The existence of the heart was well known to the Greeks, who gave it the name kardia, still surviving in modern words such as cardiac and tachycardia. Aristotle believed that the heart was the seat of the soul and the centre of man.

Romans modified kardia to cor, the latter word still surviving in “cordial greetings”. The old Teutonic word herton was also derived from cor and gives us heart via the medieval heorte.

The heart has long been synonymous with love and Valentine’s Day. Sure, you know how to steal hearts, win hearts, and break hearts. But how much do you really know about your heart and how it works? Read on to your heart’s content!

• Put your hand on your heart. Did you place your hand on the left side of your chest? Many people do, but the heart is actually located almost in the centre of the chest, between the lungs. It’s tipped slightly so that a part of it sticks out and taps against the left side of the chest, which is what makes it seem as though it is located there.

• Hold out your hand and make a fist. If you’re a kid, your heart is about the same size as your fist, and if you’re an adult, it’s about the same size as two fists. An adult woman’s heart weighs about 225gm (8 ounces), a man’s about 285gm (10 ounces).

• Your heart beats about 100,000 times in one day and about 35 million times in a year. During an average lifetime, the human heart will beat more than 2.5 billion times.

• Give a tennis ball a good, hard squeeze. You’re using about the same amount of force your heart uses to pump blood out to the body. Even at rest, the muscles of the heart work hard - twice as hard as the leg muscles of a person sprinting.

• Feel your pulse by placing two fingers at pulse points on your neck or wrists. The pulse you feel is blood stopping and starting as it moves through your arteries. As a kid, your resting pulse might range from 90 to 120 beats per minute. As an adult, your pulse rate slows to an average of 72 beats per minute.

• The aorta, the largest artery in the body, is almost the diameter of a garden hose. Capilliaries, on the other hand, are so small that it takes ten of them to equal the thickness of a human hair.

• Your body has about 5.6 litres (6 quarts) of blood. This 5.6 litres of blood circulates through the body three times every minute. In one day, the blood travels a total of 19,000km (12,000 miles) - that’s four times the distance across the US from coast to coast.

• The heart pumps about 1 million barrels of blood during an average lifetime - that’s enough to fill more than three super-tankers.

• Lub-DUB, lub-DUB, lub-DUB. Sound familiar? If you listen to your heart beat, you’ll hear two sounds. These “lub” and “DUB” sounds are made by the heart valves as they open and close.

• Your system of blood vessels – arteries, veins and capilliaries – is over 60,000 miles long. That’s long enough to go around the world more than twice!

• Blood is about 78 per cent water

• The electrocardiograph (ECG) was invented in 1902 by Dutch physiologist Willem Einthoven. This test is still used to evaluate the heart’s rate and rhythm.

• The first heart specialists emerged after World War I.

Want to listen to a heartbeat? http://www.fi.edu/biosci/monitor/heartbeat.html

Pulse rate or heart beat calculator helps you to find out the average pulse rate or heart beat per minute. You can find average pulse rate for different ages of human life cycle right from mothers womb to a new born baby, child’s first, second, and third year, to teen, adult and old age. Find normal heart rates for your age & gender at http://www.medindia.net/patients/calculators/pulse_chart.asp

Dr Christiaan Barnard performed the world’s first heart transplant operation on 3rd December, 1967 in an operation, assisted by his brother, Marius Barnard, lasting nine hours and using a team of thirty persons. The patient, was 55 years old, the transplant heart came from a young woman, killed in a road accident. The patient survived the operation and lived for eighteen days, before succumbing to pneumonia induced by the immunosuppressive drugs he was taking.

Barnard continued to perform heart transplants: a transplant operation was conducted on 2nd January 1968, and the patient, Philip Blaiberg, survived for 19 months. Mrs Dorothy Fisher was given a new heart in 1969 and became the longest surviving patient, she lived for 24 years after the transplant.

Barnard retired from medical practice in 1983 at the age of 61 after developing rheumatoid arthritis affecting his hands. Christiaan Barnard died whilst on holiday in Cyprus, leaving behind five children. Early reports claimed that he had died of a heart attack, although an autopsy showed his death to be caused by an acute asthma attack.

Recent research has revealed that your heart does have feelings and contains brain-like cells that have a form of memory. In fact, your heart reacts to situations faster that your brain. Some people who’ve received transplanted organs have reported changes in taste and habits that mimic those of their donor. So perhaps you can die of a broken heart after all?