A major cause of heart disease is atherosclerosis, a disease of arteries in which plaques of cholesterol rich fat become deposited on the inner lining of the artery reducing the normal flow of blood. These plaques are called atheroma. Factors responsible for atherosclerosis include:

• Diet
• Smoking
• High Blood Pressure
• Family History

These web pages explain heart disease, how angina develops and how it can be treated.

Atherosclerosis affects medium sized arteries especially to the legs, brain and heart, causing gangrene, stroke and heart attacks. It may take several years to manifest itself and often follows years of unhealthy diet, smoking, uncontrolled diabetes and sedentary lifestyle.

Angina Pectoris
When coronary arteries become diseased by atherosclerosis, the blood supply to the heart is reduced, producing symptoms such as breathlessness and particularly tight squeezing pain across the front of the chest. Such symptoms occurring on exercise and relieved by rest constitute Angina Pectoris.

Coronary Thrombosis
Occasionally, a small clot of blood forms on an atheromatous plaque producing a sudden occlusion (blockage) of the artery - a condition called a coronary thrombosis. This sudden interruption of blood to part of the heart causes angina type pain which is not eased by rest and lasts several hours. This results in death of some heart muscle – known as a heart attack or myocardial infarction.

Similarly, a stroke occurs where the blood supply to the brain is interrupted and this tissue dies unfolding a wide range of symptoms depending on which part of the brain is affected. It may result in permanent damage or there may be some degree of recovery after intensive rehabilitation if this function can be transferred to another part of the brain.

TIA is similar to stroke but is of a temporary nature lasting up to 24 hours, resolving spontaneously. There may be loss of consciousness and confusion caused by a partial lack of oxygen to the brain via the diseased carotid arteries with plaques. TIAs are often a prelude to a major stroke and as such require detailed investigations and treatment to prevent a full blown event.

This condition is the result of blocked or occluded femoral arteries which may result in lack of oxygen to the muscles in the legs causing pain and cramp usually on exercise. At its worst, gangrene may result as the tissue dies and becomes infected after lack of oxygen. This condition is not uncommon in heavy smokers.

Risk Factors for Heart Disease

1. Unmodifiable risk for heart disease – things which cannot be changed

• Age, sex, family history of premature heart disease, race

2. Modifiable risk - which can potentially be targeted for change

• Smoking, high blood pressure, blood cholesterol levels, sedentary lifestyle, diabetes, obesity, diet, hyperlipidaemia

This is a well-known risk factor for lung disease but also for heart disease, vascular disease and, as mentioned previously, the flow of blood to the brain and its consequences. The risk occurs across many countries, races, males and females and increases with increasing cigarette use; however, the risk falls rapidly over time when people stop smoking.

Hypertension or high blood pressure, is a major risk factor for coronary heart disease and cerebrovascular disease (blood supply to the brain) and the formation of atherosclerosis. Therefore, corrective treatment of this condition is important in reducing the risk of cardiovascular disease.

Cholesterol is an essential body ingredient in the right amount and found in all human cells where it is needed to form essential steroid hormones. It is carried in the blood by lipoproteins of which there are two types - Low Density Lipoproteins (LDL) and High Density Lipoproteins (HDL). However, a diet high in saturated fats encourages cholesterol levels to rise and the excess can be deposited in the walls of arteries causing dangerous narrowing or atherosclerosis.

These are complexes where cholesterol and other fats or lipids are transported in the blood with proteins. LDLs contain relatively large amounts of cholesterol and transport lipids to muscle and fat stores. High levels of LDL are associated with atherosclerosis.

HDLs contain 50% protein and only 20% cholesterol and would appear to be protective against heart disease and stroke.

An association between a less active lifestyle and risk of coronary heart disease has been shown to be a risk factor. Therefore, increasing daily activity by walking and using stairs instead of lifts is beneficial in keeping a healthy circulation. However, those with angina will be unable to modify activity until treated.

Diabetic individuals are at high risk of cardiovascular disease due to increased blood glucose and lipid levels.

Excess weight in itself is a risk for heart disease as well as increasing blood pressure and cholesterol levels. Weight reduction is a primary aim to reduce the risk of severe consequences of heart disease along with other therapies and recommendations.

Diet
Modification can aid weight reduction and can also help to lower cholesterol levels.

Statins - Lipid Lowering agents used to reduce LDL and raise beneficial HDL cholesterol also reduce the progression of coronary atherosclerosis.

Aspirin - to reduce platelet aggregation, allowing blood to become less viscous.

Nitrates - dilate coronary arteries improving blood supply and reducing ischemic pain and are available as quick acting preparations

• Glyceryl trinitrate which is used under the tongue for rapid relief of angina pain
• Isosorbide dinitrate which is also used under the tongue for those requiring infrequent treatment. For a slower effect it can be taken by mouth for prophylaxis. It exerts its effect by metabolising to isosorbide mononitrate.
• Isosorbide Mononitrate used for angina prophylaxis and available as twice daily tablets and once daily tablet options. It is thought once daily dosing may improve patient compliance.
• Nitrate sprays, patches, intravenous and capsule formulations also available.

Beta Blockers - lower blood pressure by slowing the heart rate and improving exercise tolerance

Diuretics - used to rid the body of excess fluid and to reduce blood pressure

Following a heart attack and suitable treatment, some patients will go on for surgery to the coronary arteries. This procedure is called Coronary Artery Bypass Graft surgery (CABG) which involves bypassing the coronary arteries using pieces of saphenous vein from the leg. Similar surgery is sometimes used for patients who have severe impairments to their lifestyle from Angina.

Angioplasty is an increasingly used technique where the narrowed artery is dilated from the inside using specially designed long catheters passed into the coronary arteries via the leg arteries.