The heart is a tireless live motor

The body that causes blood in motion, is the heart. Knowing already the structure and the basic laws of motion of blood, we can experience now with the activities of this great body.
Alone heart is reduced on average 70-75 times per minute. Initially reduced the Atria. Each of them sends into your ventricle another portion of blood. Then reduced the ventricles, squeezing contained within them now the blood. The valves between the Atria and ventricles while tensing up and not let the blood back into the heart chambers. Therefore, the blood rushes through the opening valves pulmonary artery (from the right ventricle and the aorta (from the left ventricle), in each of them comes 65-70 ml of blood, i.e. 1/3 Cup. Following this, the heart muscle is relaxed. Now the pressure inside the ventricles becomes incomparably less than in the aorta and the pulmonary artery, stretched thrown at them with great force blood. So the blood would rush back to the ventricles, but the valve of aorta and pulmonary artery slam and don't let her there. The blood goes down the vessels.
When the sea is reduced, it becomes dense; compare this with a voltage skeletal muscles, such as biceps shoulder. Reducing heart just turns, pressed the tip to the chest wall. Therefore, putting a hand to his chest, we can in the field below left nipple to feel a heart impetus with each heartbeat. Precisely because the contraction of the heart is accompanied like a "kick" from inside the chest wall, we say "heart beats" and reduced it called the strike. In science as the contraction of the heart is called systole and relaxation - diastole.
If you count the number of heart beats, for example by pulse on the hand, while you put your ear to the field of cardiac impulse, you can be sure that with each heartbeat heard two sounds: the so-TA, TA, TA. What these sounds and why their two with each contraction of the heart? The sound of these depend mainly on closing valves. When the ventricles contract and is rapidly growing pressure, they close the valves on the border with the Atria. When the ventricles begin to relax, shut the valve of aorta and the pulmonary artery. Originate here, sounds, or heart sounds.
If a person falls ill with rheumatism and his heart becomes involved in a painful process, valves may be damaged. Now they slam unsteadily, and of the blood through a narrow slit is slipping back into the atrium or (if the damaged valve of aorta) in the ventricle. This is the reverse movement of blood through a narrow gap creates noise that enters the heart sounds. Violation of the integrity of the valve impedes the circulation of the blood. In such cases they say about heart disease.
Often in life rheumatism call every appearance of pain in the joints. This is not true. Flash rheumatism occur very rapidly. Rheumatic fever is a severe disease with high fever, different from other joint diseases the fact that he, as they say, often not only "licks the joints, but bites heart." Infection that causes rheumatic fever, breeds most commonly in patients tonsils. Therefore it is necessary to struggle with angina, tempered, delete if necessary diseased tonsils and then we will win rheumatism. The infection can nest and carious teeth. Not going to the dentist, we sometimes get much more difficult.