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Health Information For Parents
The heart is a pump, usually beating about 60 to 100 times per minute. With each heartbeat, the heart sends blood throughout our bodies, carrying oxygen to every cell. After delivering the oxygen, the blood returns to the heart. The heart then sends the blood to the lungs to pick up more oxygen. This cycle repeats over and over again.
The circulatory system is made up of blood vessels that carry blood away from and towards the heart. Arteries carry blood away from the heart and veins carry blood back to the heart.
The circulatory system carries oxygen, nutrients, and
to cells, and removes waste products, like carbon dioxide. These roadways travel in one direction only, to keep things going where they should.
The heart has four chambers — two on top and two on bottom:
The atria are separated from the ventricles by the atrioventricular valves:
Two valves also separate the ventricles from the large blood vessels that carry blood leaving the heart:
Two pathways come from the heart:
In pulmonary circulation:
In systemic circulation:
At each body part, a network of tiny blood vessels called capillaries connects the very small artery branches to very small veins. The capillaries have very thin walls, and through them, nutrients and oxygen are delivered to the cells. Waste products are brought into the capillaries.
Capillaries then lead into small veins. Small veins lead to larger and larger veins as the blood approaches the heart. Valves in the veins keep blood flowing in the correct direction. Two large veins that lead into the heart are the superior vena cava and inferior vena cava. (The terms superior and inferior don’t mean that one vein is better than the other, but that they’re located above and below the heart.)
Once the blood is back in the heart, it needs to re-enter the pulmonary circulation and go back to the lungs to drop off the carbon dioxide and pick up more oxygen.
The heart gets messages from the body that tell it when to pump more or less blood depending on a person’s needs. For example, when we’re sleeping, it pumps just enough to provide for the lower amounts of oxygen needed by our bodies at rest. But when we’re exercising, the heart pumps faster so that our muscles get more oxygen and can work harder.
How the heart beats is controlled by a system of electrical signals in the heart. The sinus (or sinoatrial) node is a small area of tissue in the wall of the right atrium. It sends out an electrical signal to start the contracting (pumping) of the heart muscle. This node is called the pacemaker of the heart because it sets the rate of the heartbeat and causes the rest of the heart to contract in its rhythm.
These electrical impulses make the atria contract first. Then the impulses travel down to the atrioventricular (or AV) node, which acts as a kind of relay station. From here, the electrical signal travels through the right and left ventricles, making them contract.
One complete heartbeat is made up of two phases:
To help keep your child’s heart healthy:
Let the doctor know if your child has any chest pain, trouble breathing, or dizzy or fainting spells; or if your child feels like the heart sometimes goes really fast or skips a beat.
Heart murmurs are very common, and most are no cause for concern and won’t affect a child’s health.
Mitral valve prolapse (MVP) is a very common heart condition, but it isn’t a critical heart problem or a sign of other serious medical conditions.
Atrial septal defect (ASD) â also known as a “hole in the heart” â is a type of congenital heart defect. Most ASDs are diagnosed and treated successfully.
Heart defects happen when there’s a problem with a baby’s heart development during pregnancy. Most heart defects can be treated during infancy.
A guide to medical terms about the heart and circulatory system. In an easy A-Z format, find definitions on heart defects, heart conditions, treatments, and more.
Your heart beats and sends oxygen throughout your entire body. Find out how it works and how heart problems can be fixed.
Arrhythmias are abnormal heartbeats usually caused by an electrical “short circuit” in the heart. Many are minor and not a significant health threat, but others can indicate a more serious problem.
Heart disease, also called cardiovascular disease, mainly affects older people. Find out more in this article for kids.
Everyone’s heart makes sounds, but some people have hearts that make more noise than others. Usually, however, these heart murmurs don’t mean anything is wrong. Find out more about these mysterious murmurs.
An arrhythmia is an abnormal heartbeat usually caused by an electrical “short circuit” in the heart. Many are minor and not a health threat, but some can indicate a more serious problem.
Atrial septal defect, or ASD, is a heart defect that some people are born with. Most ASDs are diagnosed and treated successfully with few or no complications.
Ventricular septal defect, or VSD, is a heart condition that a few teens can have. Find out what it is, how it happens, and what doctors do to correct it.
The heart and circulatory system (also called the cardiovascular system) make up the network that delivers blood to the body’s tissues.
Cardiomyopathy is when the heart muscle becomes weak and enlarged, which makes it difficult to pump blood through the body. Thereâs usually no cure for the condition in children, but it can be treated.
This minimally invasive procedure helps doctors performÂ diagnostic tests on the heart and even treat some heart conditions.
An interrupted aortic arch (IAA) is a rare heart condition in which the aorta doesnât form completely. Surgery must be done within the first few days of a babyâs life to close the gap in the aorta.
The foramen ovale is a normal opening between the upper two chambers of an unborn babyâs heart. It usually closes soon after the babyâs birth â when it doesn’t, it’s called a patent foramen ovale.
The ductus arteriosus is a blood vessel that connects two major arteries before birth and normally closes after a baby is born. If it stays open, the result is a condition called patent ductus arteriosus (PDA).
Supraventricular tachycardia is a type of abnormal heart rhythm in which the heart beats very quickly.
Learn how this amazing muscle pumps blood throughout the body.
Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
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