YOUNG blood vessels are flexible and elastic, but unavoidably as one grows older ,arteries harden and thicken mainly from fats circulated to all parts of the body through blood accumulating in the inner wall of the vessels. Atherosclerosis, the result of this accumulation of fats, causes blood vessels to lose their elasticity and harden and ducts to become narrower affecting normal blood supply to the brain, heart and other parts of the body.
Atherosclerosis is a major cause of coronary heart disease.
There are eight major "risk factors" which lead to coronary heart disease:
Heredity. If parents, especially the father, dies at a young age of coronary heart disease, their childred have a higher risk of contracting coronary heart disease.
Hypertension. About 30 to 40 per cent of Hong Kong patients of coronary heart disease also have hypertension-which increases the accumulation of fats in the arterial walls causing a hardening of the blood vessels. Hypertension also damages the inner wall of the arteries which can lead to blood clots and blockage.
Diabetes. Diabetics have a 2 to 6 times greater chance of contracting coronary heart disease.
High concentration of blood cholesterol. Passing middle age con bring high concentrations of blood cholesterol in the blood vessels leading to their hardening and blockage. A high content of cholesterol is found in lard, butter, pig's brain, liver, kidney, heart, egg yolk, oyster, crab, shrimp, clam, cuttlefish, milk, cream, cheese, etc. Foods containing saturated fats (beef, mutton, sausage, coconut oil, cream, etc),which will transform into cholesterol after metabolism, also lead to an increase of blood cholesterol.
Smoking. Smokers stand a 2 to 10 times greater chance of contracting coronary heart disease. Nicotine raises the blood pressure and hastens the pulse rate. It can also stimulated the secretion of adrenaline which indirectly leads to the narrowing of the vessels.
Being overweight. Chances of contracting coronary heart disease increase when a person is 30 per cent over normal body weight. Being overweight is closely related to hypertension, diabetes and high cholesterol. Middle-aged people should eat more vegetables, fresh fruits and bean curd ,while limiting meat intake to fish ,lean meat and poultry.
Lack of exercise. Regular exercise reduces cholesterol in the blood and body weight, creating an increase in 'high density lipoprotein' in the blood. The most effective exercises (swimming, jogging, cycling, etc.) must be done on a regular basis.
Tension. Tension causes adrenaline secretion and an increased pulse rate leading to higher blood pressure. People who are chronically tense are at a higher risk of contracting coronary heart disease.
Angina Pectoris(heart pain).There are two kinds of angina. Stable angina pectoris is predictable and occurs when a person undergoes physical activities such as walking up stairs or a steep incline. Occasionally it occurs when a person is agitated or after full meals. When it does, you should stop all activities and rest until chest pain symptoms go away.
Unstable angina pectoris can occur while at rest, when at sleep for during physical activities that usually do not cause discomfort. This is serious and most sufferers have to be admitted to hospital. Unstable angina pectoris may be a sign of myocardial infarction.
Myocardial infarction(sudden heart attack) is usually caused by coronary thrombosis-a blood clot. If this occurs ,the sufferer is admitted to hospital.
For people with serious coronary heart disease, cardiac catheterisation is a very significant examination to accurately locate the blocked part of the blood vessels .Not all patients of coronary heart disease need to undergo this examination-called angiography and under taken so as to formulate proper treatment.
Medical treatment. The function of medication is to reduce the consumption of or improve the supply of oxygen to the heart and will be administered to lower the heart beat, decrease the blood pressure, or expand the coronary artery so that narrowed blood vessels can be dilated.
There are two major categories of heart operation. The bridging procedure from aorta to the coronary artery requires general anaesthesia, after which a healthy vein is removed from the patient's leg of elsewhere and then re-connected to bypass the blocked blood vessel.
Alternatively, during angioplasty a cardiac catheter with a "balloon" is inserted into the coronary artery and guided to the narrowed or blocked part of the blood vessel, after which the "balloon" is inflated and expands the obstructed part of the artery allowing blood flow to resume.
To prevent coronary heart disease: Have regular heart check ups. With respect to hypertension, diabetes, high blood cholesterol-actively rectify the situation by treating the disease immediately. Stop smoking. Maintain an appropriate lifestyle regimen and improve diet. Take reasonable time for rest, entertainment and sports and keep proper body weight.

Information for Health is Wealth is provided by doctors and health care professionals of the Hong Kong Medical Association (co-ordinated by Administration and Support Group, Personnel Services Branch, Hong Kong Police).They look forward to receiving (and will try to answer in this Column)any questions you have on coronary heart disease. Please fax: 2865-4799.