Critical Congenital Heart Defects in the United States
The Centers for Disease Control and Prevention and the National Birth Defects Prevention Network (NBDPN)External recently published two papers titled, “Selected Birth Defects Data from Population-based Birth Defects Surveillance Programs in the United States, 2005-2009: Featuring Critical Congenital Heart Defects Targeted for Pulse Oximetry ScreeningExternal” and “Newborn Screening for Critical Congenital Heart Disease: Essential Public Health Roles for Birth Defects Monitoring ProgramsExternal” in Birth Defects Research Part A: Clinical and Molecular Teratology. See below for a summary of these articles.
Main Finding from These Studies:
These papers describe new U.S. data for 7 types of critical congenital heart defects (CCHDs) and describe ways that birth defects tracking programs can help with newborn screening for CCHDs.
About These Studies:
What are critical congenital heart defects?
Congenital heart defects (CHD) occur in about 1 in 110 births in the U.S. About 25% of CHDs are considered critical congenital heart defects (CCHDs, also known as critical congenital heart disease). Children with CCHDs need surgery or other procedures within the first year of life. They are at risk for death or disability if their heart defect is not detected soon after birth.
What is newborn screening?
Soon after birth, all babies born in the U.S. are checked for certain medical conditions. This is called newborn screening. All babies are screened, even if they look healthy, because some medical conditions cannot be seen by just looking at the baby. Finding these conditions soon after birth can help prevent some serious problems, such as brain damage, organ damage, and even death. The Recommended Uniform Screening Panel is a list of conditions for which all newborns should be screened, as recommended by the U.S. Secretary of Health and Human Services (HHS).
What is newborn screening for critical congenital heart defects?
In 2011, the Secretary of HHS recommended that critical congenital heart disease be added to the U.S. Recommended Uniform Screening Panel for newborns. Currently, newborn screening for CCHDs involves a simple bedside test to determine the amount of oxygen in a baby’s blood. Low levels of oxygen in the blood can be a sign of a CCHD. Seven CCHDs are the main targets for screening: common truncus, d-transposition of the great arteries, tetralogy of Fallot, pulmonary valve atresia, tricuspid valve atresia, hypoplastic left heart syndrome, and total anomalous pulmonary venous return. Other CCHDs may also be detected through screening, but not as consistently. Critical CHD screening has begun in most states, where laws requiring this screening have been proposed or passed.
What are state birth defects tracking programs?
Birth defects tracking programs, also called birth defects surveillance programs or birth defects monitoring programs, are important for finding and collecting information about birth defects. Information from birth defects tracking systems is used by public-health officials, policy-makers, and scientists for the following activities:
- To understand if the number of birth defects is increasing or decreasing over time.
- To investigate possible causes of and risk factors for birth defects.
- To educate the public about birth defects and how to prevent them.
- To plan and evaluate activities aimed at preventing birth defects.
- To refer babies and families affected by birth defects to appropriate services.
- To help policymakers assign resources and services for affected babies and their families.
In a survey of the 50 states and Washington, D.C., 43 responded that they have a birth defects tracking program.
How common are critical congenital heart defects?
The paper titled, “Selected Birth Defects Data from Population-based Birth Defects Surveillance Programs in the United States, 2005-2009: Featuring Critical Congenital Heart Defects Targeted for Pulse Oximetry Screening” included data from 34 birth defects tracking programs on the number of children born with each of the CCHD main screening targets from 2005 to 2009. This information was used to determine the prevalence of each CCHD per 10,000 live births. Prevalence at birth is the fraction of babies with a CCHD out of the total number of live births.
The prevalence of specific CCHDs was different in different states. This table shows the lowest and highest prevalence of each CCHD from all the states that provided information:
|CCHD||Lowest prevalence per 10,000 live births||Highest prevalence per 10,000 live births|
|Hypoplastic left heart syndrome||0.7||4.8|
|Pulmonary valve atresia and stenosis||0.3||24.6|
|Pulmonary valve atresia||0.2||2.6|
|Tetralogy of Fallot||0.9||6.2|
|Total anomalous pulmonary venous return||0.1||2.0|
|dextro-transposition of the great arteries||0.5||4.1|
|Tricuspid valve atresia and stenosis||0||2.2|
|Tricuspid valve atresia||0.1||1.7|
Why does the prevalence of CCHDs differ among states?
It is important to remember that there are differences in the way programs collect and report birth defects data. This could explain the difference seen across states.
- Some programs could only provide data for some years.
- Some programs were not able to provide data on some CCHDs because they did not track the CCHD or they could not tell the more specific CCHD apart from the broader category.
- Pregnancy termination rates for CCHDs found during pregnancy vary among states.
- State programs use different methods, called active and passive systems, to find children with CCHDs.
- Those with active systems send staff to hospitals and other care facilities to collect information on children with CCHDs. This type of review can be time and resource intensive, but often identifies more children with birth defects.
- Programs with passive systems rely on hospitals and other care facilities to send them information on children with CCHDs.
How can state birth defects tracking programs help with newborn screening for CCHDs?
Birth defects tracking programs can play a key role in starting and evaluating CCHD newborn screening. For hospitals and states that are starting CCHD screening, birth defects tracking programs could help organize screening, communication, and follow-up activities. They could assist with educating parents and training health care workers about CCHD screening.
For hospitals and states already screening for CCHDs, birth defects tracking programs could help evaluate:
- Health outcomes after newborn screening among children with a CCHD
- Number of children with a CCHD who were not screened or had a normal screening result (false negative), why they were missed, and how this information could be used to improve screening
- Usefulness for screening for conditions other than the main screening targets
- Differences in how well children with CCHDs are detected in different areas
- How screening works at higher altitudes, which require different cutoffs/methods
- Effects of rural vs. urban living, race/ethnicity, maternal age, or place of delivery on rates of screening and outcomes
- Number of CCHDs found during pregnancy or after birth but before newborn screening, because these babies’ CCHDs will already be known and thus these babies will not benefit from screening
- Costs and service use (for example, location/type of birthing center, transfers, transports, hospitalizations, and rehabilitation services).
To help with these evaluations, birth defects tracking programs would need:
- To be in place wherever screening occurs and to work together with newborn screening programs
- Experts to review medical records, echocardiogram results, and other data sources and to identify the CCHD in the child
- Prompt feedback to help improve CCHD screening
- Long-term follow-up activities to track outcomes in children after their CCHD is detected through newborn screening
- Outcomes include death, disability, use of health services, and costs
- List of what information must be collected and methods for assessing the quality of the data collected
- Agreements that allow data to be sent from one state to another, for example, for places where births or health services provided after birth often occur in a nearby state
- Common standards for defining CCHDs and entering these CCHDs into databases to allow comparisons between states and over time
- Would allow data from different states to be combined, in order to improve evaluations for rarer defects or some races/ethnicities
References for Key Findings Feature
Mai CT, Riehle-Colarusso T, O’Halloran A, Cragan JD, et al. 2012. Selected Birth Defects Data from Population-based Birth Defects Surveillance Programs in the United States, 2005-2009: Featuring Critical Congenital Heart Defects Targeted for Pulse Oximetry Screening. Birth Defects Research Part A: Clinical and Molecular Teratology. 94: 970-983.
Olney RS, Botto LD. 2012. Newborn Screening for Critical Congenital Heart Disease: Essential Public Health Roles for Birth Defects Monitoring Programs. Birth Defects Research Part A: Clinical and Molecular Teratology. 94: 965-969.