Congenital Heart Defects
Congenital heart defects are structural problems with the heart present at birth that occur when a fetus's heart does not develop normally during pregnancy.
Overview
Congenital heart defects (CHDs) are the most common type of birth defect. These conditions can change the way the heart pumps blood, potentially causing blood to flow too slowly, move in the wrong direction, or become completely blocked.
There are many types of congenital heart defects, which can affect one or more parts of the heart. The most common types include:
- Septal defects ("hole in the heart") — openings in the wall between the left and right sides of the heart.
- Heart valve defects — problems with the valves that control the flow of blood through the heart.
- Defects in the large blood vessels that carry blood in and out of the heart.
These defects range from mild issues that require no treatment to life-threatening conditions known as critical congenital heart disease. While babies with critical defects usually require surgery within their first year, milder defects may not present symptoms until childhood or adulthood.
Causes & Risk Factors
While researchers often do not know the exact cause of CHDs, they are known to be linked to genetic changes that may be inherited or occur during pregnancy. Factors that increase the likelihood of a baby having a congenital heart defect include:
Health Before and During Pregnancy
- Diabetes: Having diabetes before or during the first three months of pregnancy. Controlling blood glucose levels can lower the baby's risk.
- Phenylketonuria (PKU): A rare inherited disorder affecting protein metabolism. A low-protein diet before pregnancy can lower the baby's risk.
- Rubella: Having German measles during pregnancy.
Contact with Substances
- Smoking or exposure to secondhand smoke.
- Certain medicines, such as angiotensin-converting (ACE) inhibitors for high blood pressure and retinoic acids for acne.
Family History
- While most cases do not run in families, the risk increases if a parent or a sibling has a congenital heart defect.
Symptoms
Congenital heart defects do not cause pain. Symptoms vary based on the type and severity of the defect and may include:
- Cyanosis: A bluish color to the skin, lips, and fingernails due to low oxygen in the blood.
- Fatigue: Unusual sleepiness or extreme tiredness during feedings.
- Poor blood flow.
- Fast or difficult breathing.
- Heart murmur: An unusual sound between heartbeats.
Other Potential Complications
Children with CHDs may be smaller than their peers and may experience delays in mental, emotional, or behavioral growth, such as speech and language problems or Attention deficit hyperactivity disorder (ADHD). Adults and children may also develop:
- Endocarditis: An infection of the lining of the heart and valves.
- Arrhythmia: A problem with the rate or rhythm of the heartbeat.
- Heart failure: When the heart cannot pump enough blood to the body.
- Pulmonary hypertension: High blood pressure in the lungs.
- Kidney and liver disease.
Diagnosis
- Prenatal: Providers may use a fetal echocardiogram between weeks 18 and 22 of pregnancy to view the fetus's heart.
- Newborn screening: A pulse oximeter is used in the first few days of life to measure blood oxygen levels.
- Diagnostic tools: For babies, children, and adults, providers may use physical exams, heart tests, or genetic testing.
Treatment & Management
Treatment depends on the specific defect and its severity:
- Cardiac catheterization: A thin tube is guided into the heart to repair simple defects.
- Heart surgery: Used to repair or replace valves, fix blood vessels, place heart-pumping devices, or perform a heart transplant.
- Medicine: Often used for patent ductus arteriosus.
All individuals with CHDs require lifelong follow-up care from a cardiologist, as some may require multiple surgeries or ongoing medication.