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Updated 31 July 2014

Atherosclerosis

Atherosclerosis is a condition in which arteries become hardened and narrowed due to the deposition of cholesterol-rich plaques in the artery wall.

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Summary

  • Atherosclerosis is a condition in which arteries become hardened and may become narrowed due to the deposition of cholesterol-rich plaques which may initiate clot formation that can obstruct the flow of blood. This is associated with high blood cholesterol levels and other conditions such as hypertension and diabetes.
  • The effects of the condition will be determined by the organ most affected, e.g. the heart, brain or limbs, giving rise to conditions such as heart attack, stroke or claudication respectively.
  • Diagnosis is simple and treatment may include lifestyle changes, medication and even surgery such as heart bypass grafting.
  • Cure and total prevention is not realistically possible, but a prudent lifestyle and appropriate medication can significantly delay the onset of problems.
  • Those with a family history of high cholesterol or any of the associated risk factors should regularly be screened by means of a full fasting lipogram.

Definition

Atherosclerosis, also known as arteriosclerosis or "hardening of the arteries", is a disease process in which cholesterol and other fat from the circulation collect in the arterial wall together with cells and some scar tissue may also form. While it is unlikely that the cholesterol-rich lesion will protrude into the inside of the artery to obstruct blood flow, its rupture may lead to clotting, the extent of which vary from minor amounts that do not impair flow significantly, to complete obstruction. Calcification may also occur in such lesions.

It occurs to some extent in most people as they get older, but more rapidly in some for reasons which are largely preventable.

Causes

Arterial walls develope "plaques" over a long period of decades. These begin as thin, fatty streaks in the inner portion of an arterial wall. In a healthy, young person the streaks may come and go.

But if arteries are stresssed or damaged – from high blood pressure or smoking or excess cholesterol and related fatty substances, for example – the inner lining of the wall attract cells and more cholesterol. This sets in motion the series of events described below which create a fully-fledged atherosclerotic plaque.

Over time, various substances such as fats, cholesterol, platelets (particles that cause blood clotting) and cellular debris are deposited at these sites. Eventually, scar tissue and sometimes calcium crystals surround the fatty plaque, making the arteries hard and inelastic.

As a plaque grows, it produces a rough area in the artery's normally smooth inner surface. This rough area can trigger the formation of a thrombus (clot), decreasing and eventually blocking blood flow in the artery. Large amounts of excess fat also accumulate in the wall which is liable to rupture into the lumen of the artery.

Atherosclerosis itself also predisposes towards the formation of a blood clot or thrombus that is often the precipitating cause of the acute event. Portions of the plaque may break off to deposit emboli in arteries supplying the brain particularly, and elsewhere in the body.

Through any of these processes the affected tissue is then starved of blood and oxygen with the result that the cells may die or become severely damaged.

Development of a plaque also deforms the arterial wall, increasing turbulence and resistance to blood flow. As resistance to flow increases, or turbulence the damage may be enhanced. High blood pressure not only increases the stress on the artery but also induces the heart to work harder to pump blood, causing it to enlarge and ultimately heart failure. High blood pressure also has deleterious effects on cerebral arteries and the small arteries to the eyes and kidneys, resulting in failure of these organs.

Outcome

Because atherosclerosis usually progresses slowly over many years, it is commonly thought of as an affliction of the elderly.

However, studies show that arterial deposits can begin in childhood, with significant plaque formation by the time a person is 30. In some people it progresses rapidly in their third decade; in others it doesn’t become threatening until they’re in their fifties or sixties. Women, in particular, are generally but not invariably protected before menopause.

Atherosclerosis may never seriously affect the overall health of some people who have it. In many others, however, it is an important cause of illness and early death.

Untreated, it can lead to the conditions listed under "Symptoms and Signs". In most cases, improvements in lifestyle (see "Treatment" and "Prevention") and appropriate medical treatment, can retard or even reverse the progress of the disease.

Physical effects

Atherosclerosis is the most common cause of coronary artery disease in adults. The changes that result from atherosclerosis can be divided into reversible and irreversible:

  • The reversible changes generally occur in the first three decades of life. These do not result in clinical disease and can disappear with appropriate treatment, leaving behind an entirely normal artery. The reversible changes result in some swelling of the wall of the artery due mainly to some accumulation of lipids inside the cells which have gathered in the wall of the artery itself.
  • The irreversible changes are called atherosclerotic plaque – or just "plaque". These occur later in life, except in unusually severe cases in which they may appear earlier. They can go on to cause chronic (ongoing) or acute (sudden) symptoms or a combination of the two. Plaque can be modified by vigorous treatment and the risks associated with it can be significantly reduced. But once formed, plaque never regresses completely.

After plaque has formed it can cause problems in a number of different ways. If an established plaque ruptures, the resulting events can cause a heart attack or stroke.

Plaque ruptures if the tissue covering it erodes sufficiently to allow blood to come into contact with the lipid core. This causes the blood to clot (thrombose). If the clot is in one of the coronary arteries it can cause symptoms such as chest pain or it can cause a fatal heart attack. It can also lodge in the brain and cause a stroke.

Plaque can also become thickened with calcium deposits, or the lipid core can crystallise. A fibrous cap can form, protecting the plaque from rupturing as easily, but further stiffens the artery – so-called hardening of the arteries.

Associated risk factors

Atherosclerosis is the major cause of death and disability in developed nations through the clinical mechanisms described above. Coronary artery disease and its complications, together with stroke, are responsible for more deaths than all other causes combined.

There is also an emerging epidemic of heart attacks in Africa and other developing countries as more people adopt the sedentary western lifestyle including a high-fat, high-cholesterol diet, little exercise and becoming obese. Heart disease is one of the leading causes of premature death in South Africa, notably in the white and Indian communities but increasingly in the black population as well.

Most people will develop some arterial deposits over time, but certain factors significantly encourage this process. These are called risk factors:

  • Age. The risk of developing atherosclerosis increases after age 35, although it can begin much earlier. Blood vessels lose a certain amount of elasticity with ageing.
  • Gender. Premenopausal women are much less likely than men of the same age to have atherosclerosis. But after menopause, women's risk increases to equal – or even exceeds – that of men.
  • Heredity. A family history of atherosclerosis or other circulatory diseases may denote increased risk in closely related family members. This is particularly relevant in South Africa, where there is a high incidence of familial hypercholesterolaemia in several communities.
  • Obesity. Obese people are more likely to have atherosclerosis because they are predisposed to high triglyceride, low HDL-cholesterol and raised total cholesterol levels, as well as high blood pressure, thrombus formation and diabetes mellitus.
  • Physical inactivity.
  • Diabetes mellitus.
  • High level of blood cholesterol (hypercholesterolaemia): especially the cholesterol carried in LDL or low-density lipoproteins from the liver to the tissues.
  • Low levels of high-density lipoprotein (HDL), which transport cholesterol from cells to the liver, are also associated with a high risk of heart disease. This is often associated with raised concentrations of triglyceride (also a fatty substance similar to cholesterol).
  • Hypertension (high blood pressure).
  • Smoking. A smoker's risk of coronary artery disease is directly related to the number of cigarettes smoked daily. In people who already have a high risk of heart disease, smoking is particularly dangerous. Smoking:
    • decreases the level of "good" HDL cholesterol and may enhance the toxic effect of "bad" LDL cholesterol.
    • raises the blood carbon monoxide level, which may increase the risk of injury to the lining of arterial walls.
    • constricts arteries already narrowed by atherosclerosis, further decreasing blood flow to the tissues.
    • increases the blood's clotting tendency, thus increasing the risk of peripheral arterial disease, coronary artery disease, stroke and obstruction of an arterial graft after surgery.

Symptoms and signs

Atherosclerosis usually produces no symptomsfor a long time but may suddenly or slowly reduce the blood supply to an organ. This may be partial or complete, acute or chronic. Complete obstruction is generally the result of a thrombus or an embolus. The symptoms and outcome (prognosis) will vary accordingly.

The first symptom of in adequate blood supply is generally pain, and may only happen during exercise (of the heart or legs at which times the blood flow can't keep up with the tissue’s demand for oxygen.

For instance, during exercise, you may feel chest pain (angina) because of lack of oxygen to the heart; or leg cramps because of lack of oxygen to the leg muscles (claudication). These symptoms may set in suddenly when a clot forms; and could improve when the clot is digested by normal processes or could progress if this does not happen. This may be the presenting event without previous warning symptoms.

Symptoms may vary from quite characteristic to atypical .depending on the several incidental factors.

It is important to note that persons with diabetes often do not experience pain as an early warning sign. They may thus have advanced disease, e.g. coronary artery disease, without being aware of it – until it reaches a critical phase and causes a heart attack.

Women, also, generally do not have the same "classical" symptoms and signs listed below. In these two categories of patient – women and diabetics – there must be a greater awareness and index of suspicion than in others. These patients should thus be tested sooner and more frequently.

The more characteristic clinical presentations are described below which depend on the organ mainly affected and the severity of the obstruction:

Heart
The complications resulting from atherosclerosis can arise slowly over time as blood flow is reduced or may be of sudden onset .

The common ways in which the heart is affected are through:

  • Stable or exercise-induced angina
  • Unstable or crescendo angina
  • Heart attack (acute myocardial infarction)

Coronary artery disease (coronary heart disease): occurs when atherosclerosis results in narrowing of the coronary arteries (arteries supplying blood to the heart muscle). As the coronary arteries narrow, angina (chest pain) may result – especially on exertion.

In a heart attack, a portion of the heart muscle actually dies; the technical term is "myocardial infarction". If this occurs very suddenly and rapidly it is called an acute myocardial infarction.

Symptoms may include:

  • a pressing, centrally located chest pain (angina), which may also be felt in the arms and hands as tingling or numbness
  • shortness of breath

Less characteristic features include:

  • sweating
  • nausea
  • dizziness or light-headedness
  • palpitations
  • pain in the jaw or shoulder/upper arm

Brain
Stroke:
A thrombus may form in an artery to the brain that has been affected by atherosclerosis, or a piece of atherosclerotic plaque in an artery supplying the brain can break off to form an embolus dislodged piece that travels and downstream causes a blockage , or the weakened arterial wall may rupture and bleed. The end result in all cases is greater or lesser damage to the brain, which presents as a stroke.

Warning signs may include:

  • atherosclerosis of cerebral arteries does not present with pain, but may cause progressively diminished mental functioning, and episodes of light-headedness.
  • It may also present with very minor strokes, called transient ischaemic attacks, accompanied by temporary dizziness or confusion, incoordination, numbness and loss of speech. These features are relieved within 24 hours.

An acute, more severe obstruction or bleed may present with:

  • Headache – often severe and sudden
  • Unconsciousness and collapse
  • Weakness or paralysis on one side of the body
  • Sudden, severe numbness in any part of the body
  • Speech and visual disturbances or severe muscle incoordination.
  • The presentation may be progressive over a short period of time or may be sudden and overwhelming. In the case of a stroke, the neurological abnormalities are persistent, often taking months to improve. Full restoration of normal function is rare. Strokes can result in a bizarre variety of neurological problems, sometimes very localised and specific.

Legs
Peripheral arterial disease:
Atherosclerosis can impair the flow of blood in the major arteries to the legs. The resultant reduced blood flow may cause crampy leg pain during exercise, which is called "intermittent claudication".

If blood flow is severely restricted, parts of the leg may become pale on exertion or "blue" (cyanotic), feel cool and develop skin sores and ulcers or even gangrene (tissue death). A bruit (specific type of noise) may be heard with a stethoscope over a partly blocked artery. If the artery is totally blocked, there may be no pulse at all.

Abdomen
Abdominal angina and bowel infarction:
When atherosclerosis narrows arteries that supply blood to the intestines, this causes abdominal pain called abdominal angina. Blockage of intestinal blood supply causes a bowel infarction. This is similar to a myocardial infarction, but involves the intestines instead of the heart.

Symptoms include:

  • Dull or cramping pain in the middle of the abdomen, usually beginning 15 to 30 minutes after eating.
  • Severe abdominal pain, vomiting, diarrhoea or constipation caused by complete blockage of an artery in the intestine.

Other conditions
Atherosclerosis may contribute to the development of an aortic aneurysm (a weakening and "ballooning" of the aorta, the main artery leading from the heart) or in renal artery stenosis (narrowing of the kidney arteries).

An aneurysm may rupture, causing a massive haemorrhage or bleed. Narrowing of renal arteries can reduce kidney function and cause high blood pressure.

Diagnosis

Since atherosclerosis is a pathological or disease processin an artery and may no cause any complaints . The doctor needs to establish whether a patient is at increased risk or whether he/she has already developed the clinical complications associated with it.

The risk or predisposing factors have already been discussed. Part of a general medical examination is to enquire into important lifestyle factors such as:

  • dietary habits
  • levels of physical activity
  • smoking habits
  • the amount and kind of alcohol consumed
  • less frequently, levels of emotional stress during daily living

It is also important to determine whether the patient suffers from the important predisposing condition of diabetes mellitus or has already developed symptoms suggestive of early arterial obstruction without even noticing them, for example erectile dysfunction in men. In women, menstrual status is significant since risk increases substantially in post-menopausal women. Hypertension is usually symptom-free until a significant clinical complication results. The doctor also needs to know what medication the patient is currently taking.

After the history has been taken, a physical examination will also help determine risk or the presence or absence of atherosclerosis:

  • Since obesity is an important risk factor, the doctor should determine your weight and height. The circumference of your waist and hip may also be measured. From this, he can calculate important indices, such as body mass index or waist:hip ratio which provide additional useful information.
  • Hypertension is another significant contributory factor, so blood pressure will be measured.
  • Your heart will be assessed for size and normality of rhythm and the retina of your eyes examined for changes indicating arterial damage due to hypertension or diabetes mellitus.
  • Your pulse should be felt in your neck, groin and legs in order to determine whether the arteries supplying these regions function normally. The doctor may also use his stethoscope to listen for the noise (bruit) made by blood passing over an atherosclerotic plaque. Skin colour, appearance and temperature also convey important information regarding blood supply.

Once the history and clinical examinations are done, the single most important next step is a blood test to measure the amount and type of cholesterol in the blood.

Blood may be withdrawn after an overnight fast for what is often called a lipoprotein profile. This must include total cholesterol, LDL-cholesterol, triglyceride and HDL-cholesterol and glucose determinations. This is an important aspect, because measuring only the total cholesterol level can be misleading: even if the value of the total falls in the normal range, if that total is composed of all "bad" cholesterol, you are at great risk. Other less common assays may also be carried out.

Urine should be examined for sugar and protein. If positive, or if other suggestive evidence is present, a glucose tolerance test and other assays may be performed to ascertain whether diabetes mellitus or some other predisposing condition is present.

In women especially, reduced thyroid function, or hypothyroidism, is not uncommonly a cause of high cholesterol levels. Tests may also be done to determine menopausal status.

There is also a host of other rarer disorders which may occasionally require specific investigation.

Of course, if the patient comes in the first place with obvious symptoms and features of one of the clinical complications of atherosclerosis already described, the doctor will then need to determine the extent and severity of the underlying process in order to recommend appropriate treatment.

There is no simple correlation between the severity of clinical symptoms and the extent and severity of atherosclerosis. In such cases, other complications such as thrombosis or even vascular spasm or embolism may have contributed to the presentation.

The extent of functional atherosclerosis is indirectly but usefully assessed by electrocardiography, at rest or during and after exercise. In addition, more direct assessment is increasingly possible through a series of sophisticated and expensive imaging techniques. These may involve catherisation and injection of a dye so as to visualise the coronary arteries or non-invasive techniques of various kinds which include ultrasound and X-rays amongst others.

Treatment

The treatment will depend on the problems experienced by the patient. If he/she has no symptoms, but is found to have a raised blood cholesterol, then steps will be taken to correct this.

If the cholesterol level is not too high, lifestyle changes (correct diet, sufficient exercise, smoking cessation) may be enough to manage the condition. However, this MUST be checked by follow-up blood tests. The patient must also be made aware that the improvement will only remain while the lifestyle changes remain, and that as soon as old habits are resumed, the cholesterol levels will return to what they were before.

If blood levels are too high, then medication of various sorts may be used. These work in different ways to help the body get rid of excess stored cholesterol, prevent the recycling of existing cholesterol (thereby gradually reducing the total cholesterol present in the body) and by reducing the amount of cholesterol manufactured.

If incomplete blockage of arteries result in problematic angina pectoris or placing the heart at risk of severe damage ( e.g. left mainstem coronary disease) the diseased arteries may be bypassed surgically and a "detour" inserted to carry adequate blood to the organ or the arteries may be opened with a stent. Blockages in the arteries to the brain (carotid arteries) may be also be opened by bypass surgery or a stent in order to prevent strokes.

Medication vs surgery
This decision is best made by a cardiologist and is based on clinical and investigational findings.
If your symptoms are relatively mild ,they may improve with lifestyle changes which definitely have a significant impact in the long term. The drugs for angina pectoris are designed to either reduce your heart’s demand for oxygen, or to allow your blood vessels to relax and widen .so that more blood can be supplied.

If you smoke, you must stop immediately. You should also look carefully at your diet – preferably with the help of a dietician – and cut down on fats, lose weight and do supervised exercise.

But some people are not helped by these relatively simple measures. The next step is to perform coronary angiography to assess the arteries and to decide about angioplasty (catheterisation to relieve the obstructed region and possibly to place a stent to sustain patency) or surgery to bypass a diseased region with one of the less needed arteries in the chest, forearm or a vein from the leg.

Angioplasty means blood-vessel repair. For many people this offers a safe and relatively easy way to deal with blocked arteries.

Coronary angioplasty is done under local anaesthesia and is generally no more than mildly uncomfortable. The different procedures take between 30 minutes to two hours and often only require one day in hospital.

The procedure is called percutaneous transluminal coronary angioplasty (PTCA). This means a procedure which goes through the skin, inside a coronary blood vessel, to repair that blood vessel.

A hollow tube called a catheter is inserted into an artery in the groin. The area will have been numbed first with local anaesthetic. The cardiologist is able to watch the position of the catheter using X-ray images on a television screen. The catheter is guided through your arteries until it arrives at the blocked artery in your heart.

A thinner catheter is then inserted through the first catheter. This has a miniature, deflated balloon at its tip. This is carefully threaded through the blockage. Once in position, the balloon is inflated. This widens the artery and improves the flow of blood through the area. The balloon is then deflated and removed.

Stents after PTCA

In around 80% of patients, a stent is also used after PTCA. This improves the outcome of the whole procedure, making sure that the formerly blocked artery remains open. Before stents were developed there was a chance that the blocked artery would narrow again – called restenosis.

A stent is a mechanical device which is used to keep a hollow tube open.

A coronary stent is a device which can be used in the arteries of the heart when one or more have been narrowed by a build up of plaque. A stent can be inserted after the narrowed area has been opened up using PTCA. The stent is then inserted to prevent the artery from narrowing again.

A coronary stent looks like a coiled spring. It is inserted into the artery using a catheter.

A stent is intended to remain in place permanently to keep the artery open. It is inserted under high pressure and over time actually becomes incorporated into the wall of the artery, so there is no danger of it moving later.

Bare metal stents may, however, also become obstructed with clot or growing cells. This is why drugs such as clopidogrel are prescribed for a long period after placing of a stent or a drug-eluting stent is used to suppress this process. But there are risks involved in the use of drug-eluting stents: the potent anticlotting medication prescirbed to the patient after insertion of an drug-eluting stent may lead to uncontrolled bleeding, particularly if the patient is involved in a road accident or suffers severe physical trauma. Take special care to get the patient to an emergency unit as soon as possible.. 

What about bypass surgery?

It used to be the case that the only option available to surgically deal with blocked coronary arteries was coronary artery bypass surgery. However, these newer techniques have replaced this in around half the people with blocked coronary arteries.

A bypass is a major operation. An artery from your chest wall or a vein from your leg, is attached (grafted) to the blocked part of your coronary artery. This then redirects the flow of blood around the blockage, allowing your heart muscle to receive enough blood and so oxygen.

The cost is generally higher than angioplasty, and it requires a fairly long stay in hospital.

However, for some people with blockage of many of the arteries of their heart, it remains the only option.

What are the advantages of angioplasty?

For many people, coronary angioplasty is as effective as bypass surgery in reducing chest pain and improving your ability to live a normal life. However, it has not yet been proved that either angioplasty or for that matter, bypass surgery, actually prolong life except in some specific circumstances. In spite of this, the technique is so much more effective than drugs in relieving symptoms, that it is preferred in many cases.

Angioplasty offers around a 98% immediate success rate.

Recovery from the procedure is quick, relatively pain free and much less expensive than bypass surgery.

What are the disadvantages of angioplasty?

In around 10 to 15% of people, the artery opened with PTCA renarrows within six months. It is more likely to narrow again if the blockage was very long or was in a very small artery. The good news is that angioplasty can be repeated, but in some patients bypass surgery will be recommended if this occurs. Some cardiologists tend to add one stents after till the patient’s medical aid will no longer pay for any more stents. Some patients end up with 13 stents. This is medically unacceptable. 

The chances of suffering a heart attack or needing an emergency bypass during coronary angioplasty are less than 2%. The risk of dying during the procedure is much less than one percent.

New research shows that the initial higher success rate of angioplasty evaporates after about two years - after two years the survival rates are no better than with bypass surgery.

 Is angioplasty for you?

When you have chest pain and problems with daily life which are not being adequately treated with medication, you will normally be sent to see a cardiologist. He or she will then assess the different treatment options open to you.

You will have a coronary angiogram, which is a technique in which a dye is injected into the arteries of your heart. This allows the cardiologist to see exactly where and how severe blockages in your arteries are.

Around half the people who have blocked coronary arteries are offered angioplasty. The rest are better treated with bypass surgery. Diabetic patients often do better with coronary artery bypass grafting and there are instances when technical difficulties make bypass surgery the better option.

Even relatively mild angina which is controlled by medication can be relieved by angioplasty. It is a question of weighing up the risks, benefits and costs of this procedure rather than remaining on medication and altering your lifestyle.

Remember that lifestyle changes must be made even after angioplasty or bypass surgery. In particular, you must never smoke again.

Prevention

For most people clinically important atherosclerosis can be prevented or markedly retarded by means of lifestyle changes alone. In some, cholesterol-lowering medication may be required; and in a few it may be impossible at the present time.

Lifestyle changes involve:

  • an appropriate diet
  • regular exercise
  • the elimination of harmful substances

Diet and exercise work together in a synergistic fashion and can also help reduce stress which can contribute to clinical complications.

The principles are easy to understand but putting these into practice can be difficult in developed countries. It requires commitment and understanding plus a refusal to be misled by a host of popular fads which promote specific foods or substances as the secret of success. These are almost universally ineffective and are occasionally harmful.

Principles of a healthy diet

Obesity contributes to atherosclerosis directly and indirectly. Most South Africans are overweight. In such people, loss of weight is important in lowering blood pressure, reducing the risk of diabetes mellitus in predisposed individuals and in reducing triglyceride and raising "good" HDL-cholesterol levels. These changes are strongly protective against atherosclerosis and its complications.

Loss of weight is achieved by reducing energy intake, especially energy contained in fat, and by increasing energy expenditure through regular exercise. In addition to fat, over-indulgence in simple carbohydrates – e.g. sugar, sweets and many soft drinks – also contributes to obesity.

The worst way to approach weight loss is by means of crash diets. These result in large weight fluctuations, called cycling, and rarely have benefit.

Besides weight normalisation, it is desirable to cut down on saturated fat, cholesterol and trans fatty acid intake. This can be accomplished by reducing the consumption of:

  • red meats, the skin of poultry and, especially, processed meats such as salamis and polony
  • full-cream dairy products such as full-cream milk, cream, most cheeses and yoghurts, many pastries and desserts
  • eggs or egg-based products in desserts, pastries and pies
  • fried foods, especially those cooked in repeatedly used oils
  • commercially produced cookies, crisps and crackers and baked products that contain hard "brick" margarine

Antioxidants and other food 'fads'

  • These vary from mildly useful to neutral to positively harmful. The most authoritative opinion is that there is no solid evidence in favour of antioxidant vitamin supplementation and harmful effects may occur.
  • Soluble fibre contained in fruits, wholewheat bread and certain oats has a variety of health promoting effects and a mildly cholesterol-lowering action.
  • Garlic has a controversial mildly beneficial effect on cholesterol levels .with the balance of opinion being against a beneficial effect. There is a possibility that garlic may also influence blood platelets and clotting favourably. 
  • Fat-free substitutes in foods can assist with weight loss and lowering of cholesterol and triglycerides, but can have other side effects.

The bottomline is this: an appropriate mixed diet with a healthy balance of fruit and vegetables and a reduction in saturated fat, regular exercise, normalisation of weight or at least some weight reduction in obese persons and avoidance of smoking will contribute 90% powerfully to the lowering of atherosclerotic risk.

Additional measures can make a small contribution but some are actually harmful – especially if they divert attention from the known effective means of prevention.

Most people will need the advice of a qualified dietician, a clear strategy and goals, regular monitoring and some form of support – until good practice becomes habitual.

Many of the foods mentioned are also high in salt and most Westernised individuals eat salt far in excess of need, which may promote high blood pressure in susceptible people and have other adverse effects.

Exercise

The evidence is overwhelming that regular aerobic exercise at virtually any age reduces atherosclerosis and its complications. It has a variety of directly beneficial effects as well as being an important component of weight normalisation.

The baseline should be set at five three hours of aerobic activity dispersed throughout the week, such as walking, cycling, jogging, aerobics, rowing or swimming. This can be varied to prevent boredom and to maximise effect, and can be adjusted in intensity and duration according to the health status, age and objectives of the individual. The addition of mild to moderate resistance training can help strengthen muscles and bone and promote weight loss.

Once again, the advice of a professional trainer is useful, especially in the early stages. The support of a family member, friend or group is very valuable.

Consult your doctor if you have any symptoms or conc erns over your health status. It is vital to start slowly: in the long run it will do far more good than a crash start.

Avoidance of harmful substances

First and foremost among these is cigarette smoking. Risk of coronary artery disease is at least doubled in most smokers and often more than when it interacts with other risk factors, elevating risk 10-fold or more. Besides heart disease, smoking promotes lung disorders such as emphysema and causes cancer.

The good news is that the risk of vascular disease drops rapidly after stopping smoking, reaching baseline within two years. Professional help and support is again important, especially since stopping smoking promotes weight gain. Thus exercise and diet are part of the anti-smoking programme.

Excessive alcohol consumption, e.g. over 10 tots per week, can induce atherosclerosis and hypertension in susceptible individuals and harm the liver. Moderate regular alcohol consumption may be beneficial.Epidemiologic studies indicate that wine may reduce risk of atherosclerosis and cardiovascular disease. Binge drinking is definitely risky and should be strongly avoided.ui

When to call your doctor

Because atherosclerosis is such an insidious condition, and starts at an early age, the best approach is one of prevention. A screening fasting lipogram will quickly identify any patient at risk, along with blood pressure and diabetes assessments.

The Clinical Guidelines recently announced by the South African Heart Association and Lipids and Atherosclerosis Society of Southern Africa recommend that all young adults be assessed at least once for the risk or presence of atherosclerotic vascular disease. This can be done as part of a normal medical visit.

This provides you with the essential information (e.g. blood pressure, total, LDL- and HDL-cholesterol levels, triglyceride concentration, body weight and height, fasting glucose value) to modify your lifestyle so as to promote health and reduce risk. Occasionally, the results may indicate the need for further investigation and more vigorous treatment, but generally a five year follow-up is recommended even for relatively low-risk individuals. In older people, above 60 years, more frequent examination is desirable.

In addition to such baseline examination, you should consult your doctor under the following circumstances:

  • If you experience symptoms for the first time of a possible atherosclerosis-related medical condition. These include: chest pain, undue breathlessness, tingling or numbness in your arms, palpitations, visual, speech or coordination disturbances, any unexplained loss of consciousness or mental confusion, pain in your legs when walking, which improves on rest, undue fatigue or excessive thirst, or passing urine frequently.
  • If you have an increase in any of the above symptoms.
  • If you are at increased risk through family history, poor lifestyle habits, obesity or the presence of diabetes mellitus (or, more rarely, some other predisposing condition). If you develop discolouration or unusual skin sores in your legs or feet. This may indicate severe atherosclerosis and possibly a circulatory blockage that needs treatment to prevent gangrene.

It is possible to have atherosclerosis for many years without having symptoms and sometimes the clinical complications are worse than may be expected from the degree of atherosclerosis present. Despite these difficulties, a careful medical work-up provides the important information required for effective prevention and treatment.

Reviewed by: Prof David Marais, head of UCT’s and Groote Schuur Hospital’s Lipid Clinic, September 2010.

 
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