Aortic Stenosis in Babies
Medically reviewed by Dr. Michael Okonkwo, MD, FAAP · Board-Certified Neonatologist
Content reviewed against published CDC, AAP, AHA guidelines
Last reviewed:
If your baby has been diagnosed with or you suspect aortic stenosis in babies, here is what the evidence says.
The short answer
Aortic stenosis is a congenital heart defect where the aortic valve (the valve that controls blood flow from the heart to the body) is narrowed, making the left ventricle work harder to pump blood. It can range from mild (requiring only monitoring) to critical (requiring urgent intervention in newborns). Many cases are caused by a bicuspid aortic valve, where the valve has two leaflets instead of the normal three. Mild aortic stenosis may cause only a heart murmur with no symptoms, while severe cases can cause poor feeding, rapid breathing, chest pain, exercise intolerance, or fainting. Treatment options include balloon valvuloplasty, surgical valve repair, or valve replacement.
Key takeaways
- Aortic stenosis is a congenital heart defect where the aortic valve (the valve that controls blood flow from the heart to the body) is narrowed, making the left ventricle work harder to pump blood. It can range from mild (requiring only monitoring) to critical (requiring urgent intervention in newborns). Many cases are caused by a bicuspid aortic valve, where the valve has two leaflets instead of the normal three. Mild aortic stenosis may cause only a heart murmur with no symptoms, while severe cases can cause poor feeding, rapid breathing, chest pain, exercise intolerance, or fainting. Treatment options include balloon valvuloplasty, surgical valve repair, or valve replacement.
- Usually normal when: Your baby has mild aortic stenosis with a low gradient and the cardiologist recommends only periodic monitoring
- Call your doctor if: Your newborn has rapid breathing, poor feeding, pallor, weak pulses, or grayish skin -- these may indicate critical aortic stenosis and require immediate emergency care
- Varies by age — see the age-by-age breakdown below
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What Parents Should Know
According to CDC, AAP, AHA guidelines, aortic stenosis is a congenital heart defect where the aortic valve (the valve that controls blood flow from the heart to the body) is narrowed, making the left ventricle work harder to pump blood. It can range from mild (requiring only monitoring) to critical (requiring urgent intervention in newborns). Many cases are caused by a bicuspid aortic valve, where the valve has two leaflets instead of the normal three. Mild aortic stenosis may cause only a heart murmur with no symptoms, while severe cases can cause poor feeding, rapid breathing, chest pain, exercise intolerance, or fainting. Treatment options include balloon valvuloplasty, surgical valve repair, or valve replacement. At 0-3 months, critical aortic stenosis in newborns is a medical emergency. As the ductus arteriosus closes, the baby may develop heart failure with rapid breathing, poor feeding, pallor, weak pulses, and grayish skin. These babies require prostaglandin infusion to keep the ductus open and urgent balloon valvuloplasty or surgery. Less severe stenosis may present as a heart murmur detected at the newborn exam. A systolic ejection murmur heard best at the upper right sternal border with radiation to the neck is characteristic. It is generally considered normal when your baby has mild aortic stenosis with a low gradient and the cardiologist recommends only periodic monitoring. However, you should contact your pediatrician promptly if your newborn has rapid breathing, poor feeding, pallor, weak pulses, or grayish skin -- these may indicate critical aortic stenosis and require immediate emergency care.
Normal vs. Concerning
When to Seek Immediate Care
- Your newborn has rapid breathing, poor feeding, pallor, weak pulses, or grayish skin -- these may indicate critical aortic stenosis and require immediate emergency care
- Your child with known aortic stenosis faints or loses consciousness during exercise or physical activity -- call 911
- Your child complains of severe chest pain or becomes very short of breath during physical activity -- seek emergency evaluation
By Age
What to expect by age
0-3 months
Critical aortic stenosis in newborns is a medical emergency. As the ductus arteriosus closes, the baby may develop heart failure with rapid breathing, poor feeding, pallor, weak pulses, and grayish skin. These babies require prostaglandin infusion to keep the ductus open and urgent balloon valvuloplasty or surgery. Less severe stenosis may present as a heart murmur detected at the newborn exam. A systolic ejection murmur heard best at the upper right sternal border with radiation to the neck is characteristic.
3-12 months
Infants with mild to moderate aortic stenosis usually have no symptoms and grow normally. The murmur may become more prominent during illness or fever. Echocardiography is used to measure the pressure gradient across the valve and assess left ventricular function. Infants who had balloon valvuloplasty in the newborn period are monitored for residual stenosis or development of aortic valve leakage (regurgitation). Regular cardiology follow-up is important because stenosis can worsen as the child grows.
1-3 years
Toddlers with mild aortic stenosis typically have no activity restrictions and lead normal lives. Moderate stenosis may cause subtle exercise intolerance. The cardiologist monitors the gradient across the valve with periodic echocardiograms. If the gradient increases significantly (typically above 50 mmHg mean gradient or 70 mmHg peak gradient), intervention is considered. Toddlers with bicuspid aortic valve are also monitored for aortic root dilation.
3+ years
Older children with moderate to severe aortic stenosis may experience chest pain, dizziness, or fainting during exercise. These symptoms indicate that intervention is needed. Children with significant aortic stenosis typically have activity restrictions, particularly avoiding competitive or strenuous sports. Treatment may include balloon valvuloplasty, surgical valve repair (Ross procedure), or valve replacement. The Ross procedure uses the patient's own pulmonary valve to replace the aortic valve and is preferred in growing children.
What to Tell Your Pediatrician
- Describe when you first noticed aortic stenosis in babies and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if your baby has a heart murmur that has not been evaluated with echocardiography.
- Mention if your child with known aortic stenosis seems to tire more quickly during physical activity or complains of chest discomfort.
- Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
- Bring a list of any questions or observations you want to discuss at the appointment.
What Should You Do?
When to take action
- Your baby has mild aortic stenosis with a low gradient and the cardiologist recommends only periodic monitoring
- A heart murmur was evaluated and echocardiogram showed a bicuspid aortic valve with no significant narrowing
- Your child with mild aortic stenosis is active, growing well, and has no symptoms
- Your child had successful intervention for aortic stenosis and follow-up shows good valve function
- Your baby has a heart murmur that has not been evaluated with echocardiography
- Your child with known aortic stenosis seems to tire more quickly during physical activity or complains of chest discomfort
- Your child with aortic stenosis has not had a cardiology follow-up in over a year
- You have a family history of bicuspid aortic valve or aortic stenosis
- Your newborn has rapid breathing, poor feeding, pallor, weak pulses, or grayish skin -- these may indicate critical aortic stenosis and require immediate emergency care
- Your child with known aortic stenosis faints or loses consciousness during exercise or physical activity -- call 911
- Your child complains of severe chest pain or becomes very short of breath during physical activity -- seek emergency evaluation
What You Can Do at Home
- Keep track of when you notice aortic stenosis in babies — noting the time of day, duration, and any triggers can help your pediatrician.
- Remember that your baby has mild aortic stenosis with a low gradient and the cardiologist recommends only periodic monitoring — this is generally within the range of normal.
- At 0-3 months, focus on observation rather than intervention unless your pediatrician advises otherwise.
- Follow any care instructions from your pediatrician. Keep a written log of symptoms to bring to appointments.
- While monitoring at home, seek immediate care if your newborn has rapid breathing, poor feeding, pallor, weak pulses, or grayish skin -- these may indicate critical aortic stenosis and require immediate emergency care.
Related Conditions
Congenital Heart Defect Signs in Babies
Congenital heart defects (CHDs) are the most common type of birth defect, affecting about 1 in 100 babies. They range from small holes in the heart that may close on their own to complex defects requiring multiple surgeries. Early detection through pulse oximetry screening and recognizing key signs — such as blue skin, rapid breathing, poor feeding, and failure to gain weight — is critical. Advances in surgery have dramatically improved survival and quality of life.
Baby Heart Murmur - Innocent vs Concerning
Heart murmurs are very common in children - up to 75% of children will have an audible murmur at some point. The vast majority are "innocent" or "functional" murmurs, meaning there is no structural heart problem. These murmurs are simply the sound of blood flowing normally through the heart and are more audible during fever, illness, or excitement. A smaller number of murmurs indicate a structural heart difference that may need monitoring or treatment. Your pediatrician can usually distinguish between the two and will refer for an echocardiogram if there is any concern.
Coarctation of the Aorta in Babies
Coarctation of the aorta is a narrowing of the body's main artery (the aorta) that reduces blood flow to the lower body. It accounts for about 5-8% of all congenital heart defects. It can present in newborns as a critical emergency or be diagnosed later in childhood through high blood pressure or a heart murmur. Surgical repair or catheter-based intervention is very effective, with most children leading normal lives afterward.
My Baby Turns Blue (Cyanosis)
Blue or purple discoloration limited to a baby's hands and feet (acrocyanosis) is very common in newborns and usually harmless, caused by immature circulation. However, blue coloring of the lips, tongue, face, or trunk (central cyanosis) is always a medical emergency that requires immediate evaluation, as it may indicate a heart or lung problem.
Related Resources
Frequently asked questions
Is aortic stenosis in babies normal?
When should I call the doctor about aortic stenosis in babies?
When is aortic stenosis in babies normal?
What causes aortic stenosis in babies?
What should I mention to my pediatrician about aortic stenosis in babies?
Is aortic stenosis in babies normal at 0-3 months?
Is aortic stenosis in babies normal at 3-12 months?
Should I go to the ER for aortic stenosis in babies?
Does aortic stenosis in babies go away on its own?
References
Doctor Visit Checklist
Bring this checklist to your next pediatrician visit to discuss Aortic Stenosis in Babies.
Things to mention
- Describe when you first noticed aortic stenosis in babies and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if your baby has a heart murmur that has not been evaluated with echocardiography.
- Mention if your child with known aortic stenosis seems to tire more quickly during physical activity or complains of chest discomfort.
- Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
- Bring a list of any questions or observations you want to discuss at the appointment.
Observations to share
- Your baby has a heart murmur that has not been evaluated with echocardiography
- Your child with known aortic stenosis seems to tire more quickly during physical activity or complains of chest discomfort
- Your child with aortic stenosis has not had a cardiology follow-up in over a year
Urgent signs to report immediately
- Your newborn has rapid breathing, poor feeding, pallor, weak pulses, or grayish skin -- these may indicate critical aortic stenosis and require immediate emergency care
- Your child with known aortic stenosis faints or loses consciousness during exercise or physical activity -- call 911
- Your child complains of severe chest pain or becomes very short of breath during physical activity -- seek emergency evaluation
My notes
From ismybabyalright.com — free, evidence-based baby health guides
All content follows our editorial policy and is reviewed against published clinical guidelines.
2,705 evidence-based guides6 authoritative medical sources5 medical advisory board members
Related Resources
Bottom line
Most cases of aortic stenosis in babies are normal. Talk to your pediatrician if your newborn has rapid breathing, poor feeding, pallor, weak pulses, or grayish skin -- these may indicate critical aortic stenosis and require immediate emergency care.
Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.
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Related Medical Concerns
Congenital Heart Defect Signs in Babies
Congenital heart defects (CHDs) are the most common type of birth defect, affecting about 1 in 100 babies. They range from small holes in the heart that may close on their own to complex defects requiring multiple surgeries. Early detection through pulse oximetry screening and recognizing key signs — such as blue skin, rapid breathing, poor feeding, and failure to gain weight — is critical. Advances in surgery have dramatically improved survival and quality of life.
Baby Heart Murmur - Innocent vs Concerning
Heart murmurs are very common in children - up to 75% of children will have an audible murmur at some point. The vast majority are "innocent" or "functional" murmurs, meaning there is no structural heart problem. These murmurs are simply the sound of blood flowing normally through the heart and are more audible during fever, illness, or excitement. A smaller number of murmurs indicate a structural heart difference that may need monitoring or treatment. Your pediatrician can usually distinguish between the two and will refer for an echocardiogram if there is any concern.
Coarctation of the Aorta in Babies
Coarctation of the aorta is a narrowing of the body's main artery (the aorta) that reduces blood flow to the lower body. It accounts for about 5-8% of all congenital heart defects. It can present in newborns as a critical emergency or be diagnosed later in childhood through high blood pressure or a heart murmur. Surgical repair or catheter-based intervention is very effective, with most children leading normal lives afterward.
My Baby Turns Blue (Cyanosis)
Blue or purple discoloration limited to a baby's hands and feet (acrocyanosis) is very common in newborns and usually harmless, caused by immature circulation. However, blue coloring of the lips, tongue, face, or trunk (central cyanosis) is always a medical emergency that requires immediate evaluation, as it may indicate a heart or lung problem.
My Baby's Head Shape Looks Abnormal
Many babies develop temporary head shape irregularities that are completely normal. A cone-shaped head from vaginal delivery reshapes within days. Mild positional flattening (plagiocephaly) from sleeping on the back is very common and usually improves with repositioning and tummy time. However, head shape changes involving ridges, a persistently bulging fontanelle, or rapid head growth changes should be evaluated to rule out craniosynostosis.
Achondroplasia (Dwarfism) in Babies
Achondroplasia is the most common form of short-limbed dwarfism, affecting about 1 in 15,000 to 40,000 births. It is caused by a mutation in the FGFR3 gene and is usually apparent at birth with characteristic features including short limbs, a larger head, and a prominent forehead. Intelligence is normal. With monitoring for specific complications and supportive care, children with achondroplasia lead full, active, and independent lives.