How does a healthy heart work?
The heart is part of the circulatory system, which
carries blood throughout the body. The heart is made of muscle and works like a
pump to keep the blood moving through the blood vessels (arteries, veins, and capillaries).
The heart has four chambers—the right atrium and the
left atrium (plural: atria) on top and the right and left ventricles on the
bottom. The heart is divided by a solid wall called the septum into two sides:
the right side sends blood to the lungs to get oxygen, while the left side of
the heart moves oxygen-rich blood to the rest of the body through the aorta (the main artery in the heart). (image to right: inside of the heart).
Blood enters the heart through the right atrium and
moves to the right ventricle, where it then moves through the pulmonary artery
to the lungs to pick up oxygen. The newly oxygenated blood then enters the heart
through the left atrium and moves to the left ventricle, where it is sent
through the aorta to the rest of the body.
There are also four valves in the heart, which open and close to allow blood to move through the chambers:
- The aortic valve, located on the left side of the heart, between the aorta and the left ventricle
- The mitral valve, located between the left ventricle and the left atrium
- The pulmonary valve, located on the right side of the heart between the
right ventricle and the pulmonary artery (the blood vessel that carries blood to the lungs)
- The tricuspid valve, located on the right side of the heart between the
right ventricle and the right atrium
Blood vessels—arteries, veins, and capillaries--are also involved in helping blood flow:
- The pulmonary artery moves blood from the heart to the lungs, where it picks up oxygen.
- Pulmonary veins move blood from the lungs to the heart’s left side,
where it can be transported to the rest of the body.
- The aorta sends newly oxygenated blood from the left side of the heart to the rest of the body.
- The inferior vena cava and superior vena cava bring blood back to the heart to get new oxygen.
- The coronary arteries take blood and oxygen from the aorta to the heart muscle itself.
(image to right: exterior of the heart)
What are pediatric congenital heart defects?
The word congenital means that a condition is present
when a baby is born. If a baby is born with a heart defect, the heart is not
working properly, usually because there is something wrong (defective) with the
valves or the blood vessels around the heart. The defect can keep blood from
flowing normally and can affect heart development. Congenital heart defects can
be simple or complex. There are one million adults and children in the United
States who have congenital heart defects.