Congenital heart defects occur when the heart or blood vessels near the heart develop abnormally before birth and the baby is born with them. Congenital heart defects affect the normal functions of the heart. Most heart defects either obstruct blood flow to or inside the heart, or cause blood to flow through the heart in an abnormal pattern. The defects range in severity from simple problems to severe malformations that can cause heart failure.
What causes heart defects?
In most cases the cause is not known. A heart defect forms during early pregnancy (between the 6th and 12th week) – very often before a mother realises that she is pregnant. Sometimes the cause can be identified. A mother may have an increased risk of having a baby with a heart defect if during pregnancy she: has a viral infection such as German measles, suffers from diabetes, conditions such as Down’s Syndrome, uses certain medications, abuses alcohol and “street” drugs. A family history also plays a role in congenital heart defects. It is, however, important to emphasise that the abnormality is not the fault of the parents.
What are the common signs and symptoms and what should parents look out for?
Critical congenital heart disease manifests in the first few hours/days of life and often presents with cyanosis or blueness, associated with a blue tongue or blue lips, fast heartbeat, fast breathing, cold hands and feet, and poor pulses to feel. Signs and symptoms in early infancy include poor weight gain, pale or bluish skin colour and especially concerning would be bluish tongues and lips. Fast breathing when sleeping, at rest or feeding is also a concern as is sweating profusely. In older children, signs include tiredness, getting out of breath easily and frequent colds and respiratory illnesses.
Often congenital heart disease is missed or diagnosed too late. Some babies born with a heart defect can appear healthy at first and only develop symptoms later. It is important to ask the sonographer whether your unborn baby’s heart is normal when you have a sonar scan.
Your child should also be tested for CHD before they leave the hospital by a simple test called pulse oximetry screening. Pulse oximetry screening is a simple, non-invasive test that determines the amount of oxygen in a baby’s blood and the baby’s pulse rate. Low levels of oxygen in the blood can be a sign of a CHD or other serious health problems.
Learn more about the different types of congenital heart disease from the Paediatric Cardiac Society of South Africa.