Circulation of the blood around the body is essential as the blood takes nourishment to all your tissues and organs. It also transports waste materials to the lungs and kidneys, which then get rid of them from the body.
The heart is a muscular pump that pumps blood around your body. The two sides of the heart – the right side and the left side – work together. Blood from your muscles and organs enters the right side of your heart. The heart pumps the blood to the lungs where it takes up oxygen and removes the carbon dioxide it has been carrying. This oxygen-rich blood then enters the left side of the heart. From here it is pumped through the arteries to all parts of your body including to the heart muscle itself.
The movement of the blood through the heart is regulated by a system of valves. These make sure that the blood flows in the correct direction. There are four valves – one at the entrance (Tricuspid and Mitral valve in right and left side respectively) and one at the exit of each of the two pumping chambers (Aortic and Pulmonary valve in right and left side respectively).
The heart itself is a specialised muscular organ, which weighs 250 to 350 grams and beats approximately 100,000 times a day pumping around 5-6 litres of blood/min. Therefore the heart itself needs nutrients and blood supply to maintain the function. Tiny arteries called coronary arteries supply the blood to the heart muscle. These coronary arteries are the lifeline for the heart. The heart also has electrical conduction system inside which regulates the timing of the heart beat and act as a trigger for the heart to pump.