 'bad' cholesterol - high-density lipoprotein (HDL) cholesterol - the 'good' cholesterol.

High levels of LDL cholesterol increase your chance of heart attack and other heart diseases, such as arteriosclerosis and angina. HDL cholesterol is 'good' because it helps clear LDL cholesterol out of your arteries.

Lowering blood pressure is also an important to reduce the risk of suffering from coronary heart disease. Losing weight is the most effective lifestyle change to lower blood pressure and can help lower blood cholesterol levels.

Smoking contributes to coronary heart disease, reduces oxygen supply in the blood, worsens cholesterol and increases clotting proteins. Stopping will dramatically decrease the risk of a heart attack.

Coronary Heart Disease - A disease of the developing world

Coronary Heart Disease is the most common serious medical condition in the Western world. It affects people more as they grow older and impinges on both men and women, rich and poor, black and white. In the USA 7.5% of white people suffer from heart disease. 6.9% of black people suffer. This small difference in percent is not due to different genetics, but most likely different lifestyles the people lead.

Coronary heart disease is the disease that involves the narrowing and blocking of the coronary arteries. These arteries line the heart and supply it with oxygen-rich blood and nutrients. There are two types of CHD. 'Angina Pectoris' is where a blockage occurs in the arteries preventing blood passing to tissues which is brief and incomplete, no damage occurs if the blockage allows blood through again, but if blood is still unable to pass through and a portion of the muscle is destroyed it is called a 'Myocardial Infarction', this is commonly called a 'heart attack'.

The narrowing and furring of the coronary arteries cause CHD. As the body gets older, the tissues and systems change, artery walls become harder and they thicken, this general process is called 'Arteriosclerosis'. This increases the risk of heart disease because as the walls thicken, the arteries become narrower, increasing the risk of blockage of the flow of blood to the heart muscle. Also, through the individual diets of different people the arteries become furred and blocked by Plaques and fatty deposits such as cholesterol and minerals e.g. calcium, this makes them hard and brittle. This process is called 'Arteriosclerosis'. Sometimes the plaques lining the artery wall cracks and bleeds, this creates blood clots, which cause the arteries to become even narrower.

Over the years, scientists have found that young children have fatty streaks on the wall of the arteries, this is the first sign of furring of the arteries, but what they do not understand is how these fatty streaks develop into atheroma - a sludgy build up of fats and debris - which is laid down in the blood vessel. 'In Africa people have fatty streaks but do not develop atheroma' observes Dr David Newby. This implies that the development of atheroma may be affected by other factors in our modern life e.g. behaviour, pollution, diet and how active we are in our lifestyles.

Possessing a high level of cholesterol is generally thought to be a threatening as, quite rightly, it can lead to a higher risk of developing heart disease. However, there are two types of cholesterol, that both have an affect on the risk of heart disease. There is low-density lipoprotein (LDL) - bad cholesterol and high-density lipoprotein (HDL) - good cholesterol. LDL sticks to the artery wall, raising the risk of heart disease. In contrast HDL cholesterol helps clear away LDL.

When LDL cholesterol is oxidised it can lead to the early development of arteriosclerosis, this happens through the release of free radicals, which damage cells. Whilst the LDL cholesterol is oxidised it stimulates the build up of cells named foam cells. These cells change the fatty streaks into early atheroma.

A layer of cells covering the heart and blood vessels known as the endothelium lubricates the blood vessels, easing blood flow. It is thought that flawed functioning of the endothelium could be the basis of CHD. The faults could be through high cholesterol, a virus or harmful chemicals from cigarettes or pollution.

Another way that the cells of the endothelium may cause an increase in the development of CHD is through a reduction in the production of nitric oxide. It relaxes the blood vessels and keeps them open, preventing clotting and inflammation. If there is a shortage of nitric oxide, blood pressure may rise because the blood vessels contract.

Other hormones are secreted by the endothelium, a hormone called endothelin narrows the blood vessels, which helps to regulate blood pressure. Drugs that have been made to counter-act endothelin have worked very successfully on animal tests, and there is a significant reduction in the risk of dying of a heart attack.

There are many complicated reasons as to why people develop CHD. It is known as a multi-factorial disease; this means that there is commonly more than one factor involved in its development.

It has been found that women's risk of developing CHD after their menopause increases significantly. This is because the hormone oestrogen acts to protect the arteries; it is thought that oestrogen acts as an anti-oxidant, which clears up the free radicals, which are involved in the development of arteriosclerosis. There is another group of hormones that protects pre-menopausal women known as prostaglandins. The uterus secretes these. Prostaglandins control blood clotting and the smooth muscle activity of the blood vessels. Both factors obviously are closely linked to CHD.

There are a number of uncontrollable risks that contribute to the development of CHD.

One reason for an increased incidence of CHD in developed countries is that we are all living longer. Arteriosclerosis and CHD take a long time to develop, and as time goes by and, the body becomes older, it becomes less able to repair damage caused by other factors.

Gender also affects the development of CHD in many ways. As talked about above, before passing the menopause, women have a variety of hormones that protect the arteries. So men between the ages of 35 and 44 are 6 times more likely to sustain a heart attack than women. Women after the age of 65 are just as likely to suffer from heart disease as men.

An increased risk of suffering heart disease may run in the family. There are conditions such as inherited Familial Hyperlipidaemia. Sufferers have naturally raised levels of cholesterol, and are thus at higher risk of developing CHD. The gene responsible for this has been found and now there is a blood test to check your cholesterol and see if FH runs in the family. Arteriosclerosis and heart disease appear to run in some families as well. This may be because there could be genetic differences in the way our bodies handle fat. The incidence of naturally high blood pressure is also being researched with the intention of finding the gene responsible.

It appears that if a family from South Asia comes to the UK, they may be at a much higher risk of developing CHD than there relatives that remained in South Asia. This is particularly true of the female members of such an immigrant family. This indicates that environmental factors such as lifestyle, diet and exercise have serious effects on risks of developing CHD.

There are a number of controllable factors that affect the risk of developing CHD.

Smoking is a deadly habit that is very addictive; it is most commonly associated with lung cancer but also affects the heart. Smoking increases the risk of developing CHD by 5 times. Cigarette smoke also reduces the amount of HDL (good cholesterol) and in women it lowers the level of oestrogen in the body. As explained before, natural levels of hormones such as oestrogen are known to protect the arteries.

Hyperlipidaemia (raised levels of blood fat) obviously affects the blood flow and can lead to arteriosclerosis. A diet that is low in saturated animal fats and high in fruit and vegetables reduces the build up atheroma.

Physical inactivity is recognized as a risk factor for CHD, many people do not feel it important to exercise and do not have the time for it. Regular activity reduces the levels of LDL cholesterol and increases the levels of HDL cholesterol. Physical activity increases the body's metabolism, which encourages the body to use fat for energy and burn fat more efficiently. Exercise lowers resting blood pressure and also reduces the stickiness platelets, this is very important, as blood clots are the main trigger for heart attacks. Activity helps to control appetite, which reduces the habit of unhealthy snacking. It also can help ease depression; during exercise the body releases chemicals called endorphins, which enhances feelings of good health and may ease stress.

Alcohol has been assumed for a long time to be bad for your health, so it was thought to be a risk factor. However, new research from Mediterranean countries has found that drinking small amounts of wine regularly may be linked to their relatively low figures for the incidence of CHD. It has now been recognised by many, that small amounts of wine may be good for you. It has yet to be discovered at what volume it is bad for you.

Stress has also been linked to raised levels of CHD. Stress might result from a number of possible factors, such as a particularly demanding job, a lack of money or not having a supporting network of family and friends. Mentally, stress can cause a lack of confidence, which in turn may raise blood pressure, which in turn is known to increase the risk of CHD.

References: 'www.bio-zone.co.uk' - web site

'www.bio-links.co.uk' - web site

- web site

'www.dphpc.ox.ac.uk' - web site

Risk Factors and Coronary Heart Disease - AHA Scientific Position

Extensive clinical and statistical studies have identified several factors that increase the risk of coronary heart disease and heart attack. Major risk factors are those that research has shown significantly increase the risk of heart and blood vessel (cardiovascular) disease. Other factors are associated with increased risk of cardiovascular disease, but their significance and prevalence haven't yet been precisely determined. They're called contributing risk factors.

What are the major risk factors that can't be changed?

Increasing age – About four out of five people who die of coronary heart disease are 65 or older. At older ages, women who have heart attacks are more likely than men are to die from them within a few weeks.

Male sex (gender) – Men have a greater risk of heart attack than women do, and they have attacks earlier in life. Even after menopause, when women's death rate from heart disease increases, it's not as great as men's until both groups reach the 80s.

Heredity (including Race) – Children of parents with heart disease are more likely to develop it themselves. African Americans have more severe high blood pressure than Caucasians and a higher risk of heart disease. Heart disease risk is also higher among Mexican Americans, American Indians, native Hawaiians and some Asian Americans. This is partly due to higher rates of obesity and diabetes. Most people with a strong family history of heart disease have one or more other risk factors. Just as you can't control your age, sex and race, you can't control your family history. Therefore, it's even more important to treat and control any other risk factors you have.

What are the major risk factors you can modify treat or control by changing your lifestyle or taking medicine?

Tobacco smoke – Smokers' risk of heart attack is more than twice that of non-smokers. Cigarette smoking is the biggest risk factor for sudden cardiac death. Smokers have two to four times the risk of non-smokers. Smokers who have a heart attack also are more likely to die and die suddenly (within an hour). Cigarette smoking also acts with other risk factors to greatly increase the risk for coronary heart disease. People who smoke cigars or pipes seem to have a higher risk of death from coronary heart disease (and possibly stroke) but their risk isn't as great as cigarette smokers'. Exposure to other people's smoke increases the risk of heart disease even for non-smokers.

High blood cholesterol – As blood cholesterol rises, so does risk of coronary heart disease. When other risk factors (such as high blood pressure and tobacco smoke) are present, this risk increases even more. A person's cholesterol level is also affected by age, sex, heredity and diet.

High blood pressure – High blood pressure increases the heart's workload, causing the heart to thicken and become stiffer. It also increases your risk of stroke, heart attack, kidney failure and congestive heart failure. When high blood pressure exists with obesity, smoking, high blood cholesterol levels or diabetes, the risk of heart attack or stroke increases several times.

Physical inactivity – An inactive lifestyle is a risk factor for coronary heart disease. Regular, moderate-to-vigorous physical activity helps prevent heart and blood vessel disease. The more vigorous the activity, the greater your benefits. However, even moderate-intensity activities help if done regularly and long term. Exercise can help control blood cholesterol, diabetes and obesity, as well as help lower blood pressure in some people.

Obesity and overweight – People who have excess body fat — especially if a lot of it is at the waist — are more likely to develop heart disease and stroke even if they have no other risk factors. Excess weight increases the heart's work. It also raises blood pressure and blood cholesterol and triglyceride (tri-GLIS'er-id) levels, and lowers HDL ("good") cholesterol levels. It can also make diabetes more likely to develop. Many obese and overweight people may have difficulty losing weight. But by losing even as few as 10 to 20 pounds, you can lower your heart disease risk.

What other factors contribute to heart disease risk?

Individual response to stress may be a contributing factor. Some scientists have noted a relationship between coronary heart disease risk and stress in a person's life, their health behaviours and socio-economic status. These factors may affect established risk factors. For example, people under stress may overeat, start smoking or smoke more than they otherwise would.

Drinking too much alcohol can raise blood pressure, cause heart failure and lead to stroke. It can contribute to high triglycerides, cancer and other diseases, and produce irregular heartbeats. It contributes to obesity, alcoholism, suicide and accidents.
Heart disease describes a variety of disorders and conditions that can affect the heart. The most common type of heart disease is coronary heart disease (CHD), also called coronary artery disease.

The word 'coronary' means crown, and it is the name given to the arteries that circle the heart like a crown. The coronary arteries supply the heart muscle with oxygen and nutrients.

Coronary heart disease develops when one or more of the coronary arteries that supply the blood to the heart become narrower than they used to be. This happens because of a build-up of cholesterol and other substances in the wall of the blood vessel, affecting the blood flow to the heart muscle.

Deposits of cholesterol and other fat-like substances can build up in the inner lining of these blood vessels and become coated with scar tissue, forming a bump in the blood vessel wall known as plaque.

Plaque build-up narrows and hardens the blood vessel, a process called arteriosclerosis, or hardening of the arteries.

Eventually these plaque deposits can build up to significantly reduce or block blood flow to the heart.

Many people experience chest pain or discomfort from inadequate blood flow to the heart, especially during exercise when the heart needs more oxygen. Without an adequate blood supply, heart muscle tissue can be damaged.

Although we typically think of arteriosclerosis as a disease of old age, the process begins as early as childhood, making prevention of coronary heart disease a priority for everyone.

It's not easy to tell if you have coronary heart disease, since the disease rarely causes symptoms in its early stages. That is why it's important to see your physician regularly and evaluate your diet and lifestyle habits. Your physician can detect early warning signs of CHD, such as high blood pressure or high cholesterol levels.

What happens, as coronary heart disease gets worse?

As coronary heart disease develops, more damage to the heart occurs and the following conditions may develop:

Angina

As CHD progresses, build-up of cholesterol and other fat-like materials significantly reduces blood flow to the heart. If the heart is not getting enough oxygen, a person may experience pain or discomfort in the chest known as angina, especially during exercise or increased activity.

Symptoms of angina include:

A feeling of discomfort or pressure felt in the chest, ranging from a vague ache to a crushing sensation
Pain or pressure in the left arm, shoulder, or throat
Difficulty catching your breath

CHD is the most common cause of angina. Angina is a sign that the heart muscle is not receiving enough oxygen and nutrients.

Heart Attack

If blood flow to any part of the heart is completely blocked, the cells in that part of the heart begin to die, causing a heart attack. Heart attacks usually happen when a previously narrowed coronary artery is suddenly blocked or otherwise closed off.

Symptoms of a heart attack vary widely for each person but can include:

Pain or pressure in the chest, shoulders or arms (most commonly on the left side), neck, or lower jaw.

Shortness of breath

Weakness

Rapid heart beat

Light-headedness or faintness

Profuse sweating

Nausea or vomiting

Facts About Heart Disease

More than 12 million Americans suffer from CHD. It is the No. 1 killer of adult Americans, both men and women.

The death rate from coronary heart disease (CHD) has fallen by 40 percent over the past 20 years. This drop is partly because more people are eating right and exercising regularly, and partly because of advances in medical care for those who do have heart disease.

One in ten women aged 45 to 64 has some form of heart disease. The rate increases to one in five for women 65 years of age and older.

Close to one-half of Americans with high blood pressure- an important risk factor for heart disease - don't even know they have it.

Heart disease is the leading cause of death in cigarette smokers.

Based on new weight-for-height guidelines, more than one-half of Americans are considered overweight or obese. Middle-aged men who are obese are three times more likely to have a heart attack than men of normal weight.

Deposits of cholesterol and other lipids, or fat-like substances, can begin to form on the artery wall as early as childhood. In studies of 22-year-old men killed during the Korean War, one-third had significant deposits in their arteries.
Only about one-quarter of American adults meet current recommendations for physical activity, which is a good way to help prevent heart disease.

How Can You Reduce Your Risk For Heart Disease? -

In order to reduce your risk of coronary heart disease (CHD), you first must identify what may be putting you at risk. Determine if you're at risk by reviewing your lifestyle and diet. Ask your physician to check your blood cholesterol level. If you have only one uncontrollable risk factor, smoking or being overweight could make it worse.

Even if you are at risk for coronary heart disease, you can eliminate many of the major risk factors for CHD by making simple changes in diet and lifestyle. These changes are healthy for the entire family and reduce your risk of other diseases as well. They include:

Control your cholesterol level
Control high blood pressure (hypertension)
Stop smoking
Lose weight if you need to
Get active
Manage stress

Q: Does a diet high in sugar increase the risk for coronary heart disease?

A: There is no evidence that high sugar intake by itself causes coronary heart disease. However, foods high in sugar-such as cakes, cookies and ice cream-are also often high in fat, which does increase risk for heart disease. Further, foods high in sugar displace other more nutritious foods, such as fresh fruits and vegetables, from your diet.

Q: Does alcohol decrease the risk of coronary heart disease?

A: A glass or two of wine has been shown to increase HDL cholesterol levels (the good kind of cholesterol that helps clean out blood vessels). But more than two drinks a day can be harmful, raising blood pressure and throwing off cholesterol balance. Alcohol is also a fairly concentrated source of calories and can contribute to weight gain, which increases risk for CHD.

Q: Once cholesterol-rich deposits form in my arteries, do they ever go away?

A: The artery-clogging deposits of cholesterol and other fat-like substances that cause heart disease can begin as early as childhood and continue to form, as we grow older. New research, however, has shown that a very low-fat diet combined with regular exercise and other healthy lifestyle changes can actually help shrink and clear out these deposits in the blood vessels, reversing CHD.

Heart-healthy changes in diet and lifestyle can significantly reduce your risk for coronary heart disease (CHD), and it is never too late to make these changes.

Major risk factors for coronary heart disease include high blood cholesterol levels, high blood pressure, cigarette smoking, inactivity, and diabetes. Being overweight or under stress can aggravate these risk factors.

Eating a diet that is low in fat (especially the saturated fat found in most animal foods) and cholesterol and rich in fruits, vegetables, and whole grains will help lower your cholesterol level.

Losing weight if needed, exercising regularly, and lowering your sodium (or salt) intake will significantly lower your blood pressure.

If you need to stop smoking, make a firm commitment to yourself and plan activities to keep your hands and mouth busy. When you stop smoking, your risk for coronary heart disease begins to fall immediately.

Exercise more by gradually increasing the minutes you spend being physically active. You should strive to accumulate at least 30 minutes of physical activity on most or all days of the week.

If you need to lose weight, cut back on your calorie intake modestly while increasing physical activity. Being active is one of the most important things you can do to lose weight.

What Is Coronary Artery Disease?
Coronary artery disease (CAD) occurs when the arteries that supply blood to the heart muscle (coronary arteries) become hardened and narrowed. The arteries harden and become narrow due to the build-up of plaque on the inner walls or lining of the arteries (arteriosclerosis). Blood flow to the heart is reduced as plaque narrows the coronary arteries. This decreases the oxygen supply to the heart muscle.

CAD is the most common type of heart disease. It is the leading cause of death in the U.S. in both men and women.

When blood flow and oxygen supply to the heart are reduced or cut off, you can develop:

Angina is chest pain or discomfort that occurs when your heart is not getting enough blood.

A heart attack happens when a blood clot suddenly cuts off most or all blood supply to part of the heart. Cells in the heart muscle that do not receive enough oxygen-carrying blood begin to die. This can cause permanent damage to the heart muscle.

Over time, CAD can weaken your heart muscle and contribute to:

Coronary artery disease is also called:

CAD

Coronary heart disease (CHD)

Heart disease

Ischemic heart disease.

What Causes Coronary Artery Disease?
CAD is caused by arteriosclerosis, the thickening and hardening of the inside walls of arteries. Some hardening of the arteries occurs normally as you grow older.

In arteriosclerosis, plaque deposits build up in the arteries. Plaque is made up of fat, cholesterol, calcium, and other substances from the blood. Plaque build-up in the arteries often begins in childhood. Over time, plaque build-up in the coronary arteries can:

Narrow the arteries so that less blood can flow to the heart muscle

Completely block the arteries and the flow of blood

Cause blood clots to form and block the arteries.

Plaque in the arteries can be:

Hard and stable. Hard plaque causes the artery walls to thicken and harden. This condition is associated more with angina than with a heart attack, but heart attacks frequently occur with hard plaque.
Soft and unstable. Soft plaque is more likely to break open or apart and cause blood clots. This can lead to a heart attack.

What Makes Coronary Artery Disease More Likely?
About 13 million people in the U.S. have CAD. It is the number one killer of both men and women. Each year, more than half a million Americans die from CAD.

There are factors that make it more likely that you will develop CAD. These are called risk factors.

How is Coronary Artery Disease Treated?
The treatments for CAD include lifestyle changes, medications, and special procedures. The goals of treatment are to: