A baby’s heartbeat is the soundtrack of their life, always keeping time as they grow each day. But sometimes, with no fault to their mothers or themselves, babies’ hearts don’t grow quite right in the womb, and they need special care and attention as they grow.
What Are Congenital Heart Defects?
Congenital heart disease is the term used to describe the variety of heart defects that a baby could be born with and carry with them into adulthood. A congenital heart defect is any heart abnormality that a baby develops in the womb.
By the eighth week of pregnancy, a baby's heart is fully formed. Congenital heart defects happen during these first eight weeks. The heart develops in a series of steps, and problems can occur when one of these steps doesn’t happen at the right time. It could mean instead of a dividing wall in the heart, there’s a hole, or where two blood vessels should be, there’s only one.
Congenital heart defects are the most common birth defect and, most importantly, they’re treatable with the compassionate care offered every day at AdventHealth.
What Causes Congenital Heart Disease?
Unfortunately, it’s not yet clear what causes congenital heart defects. New mothers might be nervous that it’s the result of something they did or didn’t do during pregnancy, but in most cases, there’s no identifiable cause.
Health experts think some potential causes of congenital heart defects could include:
- A disease the mother faced during pregnancy
- Genetics, because some heart problems run in families
- Medication use during pregnancy, like taking anti-seizure medicines or the acne medicine isotretinoin
Do Congenital Heart Defects Heal on Their Own?
Congenital heart problems can be simple or complex, and they might heal on their own or, in many cases, need treatment. A baby’s doctor may monitor the heart’s growth and prescribe medicines as needed. Other babies may need surgery, sometimes as soon as in the first few hours after birth.
In some cases, a baby may grow out of some of the simpler heart problems, such as patent ductus arteriosus or an atrial septal defect. These defects may simply close up on their own as the baby grows. Other babies might have a combination of heart problems and require several operations throughout their lives.
Types of Congenital Heart Defects
Doctors separate congenital heart defects into three categories based on how they affect blood flow. Depending on the type, congenital heart defects can cause:
- Too much blood to pass through the lungs
- Too little blood to pass through the lungs
- Too little blood to travel to the body
There are specific congenital heart defects in each of these three categories.
1. Defects That Cause Too Much Blood to Pass Through the Lungs
These heart problems allow oxygen-rich blood to recirculate through the lungs, when it should be traveling to the body, instead. These issues cause increased pressure and stress in the lungs.
Four defects cause too much blood to pass through the lungs: atrial septal defects, atrioventricular canal, patent ductus arteriosus and ventricular septal defect.
Atrial Septal Defect
In this condition, there’s a hole between the two upper chambers of the heart (the right and left atria). The hole causes abnormal blood flow through the heart. Some babies who have an atrial septal defect may have no symptoms and appear healthy. However, if the hole is large, permitting a large amount of blood to pass to the right side, symptoms may be noticeable.
Atrioventricular canal is a heart problem that means that there are several abnormal structures inside the heart. These include atrial septal defect, ventricular septal defect and mitral or tricuspid valves that formed improperly.
Patent Ductus Arteriosus
This issue happens when the normal closure of the ductus arteriosus — a blood vessel in the heart that’s present in all unborn babies — does not occur. Extra blood travels from the aorta into the lungs and may lead to flooding of the lungs, rapid breathing and poor weight gain. It’s often seen in premature infants.
Ventricular Septal Defect
In this condition, there’s a hole in the ventricular septum, which is a dividing wall between the two lower chambers of the heart. Because of this hole, blood from the left ventricle flows back into the right ventricle. Extra blood is then pumped into the lungs by the right ventricle, which can create congestion in the lungs.
2. Defects That Cause Too Little Blood to Pass Through the Lungs
These defects allow oxygen-poor blood to travel through the body. The body does not get enough oxygen with these heart problems, and the baby may look blue, or cyanotic.
Six defects cause too little blood to pass through the lungs: double outlet right ventricle (DORV), pulmonary atresia, tetralogy of Fallot, transposition of the great arteries, tricuspid atresia and truncus arteriosus.
Double Outlet Right Ventricle (DORV)
This condition is a complex and rare defect in which both the aorta and the pulmonary artery (two main arteries in the heart) are connected to the right ventricle. Normally, the aorta connects with the left ventricle instead, and the pulmonary artery connects with right ventricle. Oxygen-poor blood travels through the body because of this condition.
With pulmonary atresia, the pulmonary valve or artery is underdeveloped. Normally, the pulmonary valve is found between the right ventricle and the pulmonary artery. Its three leaflets function like one-way doors, allowing blood to flow forward into the pulmonary artery, but not backward into the right ventricle.
With pulmonary atresia, problems with how valves form prevent the leaflets from opening. This means that blood can’t flow forward from the right ventricle to the lungs.
Tetralogy of Fallot
This condition is characterized by four specific defects:
- A ventricular septal defect
- A narrowing (stenosis) at the pulmonary valve
- An "overriding" aorta, which lies directly over the ventricular septal defect
- Thickening or enlargement of the right ventricle
Tetralogy of Fallot can cause babies to have a bluish color to their skin, called cyanosis, from receiving too little oxygen.
Transposition of the Great Arteries
With this defect, the positions of the pulmonary artery and the aorta are reversed, which causes several issues, like:
- Most of the oxygen-poor blood returning to the heart from the body is pumped back out without first going to the lungs
- Most of the oxygen-rich blood returning from the lungs goes back to the lungs again
In this condition, the tricuspid valve does not form, so no blood flows from the right atrium to the right ventricle. Tricuspid atresia is characterized by:
- A bluish color of the skin and mucous membranes (cyanosis)
- A small right ventricle
- Poor blood flow to the lungs
Babies may need surgery to increase the blood flow to the lungs and establish separate circulations.
As babies grow in the womb, the aorta and pulmonary artery start as a single blood vessel, and then the vessel divides into two separate arteries. Truncus arteriosus occurs when the single great vessel doesn’t separate completely.
3. Defects That Cause Too Little Blood to Travel to the Body
These issues happen because of underdeveloped chambers of the heart or blockages in blood vessels. Underdeveloped heart chambers or blocked blood vessels prevent the right amount of blood from traveling to the baby’s body.
Three problems that cause too little blood to travel to the body include coarctation of the aorta, aortic stenosis and hypoplastic left heart syndrome.
Coarctation of the Aorta
In this condition, the aorta is too narrow, and it blocks blood flow to the lower parts of the body and increases blood pressure. Usually, there are no symptoms of coarctation of the aorta at birth, but they can develop as early as the first week of life. If severe symptoms of high blood pressure and congestive heart failure develop, a baby may need surgery.
In aortic stenosis, the aortic valve between the left ventricle and the aorta did not form properly and is narrowed. This makes it difficult for the heart to pump blood to the body. A normal valve has three leaflets or cusps, but a stenotic valve may have only one or two cusps. Although aortic stenosis may not cause symptoms, it may worsen over time, and surgery might be necessary.
Hypoplastic Left Heart Syndrome
This syndrome is a combination of several abnormalities of the heart and the great blood vessels. In this condition, most of the structures on the left side of the heart don’t develop quite right. The left ventricle may not be able to pump enough blood to the body, so this condition requires immediate treatment.
Doctors Dedicated to Healing Congenital Heart Disease
Babies who have any of these congenital heart problems can receive the treatment they need from specialists called pediatric cardiologists. These doctors diagnose heart defects and help children stay healthy before and after surgery for congenital heart disease.
But it’s not just babies who live with congenital heart disease. Many American adults have this condition, too. It’s important for anyone born with congenital heart disease transition to the appropriate cardiac care, depending on the type of disease they have and its severity. At any age, managing congenital heart disease is possible with the right care.
Whole-Hearted Care You Can Count On
For parents, learning that their baby has a congenital heart defect is challenging in more ways than one. That’s why at AdventHealth, we know that uncommon compassion is just as important as expert care for congenital heart disease. From before a diagnosis to well beyond, we’re here for you and your family. Learn more about heart and vascular care at AdventHealth.