The term coronary heart disease covers a group of clinical syndromes arising particularly from failure of the coronary arteries to supply sufficient blood to the heart. They include angina pectoris, coronary thrombosis or heart attack and sudden death without infarction.
There has been a marked increase in the incidence of heart disease in recent years. Heart attacks have become the number one killer in western countries. They rank third in India , after tuberculosis and infections. The disease affects people of all ages and both sexes, although it is more common in men than in women, especially in those aged 40-60 years.
The heart, the most vital organ in the body, is a muscle about the size of a clenched fist. It starts working even before birth inside the womb. Weighing about 300 grams, it pumps about 4,300 gallons of blood every day through the body and supplies oxygen and nourishment to all the organs.
It beats 1,00,000 times a day, continually pumping the blood through more than 60,000 miles of tiny blood vessels. The heart, in turn, needs blood for its nourishment, which is supplied by coronary arteries.
In the event of narrowing or hardening of the arteries on account of their getting plugged with fatty substances, the flow of blood is restricted. The heart then does not get sufficient oxygen. This condition is known as ischaemia of the heart or angina pectoris, which is a latin word meaning pain in the chest.
It is actually a cry of the heart for more blood. In this condition, exercise or excitement provokes severe chest pain and so limits the patient’s physical activity. It serves as a warning to slow down and prompt preventive measures will prevent a heart attack.
If the narrowed arteries get blocked due to a clot or thrombus inside them, causing death of that portion of the heart which depends upon the choked arteries, it is called a heart attack or coronary thrombosis. It may lead to death or heal, leaving a scar.
Patients with healed lesions may be severely disabled or may be able to resume normal life with restrictions in their physical activities. A high proportion of cases of sudden death occur in persons who have had angina pectoris or coronary thrombosis.
The coronary arteries get narrowed due to various chemical deposits on their inner linings. These are caused by inherited or acquired defects in the metabolic processes of the body with regard to intake and absorption of various substances.
A diet rich in fatty foods, especially animal fats, causes fatty substances to settle in the coronary arteries, thus blocking and narrowing them. The process of silting up of arteries is known as arterioscelrosis and is a major degenerative change affecting the circulatory system.
Symptoms
A common symptom of heart disease is shortness of breath, which is caused by the blood being deprived of the proper account of oxygen. Another common symptom is chest pain or pain down either arm. Other symptoms are palpitation, fainting, emotional instability, cold hand and feet, frequent perspiration and fatigue.
All these symptoms may be caused by many other disorders. Appropriate tests and studies are, therefore, essential to establish the true nature of these symptoms.
Causes
The basic causes of heart disease are wrong food habits, faulty style of living and various stresses. The famous Framingham Heart Study of the National Heart and Lung Institutes identified seven major risk factors in coronary heart disease. These are:
(i) elevated blood levels of cholesterol, triglycerides and other fatty substances
(ii) elevated blood pressure
(iii) elevated blood uric acid levels (mainly caused by a high protein diet)
(iv) certain metabolic disorders, notably diabetes
(v) obesity
(vi) smoking, and
(vii) lack of physical exercise.
Any one or a combination of these risk factors can contribute to heart disease. Most of them are of dietary origin.
These risk factors can be controlled by changing one’s life style and re-adjusting the diet. Constant worry and tension stimulates the adrenal glands to produce more adrenaline and cartisons. This also contributes to constricted arteries, high blood pressure and increased work for the heart.