We often think of heart disease as a complication of poor lifestyle choices in adulthood, but did you know that congenital heart defect is the number one birth defect?
Congenital heart disease is defined as a heart defect that occurs as the heart is developing in the mother’s womb. There are 35 well-defined heart defects that can affect newborns. According to the American Heart Association (AHA), 40,000 babies are born with heart defects annually (approximately 1% of babies). Although it is the most common form of birth defect, scientists have not identified why the majority of congenital heart defects occur.
Initially, the heart is a simple tube, but by the third week after conception, it begins to form into a heart with blood vessels and valves. By week eight after conception, the heartbeat is completely formed and audible heartbeats are detected at 12 weeks post conception. Heart defects occur during the first 8 weeks when one crucial step of formation is skipped.
There are several heart defects that can be detected prior to birth using a non-invasive test called “prenatal ultrasound” which is usually done during the fourth month of pregnancy. After birth, a child’s pediatrician will listen to the child’s heartbeat using a stethoscope. He or she is trained to detect “heart-murmurs” or a “whoosh” sound that is an abnormal sound indicating sluggish blood flow or a possible heart defect. If so, a heart ultrasound (echocardiogram) may be used to further evaluate the baby’s heart health.
Another standard procedure parents should ensure the nurse or midwife performs is to check the baby's percent of oxygenation using a painless adaptor on the hand or foot called “pulse oximetry.” If the percent of oxygen is low, this might be an early sign of congenital heart defect and should be further investigated.
Although detection of heart defects has improved in the past decades, a few heart defects may go undetected for weeks and months after birth. Parents should be aware of “clues” for possible heart problems and know how and when to seek help.
Septal defects: The most common form of heart defects is called “septal defects.” These defects involve the muscles of the heart that separate the four chambers. If a “hole” is in the upper chamber of the heart it is called “Atrial Septal Defect” and if it is in the lower chamber of the heart it is called “Ventral Septal Defect.” These defects allow blood to leak through a hole, disrupting the normal flow of blood and oxygenation. Common symptoms of septal defects include rapid development of shortness of breath when running and easy fatigability.
Undetected defects can lead to a shortened lifespan, heart failure, and permanent lung damage.
Transposition of the great arteries: This is among the four most common heart defect in Europe and occurs in 1 in every 3,300 babies born in the US. This defect results when the two largest arteries of the heart (Pulmonary and Aorta) are reversed in their position causing a defect in proper oxygenation and blood flow and, if not surgically corrected, can lead to neonatal death within the first week of life.
Pulmonary atresia: This occurs when the valves between the heart and the lungs under-develop, inhibiting the proper oxygenation of blood and the rest of the body.
Tetralogy of Fallot: This type of heart defect has four characteristics: A hole in the lower chamber of the heart, obstruction of blood flow between heart and lungs, mal-positioned aorta (a main artery in the heart), and enlarged right side of the heart. Early symptoms in newborns are sudden development of deep blue skin, nails, and lips after crying or feeding, or when agitated. All babies born with Tetralogy will need corrective surgery.
Some potential risks factors for fetal heart defects are mothers with diabetes, mothers who contract the Rubella virus during pregnancy or are taking seizure medication, use alcohol, tobacco, cocaine, or have a family history of congenital heart defects. Although congenital heart defects are the most common cause of death, early detection can save a baby’s life. Accompaniment with a trained healthcare provider during pregnancy will usually obtain a very detailed family history, check the mother's blood for diabetes and other infections, offer genetic testing, and perform a fetal ultrasound.
Delivering a healthy baby is every mother’s wish and prayer. Most babies have a perfectly healthy heart. However, detecting heart defects before delivery or shortly after will improve treatment options and the health of the child after birth. As a parent, arm yourself with accurate information regarding your child’s health and possible signs of heart disease and seek immediate help if you suspect any of the above symptoms in your child!
“Dear friend, I pray that you may enjoy good health and that all may go well with you, even as your soul is getting along well,” 3 John 2.
References:
CDC: Screening for Critical Congenital Heart Defects
Mayo Clinic: Tetralogy of Fallot
Stanford Children’s Health: Congenital Heart disease
Unolt M, Putotto C, Silvestri LM, et al. Transposition of Great Arteries: New Insights into the Pathogenesis. Frontiers in Pediatrics. 2013;1:11. doi:10.3389/fped.2013.00011.