Centers for Disease Control and Prevention says Screening for Critical Congenital Heart Defects
Congenital heart defects (CHDs) account for 24% of infant deaths due to birth defects.1 In the United States, about 4,800 (or 11.6 per 10,000) babies born every year have one of seven critical congenital heart defects (CCHDs, which also are known collectively in some instances as critical congenital heart disease). These seven CCHDs are hypoplastic left heart syndrome, pulmonary atresia (with intact septum), tetralogy of Fallot, total anomalous pulmonary venous return, transposition of the great arteries, tricuspid atresia, and truncus arteriosus. Babies with one of these CCHDs are at significant risk of disability or death if their CCHD is not diagnosed soon after birth. These seven CCHDs among some babies potentially can be detected using pulse oximetry screening, which is a test to determine the amount of oxygen in the blood and pulse rate. Other heart defects can be just as severe as these seven CCHDs and also require treatment soon after birth. However, pulse oximetry screening may not detect these heart defects as consistently as the seven disorders listed as CCHDs.
The Importance of Screening for Critical Congenital Heart Defects
Some babies born with a heart defect can appear healthy at first and can be sent home with their families before their heart defect is detected. It is estimated that at least 280 infants with an unrecognized CCHD are discharged each year from newborn nurseries in the United States. These babies are at risk of having serious complications within the first few days or weeks of life and often require emergency care.
Learn More About Congenital Heart Defects
Newborn screening using pulse oximetry can identify some infants with a CCHD before they show signs of a CCHD. Once identified, babies with a CCHD can be seen by cardiologists and can receive specialized care and treatment that can prevent disability and death early in life. Treatment can include medications and surgery.
When and How Babies Are Screened
Pulse oximetry is a simple bedside test to determine 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 CCHD. The test is done using a machine called a pulse oximeter, with sensors placed on the baby’s skin. The test is painless and takes only a few minutes. Screening is done when a baby is 24 to 48 hours of age, or as late as possible if the baby is to be discharged from the hospital before he or she is 24 hours of age.
Pulse oximetry screening does not replace a complete history and physical examination, which sometimes can detect a CCHD before the development of low levels of oxygen in the blood. Pulse oximetry screening, therefore, should be used along with the physical examination.
CCHD Screening Results
If the results are “negative” (“pass” or in-range result), it means that the baby’s test results did not show signs of a CCHD. This type of screening test does not detect all CCHDs, so it is possible for a baby with a negative screening result to still have a CCHD or other congenital heart defect. If the results are “positive” (“fail” or out-of-range result), it means that the baby’s test results showed low levels of oxygen in the blood, which can be a sign of a CCHD. This does not always mean that the baby has a CCHD. It just means that more testing is needed.
The baby’s doctor might recommend that the infant get screened again or have more specific tests, like an echocardiogram (an ultrasound picture of the heart), to diagnose a CCHD. Babies who are found to have a CCHD also might be evaluated by a clinical geneticist. This could help identify genetic syndromes associated with CCHDs and inform families about future risks.