What Causes It?
Genetic factors - Certain genetic and chromosomal abnormalities, such as Down syndrome, Turner syndrome, and 22q11.2 deletion syndrome, are strongly associated with heart defects.
Family history - Having a parent or sibling with a congenital heart defect increases the risk.
Environmental factors during pregnancy - Exposure to certain substances or conditions during critical periods of heart development.
Maternal medications - Some medications taken during pregnancy, such as certain anti-seizure drugs, ACE inhibitors, retinoic acid, or lithium.
Maternal infections - Certain infections during pregnancy, particularly rubella (German measles).
Maternal health conditions - Poorly controlled diabetes, lupus, or phenylketonuria (PKU) during pregnancy.
Alcohol consumption - Drinking alcohol during pregnancy can lead to fetal alcohol syndrome, which may include heart defects.
Smoking - Maternal smoking increases the risk of certain heart defects.
Advanced maternal age - Being over 35 years old when pregnant may slightly increase risk.
Maternal obesity - Being significantly overweight during pregnancy may increase risk.
Multiple factors - Most congenital heart defects result from a complex interaction between genetic predisposition and environmental factors.
In many cases, the exact cause remains unknown despite extensive investigation.
Signs & Symptoms
Symptoms vary widely depending on the type and severity of the defect. Some may cause no symptoms, while others can be life-threatening.
In newborns and infants:
Blue-tinged lips, skin, and nails (cyanosis) due to low oxygen levels in the blood.
Rapid breathing or difficulty breathing, especially during feeding.
Poor feeding and poor weight gain (failure to thrive).
Excessive sweating, particularly during feeding.
Heart murmur (abnormal heart sound detected by a doctor).
In older children:
Easily tiring or becoming short of breath during physical activity.
Fainting during physical activity.
Swelling in the legs, abdomen, or around the eyes.
Abnormal heart rhythm or palpitations.
Dizziness or lightheadedness.
Delayed growth and development compared to peers.
Signs of specific complex defects may include:
Tet spells - Sudden, deep blue skin discoloration with irritability in infants with tetralogy of Fallot.
Clubbing of fingers and toes - Enlargement of the fingertips due to chronic low oxygen levels.
In severe cases, heart failure symptoms may develop, including:
Persistent cough or wheezing.
Swelling in the body tissues, especially in the legs, ankles, and feet.
Abnormal heart rhythms.
Poor exercise tolerance.