"HEART"

WORKING OF THE HEART AND ITS BLOOD SUPPLY

Heart is a muscular pump, made up of specialized muscles. The right half of the heart receives impure (deoxygenated) blood from the body and pumps it into the lungs. The left half of the heart receives pure (oxygenated) blood and pumps it to the rest of the body. The left half of the heart is stronger and thicker.
In order to function, the heart needs nourishment. The nourishment comes to the heart via blood which is supplied to the heart through two major coronary arteries : left and right coronary arteries. The left coronary artery again divides into two major branches (left anterior descending and left circumflex arteries), from which several smaller branches arise and supply the heart. Thus, there are three major arteries : left anterior descending artery, left circumflex artery and right coronary artery.

Coronary Artery Disease and Antherosclerosis

Atherosclerosis means hardening of the arteries. With advancing age, the arteries become stiff and there is deposition of fatty material in the walls of the arteries. When these changes are excessive and abnormal, the lumen of the artery is blocked, and blood flow is reduced. These changes also occur in coronary arteries, as a result, the arteries are blocked and blood supply to the heart muscles is impaired.
Because these changes occur throughout the body, a person may also have other arteries blocked and can have symptoms related to brain, kidney or limbs.

What predisposes to Coronary Artery Disease?


No definite cause is known. However, a number of risk factors are related to development and progression of coronary artery disease. Risk factors can be grouped into two categories :
(a) Non modifiable – These factors can not be changed by a person.
(b) Modifiable – These factors can be changed. (a) Non-modifiable risk factors -
There are 3 main non-modifiable risk factors
(i) Male Gender
(ii) Old Age
(iii) History of coronary artery disease in parents or siblings
(b)Modifiable risk factors
These factors are related to personal habits and lifestyle and can be modified. Modifiable risk factors can be grouped into Primary and Secondary risk factors
(i)Primary modifiable risk factors 1.Smoking 2. High blood pressure 3. Increased levels of cholesterol and other fats in blood 4.Diabetes – uncontrolled
(ii)Secondary modifiable risk factors 1.Obesity2. Lack of exercis3. Stress
More is the number of risk factors, greater are the chances of developing coronary artery disease.