Heart is the most vital organ in the body. Heart weighs 340 grams and is red brown in colour. The heart is a pear shaped organ about 15 centimetres long and 10 centimetres width in base.

Heart is a hard working, four chambered pump- actually two pumps, one to move blood to the lungs, the other to push the blood into the body. Everyday in 24 hours heart pumps blood through 90,000 kilometres of blood vessels. The total blood pumped in 24 hours can fill a 15100 litres tank.

No muscle in body is as strong as heart muscle except human uterus. Human uterus only works occasionally during child birth while heart muscle works till death - sometimes 100 years. In eighty ninety year of life heart pumps about 600,000 tonnes of blood enough to fill a small tank.

Calf muscles of a Marathon runner are very strong. But if these muscles work like heart muscles, they will be turned into a jelly in minutes.

How does heart get nourishment?

Heart gets nourishment from blood. Though the weight of heart is 1/200 of body weight still it requires 1/20 of total blood supply. That means heart consumes about ten times more nourishment required by body’s other organs.

But the peculiarity of nourishment is, heart does not consume from the blood present in four chambers of heart.  Heart gets nourishment from the two coronary arteries. Coronary arteries are like branches of trees. Their main trunk  measures the size of a little finger. If the blood supply to the coronary arteries is hampered, that leads to heart attack. Heart attack is the single largest cause of death.