We see and hear about hearts everywhere. A long time ago, people even thought that their emotions came from their hearts, maybe because the heart beats faster when a person is scared or excited. Now we know that emotions come from the brain , and in this case, the brain tells the heart to speed up. So what's the heart up to, then? How does it keep busy? What does it look like? Let's find out. Your heart is really a muscle.
It's located a little to the left of the middle of your chest, and it's about the size of your fist. There are lots of muscles all over your body — in your arms, in your legs, in your back, even in your behind. But the heart muscle is special because of what it does. The heart sends blood around your body. The blood provides your body with the oxygen and nutrients it needs. It also carries away waste. Your heart is sort of like a pump, or two pumps in one. The right side of your heart receives blood from the body and pumps it to the lungs.
The left side of the heart does the exact opposite: It receives blood from the lungs and pumps it out to the body. How does the heart beat? Before each beat, your heart fills with blood. Then its muscle contracts to squirt the blood along. When the heart contracts, it squeezes — try squeezing your hand into a fist. That's sort of like what your heart does so it can squirt out the blood. Your heart does this all day and all night, all the time.
The heart is one hard worker! The heart is made up of four different blood-filled areas, and each of these areas is called a chamber. There are two chambers on each side of the heart. One chamber is on the top and one chamber is on the bottom.
The two chambers on top are called the atria say: AY-tree-uh. If you're talking only about one, call it an atrium. The atria are the chambers that fill with the blood returning to the heart from the body and lungs. The heart has a left atrium and a right atrium. The two chambers on the bottom are called the ventricles say: VEN-trih-kulz. The heart has a left ventricle and a right ventricle.
Their job is to squirt out the blood to the body and lungs. Running down the middle of the heart is a thick wall of muscle called the septum say: SEP-tum. The septum's job is to separate the left side and the right side of the heart. The atria and ventricles work as a team — the atria fill with blood, then dump it into the ventricles.
The ventricles then squeeze, pumping blood out of the heart. Innocent heart murmurs usually do not need to be treated. If your heart murmur is caused by an underlying condition, such as high blood pressure, your doctor will treat that condition. If your heart murmur is caused by disease of the valve itself intrinsic valve disease or other heart defects, medicines or surgery may be needed. Doctors used to give anyone with a heart murmur antibiotic medicines before a dental or surgical procedure to prevent infection in your heart valves.
Some of these procedures may cause bacteria to enter the bloodstream, which can lead to infection. Today, most doctors do not recommend routine antibiotics unless the murmur is caused by intrinsic valve disease. Talk to your doctor or dentist for current guidelines. Your doctor may prescribe certain medicines, depending on the underlying cause of your heart murmur. In some patients, surgery may be needed to repair a heart defect or repair or replace a damaged heart valve.
During inspiration breathing in there is slightly increased blood return to the right side of the heart, which causes the pulmonary valve to stay open slightly longer than the aortic valve. Due to this, the naming convention is to divide the second sound into two second sounds, A2 aortic , and P2 pulmonary. The time between A2 and P2 is variable depending on the respiratory rate, but the split is generally only prominent in children during inspiration. In adults and during expiration, the split is usually not long enough to suggest two sounds.
Abnormal heart sounds may indicate problems with the health of the valves. Murmurs may also be caused by valve stenosis improper opening and cardiac shunts, a severe condition in which a defect in the septum allows blood to flow between both sides of the heart.
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