The heart is a vital human organ approximately the size of a fist. Its purpose is to deliver oxygen-rich blood throughout the body. Each time the heart "beats" it is expanding to fill with blood and then contracting to force blood through the arteries to all of the body's organs and extremities.
In essence, the heart is a pump, and like other mechanical pumps, it can become clogged, leak, break down and require repair.
The heart's four valves play a vital role with every heartbeat. When the heart's ventricles fill with blood, the mitral and tricuspid valves automatically shut, preventing blood from flowing backward into the atria. As the ventricles contract, the pulmonic and aortic valves open, allowing blood to be "pumped" through these open valves into the body.
When the ventricles finish their contraction, the pulmonic and aortic valves shut, preventing blood from flowing back into the ventricles.
Did you know the heart repeats this whole process an average of 70 times per minute, 4,200 times per hour, and more than 100,000 times per day?