Congenital Heart Defects in Children – Symptoms and Causes
Understanding Heart Defects Present at Birth
Congenital heart defects are structural problems with the heart that babies are born with. These issues affect roughly eight out of every 1,000 infants born in the United States annually. That’s approximately 40,000 babies each year.
The severity of these conditions varies widely. Some defects may be so minor that they require no treatment, while others are complex and may need multiple surgeries over several years.
A congenital heart defect can involve abnormalities in any part of the heart structure, including:
- Heart chambers
- Heart valves
- Walls separating chambers
- Arteries and blood vessels
- Heart rhythm systems
These structural problems can disrupt the normal flow of blood and oxygen throughout the body. Some defects cause the heart to work harder than it should, which can lead to additional complications over time.
Signs and Symptoms
Not all heart defects cause noticeable symptoms right away. The signs depend on the type and severity of the defect:
In Newborns and Infants:
- Pale gray or blue skin color (cyanosis)
- Rapid breathing, especially during feeding
- Poor weight gain or feeding difficulties
- Swelling in the legs, abdomen, or areas around the eyes
- Shortness of breath during feeding
In Older Children:
- Getting tired easily during physical activity
- Shortness of breath during exercise
- Fainting during physical activity
- Swelling in the hands, ankles, or feet
- Heart murmurs (unusual heart sounds detected during check-ups)
Many heart defects are detected during routine medical check-ups when doctors hear an abnormal heart sound or murmur. While most heart murmurs are harmless or “innocent,” they sometimes indicate an underlying heart problem that requires further investigation.
Signs of Heart Defects
Serious heart defects present at birth are usually found shortly after birth or within the first few months of a baby’s life. You might notice these warning signs:
- Gray or blue color on the lips, tongue, or fingernails (may look different depending on skin tone)
- Fast breathing
- Swelling in the legs, belly, or around the eyes
- Breathing problems during feeding, which can lead to poor weight gain
Less serious heart defects might not be discovered until a child is older. In older children, signs include:
- Getting out of breath easily during play or exercise
- Unusual tiredness during physical activity
- Fainting while active
- Swelling in hands, ankles, or feet
When To Call a Doctor
Doctors often diagnose serious heart defects before birth or soon after a baby is born. If you notice any symptoms that suggest your child might have a heart problem, contact your child’s doctor right away.
Causes
Heart birth defects start during early pregnancy when a baby’s heart is developing. Around the first six weeks, the heart begins to form and beat. This is also when the major blood vessels connecting to the heart take shape.
During this critical time, problems can occur that affect how the heart or its blood vessels develop. Scientists aren’t completely sure why most heart defects happen. They believe several factors may play a role:
- Genetic Changes: Some heart defects run in families.
- Medications: Certain drugs taken during pregnancy.
- Health Conditions: Some maternal health issues increase risk.
- Environmental Factors: Things like smoking may contribute.
Heart defects fall into several main types:
Changed Connections in the Heart or Blood Vessels
When connections between heart chambers or blood vessels don’t form correctly, blood may flow where it shouldn’t. This can cause oxygen-poor blood to mix with oxygen-rich blood, reducing oxygen levels throughout the body.
The heart and lungs then must work harder to compensate.
Common connection problems include:
| Defect | Description |
|---|---|
| Atrial Septal Defect | A hole between the upper heart chambers (atria) |
| Ventricular Septal Defect | A hole between the lower heart chambers (ventricles) |
| Patent Ductus Arteriosus | A connection between the lung artery and body’s main artery that fails to close after birth |
| Anomalous Pulmonary Venous Connection | Lung blood vessels attach to incorrect areas of the heart |
Heart Valve Problems
Heart valves work like doors between heart chambers and blood vessels. They open and close to keep blood moving in the right direction. Birth defects can cause valves to be too narrow or unable to close properly.
Examples include:
Aortic Stenosis: The aortic valve may have only one or two flaps instead of three, creating a narrow opening. This forces the heart to work harder, eventually causing the heart muscle to thicken.
Pulmonary Stenosis: The pulmonary valve opening is too narrow, slowing blood flow to the lungs.
Ebstein Anomaly: The tricuspid valve (between the right upper and lower chambers) forms abnormally and often leaks.
Complex Heart Defects
Some babies are born with multiple heart problems that can significantly alter blood flow or result in underdeveloped heart chambers:
- Tetralogy of Fallot includes four defects:
- Hole between lower heart chambers
- Thickened muscle in the lower right chamber
- Narrowed path between the heart and lung artery
- Shifted connection of the main artery (aorta)
- Other complex defects include:
Pulmonary Atresia: The pulmonary valve doesn’t form correctly, preventing normal blood flow to the lungs.
Tricuspid Atresia: Solid tissue blocks blood flow between the right upper and lower chambers, causing underdevelopment.
- Transposition of Great Arteries: The two main arteries leaving the heart are reversed. This serious condition comes in two forms:
- Complete Transposition (D-TGA): Usually noticed during pregnancy or soon after birth.
- Levo-Transposition (L-TGA): Less common and symptoms may develop later.
Hypoplastic Left Heart Syndrome: The left side of the heart is severely underdeveloped and cannot pump enough blood to the body.
Risk Factors
Several factors may increase the chance of a baby developing heart defects before birth:
Maternal Infections
- Rubella (German measles) infection during pregnancy can affect heart development
- Pre-pregnancy blood tests can check for immunity
- Vaccination is available for those not immune
Medical Conditions
- Pre-existing diabetes requires careful blood sugar control before and during pregnancy
- Gestational diabetes (developing during pregnancy) typically doesn’t increase heart defect risks
Medications
- Some prescription drugs can harm heart development if taken during pregnancy
- These include lithium (used for bipolar disorder) and isotretinoin (for acne treatment)
- Always discuss all medications with healthcare providers
Lifestyle Factors
- Alcohol consumption during pregnancy raises heart defect risks
- Smoking while pregnant increases the likelihood of heart problems in newborns
- Quitting smoking before or early in pregnancy is strongly recommended
Genetic Factors
- Heart defects often run in families
- Specific gene changes link to certain heart conditions
- Children with Down syndrome frequently have associated heart problems
Complications
Congenital heart defects can lead to several serious health issues. These problems may appear right after birth or develop later in life.
Heart Failure
Babies with severe heart defects may develop heart failure. Look for signs like:
- Fast, gasping breathing
- Poor weight gain
- Difficulty feeding
Heart Lining Infection
The heart’s inner lining and valves can become infected, a condition called endocarditis. This infection may damage heart valves or cause a stroke if not treated.
Regular dental care helps reduce this risk, and doctors may recommend antibiotics before dental procedures.
Abnormal Heart Rhythms
Surgery scars can disrupt normal heart signaling, causing irregular heartbeats. The heart might beat too quickly, too slowly, or with an uneven pattern. Some rhythm problems can lead to stroke or sudden cardiac death without proper treatment.
Developmental Issues
Children with serious heart defects often grow more slowly than their peers. They might:
- Be smaller than other children their age
- Reach developmental milestones later
- Experience delays in walking or talking, especially if the nervous system is affected
Stroke Risk
Blood clots can sometimes pass through heart defects and travel to the brain, causing a stroke. While uncommon, this remains a serious concern.
Psychological Challenges
Many children with heart defects face mental health challenges including:
- Anxiety
- Stress
- Emotional difficulties related to activity restrictions
- Frustration with learning difficulties
Even after successful treatment, complications can appear years later. Regular medical follow-ups remain important throughout life for people born with heart defects.
Preventing Heart Defects at Birth
While doctors don’t know what causes most heart problems that babies are born with, there are ways to lower some risks. Here are key steps for healthier pregnancies:
- Important Prevention Steps:
- Get regular pregnancy checkups.
- Take 400 micrograms of folic acid daily.
- Avoid alcohol and all forms of smoking.
- Get vaccinated against rubella before pregnancy.
- Control diabetes carefully.
- Manage any ongoing health conditions.
Folic acid supplements are especially helpful. They protect against problems in the baby’s brain and spine, and they may also lower the risk of heart defects.
- Health Habits During Pregnancy:
| Avoid These | Choose These |
|---|---|
| Alcohol | Regular doctor visits |
| Cigarettes | Daily vitamins with folic acid |
| Secondhand smoke | Proper diabetes management |
| Strong cleaning products | Safe medicines approved by your doctor |
| Painting fumes | Vaccinations before pregnancy |
If you have ongoing health conditions, talk with your healthcare provider about the safest treatments during pregnancy. Some medicines can cause birth defects, so tell your doctor about everything you take—even over-the-counter products.
For women with a higher risk of having a baby with heart problems, doctors might suggest genetic testing during pregnancy. This testing can provide important information about possible heart defects before birth.
Having someone else handle painting and cleaning with strong chemicals can also protect your developing baby from harmful substances.
