Heart Murmurs and Your Child

Many parents fear the worst when their child is diagnosed with a heart murmur, but this diagnosis is actually extremely common. In fact, many kids are found to have a heart murmur at some point during their lives. Most murmurs are not a cause for concern and do not affect the child's health at all.

What exactly is a heart murmur? By itself, the term heart murmur isn't a diagnosis of an illness or disorder. To better understand what it does mean, it's important to know how the heart works.

How the Heart Works
The normal heart has four chambers and four valves (which function like one-way doors). The two lower pumping chambers of the heart are called the ventricles, and the two upper filling chambers are the atria (singular is atrium).
Here's how blood moves in normal circulation:
Blood that returns from the body to the filling chamber on the right side (the right atrium) is low in oxygen.
This blood passes across a valve (the tricuspid valve) to the pumping chamber on the right side (the right ventricle) and then travels across the pulmonary valve to the lungs to receive oxygen.
The oxygen-enriched blood returns to the filling chamber on the left side (the left atrium), then across a valve (the mitral valve) to the pumping chamber on the left side (the left ventricle).
The blood is then pumped across the aortic valve out to the body through the aorta, a large blood vessel that carries blood to the smaller blood vessels in the body to deliver oxygen.
Using a stethoscope, a doctor examines the heart by listening to the sounds it makes. The familiar "lub-dub" sound of a normal heartbeat is caused by the closing sound of the valves as the heart squeezes to push blood through the body.

A heart murmur describes an extra sound in addition to the "lub-dub." Sometimes these extra sounds are simply the sound of normal blood flow moving through a normal heart. Other times, a murmur may be a sign of a heart problem.

Cholesterol and Your Child

Most parents probably don't think about what cholesterol means for their kids. But high levels of cholesterol are a major factor contributing to heart disease and stroke, and medical research shows that cardiovascular disease has its roots in childhood. And with the dramatic increase in childhood obesity, more and more kids are at risk.

Problems associated with high cholesterol generally don't show up for years, so making the connection between kids' health and cholesterol can be difficult. But it's important to know your child's cholesterol levels, especially if there's a family history of high cholesterol or premature heart disease.

Identifying high cholesterol now will let you and your doctor work together to make changes that will lower your child's risk of developing heart disease later.

About Cholesterol
Cholesterol is a waxy substance produced by the liver. It's one of the lipids, or fats, the body makes and is used to form cell membranes and some hormones.

If you never ate another bowl of ice cream or another cheeseburger, your body would have enough cholesterol to run smoothly. That's because the liver makes enough for healthy body function. In fact, the liver produces about 1,000 milligrams of cholesterol a day. The rest comes from the foods we eat.

Although vegetables, fruits, and grains don't have any cholesterol, these foods from animals do:

egg yolks
meat
poultry
seafood
dairy products (including milk, cheese, and ice cream)

Arrhythmias

An arrhythmia is an abnormal heart rhythm usually caused by an electrical "short circuit" in the heart.

The heart normally beats in a consistent pattern, but an arrhythmia can make it beat too slowly, too quickly, or irregularly. This can cause the heart muscle's pumping function to work erratically, which can lead to a variety of symptoms, including fatigue, dizziness, and chest pain.

What Causes Arrhythmias?
The heart has its own conduction system, or electrical system, that sends electrical signals around the heart, telling it when to contract and pump blood throughout the body. The electrical signals originate from a group of cells in the right atrium, called the sinus node. The sinus node functions as the heart's pacemaker and makes sure the heart is beating at a normal and consistent rate. The sinus node normally increases the heart rate in response to factors like exercise, emotions, and stress, and slows the heart rate during sleep.

However, sometimes the electrical signals flowing through the heart don't "communicate" properly with the heart muscle, and the heart can start beating in an abnormal pattern — an arrhythmia (also called dysrhythmia).

Arrhythmias can be temporary or permanent. They can be caused by several things, but also can occur for no apparent reason. Arrhythmias can be congenital (meaning kids are born with it), sometimes due to a birth defect of the heart but sometimes even when the heart has formed normally.

Other causes of arrhythmias in kids include chemical imbalances in the blood, infections, or other diseases that cause irritation or inflammation of the heart, medications (prescription or over-the-counter), and injuries to the heart from chest trauma or heart surgery. Other factors (such as illegal drugs, alcohol, tobacco, caffeine, stress, and some herbal remedies) also can cause arrhythmias.

Anemia

About Anemia
Anemia, one of the more common blood disorders, occurs when the level of healthy red blood cells (RBCs) in the body becomes too low. This can lead to health problems because RBCs contain hemoglobin, which carries oxygen to the body's tissues. Anemia can cause a variety of complications, including fatigue and stress on bodily organs.

Anemia can be caused by many things, but the three main bodily mechanisms that produce it are:

excessive destruction of RBCs
blood loss
inadequate production of RBCs
Among many other causes, anemia can result from inherited disorders, nutritional problems (such as an iron or vitamin deficiency), infections, some kinds of cancer, or exposure to a drug or toxin.

Anemia Caused by Destruction of RBCs
Hemolytic anemia occurs when red blood cells are being destroyed prematurely. (The normal lifespan of RBCs is 120 days; in hemolytic anemia, it's much shorter.) And the bone marrow (the soft, spongy tissue inside bones that makes new blood cells) simply can't keep up with the body's demand for new cells. This can happen for a variety of reasons. Sometimes, infections or certain medications — such as antibiotics or anti-seizure medicines — are to blame.

In autoimmune hemolytic anemia, the immune system mistakes RBCs for foreign invaders and begins destroying them. Other kids inherit defects in the red blood cells that lead to anemia; common forms of inherited hemolytic anemia include sickle cell anemia, thalassemia, glucose-6-phosphate dehydrogenase (G6PD) deficiency, and hereditary spherocytosis.

Sickle cell anemia is a severe form of anemia found most commonly in people of African heritage, although it can affect those of Middle Eastern and Mediterranean descent, as well as others. In this condition, the hemoglobin forms long rods when it gives up its oxygen, stretching red blood cells into abnormal sickle shapes. This leads to premature destruction of RBCs, resulting in chronically low levels of hemoglobin.

These abnormal red cells can clog small blood vessels, leading to recurring episodes of pain, as well as problems that can affect virtually every other organ system in the body. About 1 out of every 500 African-American children is born with this form of anemia.
Thalassemia, which usually affects people of Mediterranean, African, and Southeast Asian descent, is marked by abnormal and short-lived RBCs. Thalassemia major, also called Cooley's anemia, is a severe form of anemia in which RBCs are rapidly destroyed and iron is deposited in the vital organs. Thalassemia minor results in less severe anemia.
Glucose-6-phosphate dehydrogenase (G6PD) deficiency most commonly affects males of African heritage, although it has been found in many other groups of people. With this condition the RBCs either do not make enough of the enzyme G6PD or the enzyme that is produced is abnormal and doesn't work well. When someone born with this deficiency has an infection, takes certain medicines, or is exposed to specific substances, the body's RBCs suffer extra stress. Without adequate G6PD to protect them, many red blood cells are destroyed prematurely.
Hereditary spherocytosis is a genetic disorder of the RBC's membrane that can cause anemia, jaundice (yellow-tinged skin), and enlargement of the spleen. The RBCs have a smaller surface area than normal red blood cells, which can cause them to break open easily. A family history increases the risk for this disorder, which is most common in people of northern European descent but can affect all races.

Alpha Thalassemia

Thalassemias
Thalassemias are a group of blood disorders that affect the way the body makes hemoglobin, a protein found in red blood cells that is responsible for carrying oxygen throughout the body.

The body contains more red blood cells than any other type of cell, and each has a life span of about 4 months. Each day, the body produces new red blood cells to replace those that die or are lost from the body.

With a thalassemia, the red blood cells are destroyed at a faster rate, leading to anemia, a condition that can cause fatigue and other complications.

Thalassemias are inherited conditions — they're carried in the genes and passed on from parents to children. People who are carriers of a thalassemia gene show no thalassemia symptoms and might not know they're carriers. If both parents are carriers, they can pass the disease to their kids. Thalassemias are not contagious.

While there are many different types of thalassemias, the main two are:

Alpha thalassemia: when the body has a problem producing alpha globin
Beta thalassemia: when the body has a problem producing beta globin
When the gene that controls the production of either of these proteins is missing or mutated, it results in that type of thalassemia.

About Alpha Thalassemia

Alpha thalassemia occurs when the gene that controls the making of alpha globins is absent or defective. It can be mild to severe and is most commonly found in people of African, Middle Eastern, Chinese, Southeast Asian, and, occasionally, Mediterranean descent.

Some children with alpha thalassemia have no symptoms and may require no treatment. Others with more severe cases need regular blood transfusions to treat anemia and other symptoms.

A child can only get alpha thalassemia by inheriting it from his or her parents. Genes are "building blocks" that play an important role in determining physical traits and many other things about us.

Humans are made up of trillions of cells that form the structure of our bodies and carry out specialized jobs like taking nutrients from food and turning them into energy. Red blood cells, which contain hemoglobin, deliver oxygen to all parts of the body.

All cells have a nucleus at their center, which is kind of like the brain or "command post" of the cell. The nucleus directs the cell, telling it to grow, mature, divide, or die. The nucleus contains DNA (deoxyribonucleic acid), a long, spiral-shaped molecule that stores the genes that determine hair color, eye color, whether or not a person is right- or left-handed, and many more traits. DNA, along with genes and the information they contain, is passed down from parents to their children during reproduction.

Each cell has many DNA molecules, but because cells are very small and DNA molecules are long, the DNA is packaged very tightly in each cell. These packages of DNA are called chromosomes, and each cell has 46 of them. Each package is arranged into 23 pairs — with one of each pair coming from the mother and one from the father. When a child has alpha thalassemia, there is a mutation in chromosome 16.

Alpha globin is made on chromosome 16. So, if any gene that tells chromosome 16 to produce alpha globin is missing or mutated, less alpha globin is made. This affects hemoglobin and decreases the ability of red blood cells to transport oxygen around the body.