Aortic stenosis in children and infants causes complications and treatment

Aortic coarctation in infants and children is one of the most common congenital heart problems, affecting the blood flow from the heart to the rest of the body. If diagnosis or treatment is delayed, it can lead to serious complications such as high blood pressure and heart failure. In this article from Dalily Medical, we’ll cover the causes of aortic coarctation, its types, diagnostic methods, and the latest surgical and non-surgical treatment options, to help you understand your child’s condition and ensure their health and normal growth.

What is Aortic Coarctation in Children?

Aortic coarctation in children is a congenital heart defect present from birth, where the aorta – the body’s largest artery – is narrower than normal. The aorta is responsible for carrying oxygen-rich blood from the heart to the rest of the body. When it’s narrowed, the heart struggles to pump blood through the constricted area, which can lead to serious health problems if left untreated.

Structure and Function of the Aorta
The aorta resembles a candy cane in shape:

Ascending aorta: The section that moves upward to supply blood to the head and arms.
Aortic arch: The curved part from which smaller arteries branch off to supply the head and arms.
Descending aorta: The part that continues downward to deliver blood to the rest of the body.

Narrowing can occur in any part of the aorta, affecting the amount of blood that reaches different organs.

How Common is Aortic Coarctation in Children?

About 4 in every 10,000 children are born with aortic coarctation, which equals roughly 2,200 children per year.
Among children with any type of congenital heart disease, approximately 7 out of 100 have aortic coarctation.

Causes of Aortic Coarctation in Children
Aortic coarctation is a congenital condition, meaning children are born with it. It causes narrowing of the aorta, which reduces blood flow from the heart to the rest of the body. Main causes include:

1️⃣ Congenital Defects in the Aorta
Most cases are congenital. The aortic valve may be malformed:

Tricuspid valve malformation (abnormal three-leaflet valve)
Bicuspid aortic valve (two leaflets instead of three)

This narrowing reduces blood flow from the heart and increases pressure on the left ventricle.

2️⃣ Genetic and Hereditary Causes
Some cases are associated with genetic syndromes such as Williams syndrome or other congenital heart abnormalities.
A family history of heart valve disease increases the risk of developing coarctation.

3️⃣ Maternal Illness or Exposure During Pregnancy
Exposure to harmful substances such as certain unapproved heart medications, alcohol, or smoking.
Maternal viral infections during early pregnancy (e.g., rubella) can cause heart defects.

4️⃣ Rare Causes
Some cases have no clearly identifiable cause, often thought to result from a combination of genetic and environmental factors.

Types of Aortic Coarctation in Children (Aortic Coarctation)
Aortic coarctation occurs when a part of the aorta is narrower than normal, affecting blood flow from the heart to the rest of the body. Main types include:

1️⃣ Classic Coarctation
Narrowing usually occurs near the ascending aorta, at the aortic arch, just after the major arteries supplying the head and arms.
This type is most common in older children.

2️⃣ Infantile Coarctation
Narrowing is near the ascending aorta and the ductus arteriosus.
Symptoms usually appear shortly after birth, including difficulty breathing, poor circulation, and feeding problems.

3️⃣ Adult-Type or Late Coarctation
Appears after childhood, sometimes during adolescence or early adulthood.
Narrowing is typically after the major arteries supplying the head and arms.
May remain asymptomatic for a long time but eventually leads to high blood pressure in the upper body and cardiac complications.

4️⃣ Coarctation Associated with Heart Valve or Other Defects
Some children have coarctation along with a narrowed aortic valve (bicuspid aortic valve).
It can also be part of congenital heart syndromes such as Williams syndrome or Turner syndrome.

How Does Aortic Coarctation Affect Children?
In a normal heart, the left ventricle pumps oxygen-rich blood into the aorta, which branches out to supply the entire body.

In children with aortic coarctation, the narrowing reduces blood flow to the areas beyond the constriction. The narrowing is often located after the arteries supplying the head and arms but before the arteries that supply the abdomen, kidneys, and legs. As a result:

Blood flow rich in oxygen to the lower body is reduced.
Organs such as the kidneys, intestines, and liver may suffer damage due to insufficient blood supply.
The left ventricle must work harder, which can weaken the heart muscle over time.
In severe cases, it may lead to heart failure or cardiac arrest.

Diagnosis of Aortic Coarctation in Children

Diagnosing aortic coarctation in children begins with a review of the child’s symptoms and medical history, followed by a thorough physical examination. Children are often referred to a pediatric cardiologist for specialized testing, which may include:

1️⃣ Chest X-ray

Detects heart enlargement or other changes caused by the narrowing.

2️⃣ Electrocardiogram (ECG)

Records the heart’s electrical activity to identify rhythm abnormalities or damage to the heart muscle.

3️⃣ Echocardiography (Echocardiogram / Echo)

Uses sound waves to create a moving image of the heart and its valves.
Most cases of aortic coarctation are diagnosed with echocardiography.

4️⃣ Cardiac Catheterization

A thin tube (catheter) is inserted through a blood vessel to the heart.
Contrast dye is used to visualize the location of the narrowing.
In some cases, the narrowing can be treated during the catheterization procedure.

5️⃣ Cardiac MRI

Provides detailed images of the heart and aorta to determine the exact location and severity of the narrowing.

Prenatal Diagnosis of Aortic Coarctation
Aortic coarctation can sometimes be suspected during pregnancy via routine ultrasound or specialized fetal echocardiography performed by a fetal cardiologist.

Early diagnosis allows families and the healthcare team to plan specialized care immediately after birth.
Preparing a specialized heart team before birth improves outcomes.

⚠️ Important Note:
Diagnosing coarctation prenatally can be challenging because the aorta may appear normal while the ductus arteriosus (a natural blood vessel connecting the pulmonary artery to the aorta) is still open. After birth, when the ductus closes, the narrowing becomes more apparent. Therefore, some cases are only diagnosed after delivery.

Postnatal Diagnosis of Aortic Coarctation
The timing of diagnosis after birth depends on the severity of the narrowing and any associated defects:

1️⃣ If suspected before birth:

The newborn is closely monitored and undergoes tests in the hospital immediately after delivery.
Monitoring includes regular physical exams (pulse and blood pressure in the lower limbs) and echocardiography.

2️⃣ If not suspected before birth:

The coarctation may be detected after an abnormal physical exam or routine newborn pulse oximetry test.
Sometimes, the narrowing is only recognized after the child develops complications such as breathing difficulties or poor circulation.

Symptoms of Aortic Coarctation in Children and Infants

The symptoms of aortic coarctation depend on the severity of the narrowing. Some children may show no signs if the narrowing is very mild. However, if the narrowing is moderate or severe—especially after the closure of the ductus arteriosus—symptoms can appear within the first two weeks after birth.

1️⃣ Infant Symptoms

Rapid heartbeat (tachycardia)
Fatigue or extreme sleepiness
Gray or pale skin
Excessive sweating, especially during feeding
Irritability and difficulty calming the baby
Rapid or irregular breathing
Breathing difficulties
Trouble feeding or poor weight gain

2️⃣ Symptoms in Older Children
Most older children do not show symptoms, and the coarctation is often diagnosed when a doctor detects high blood pressure in the upper body.
Symptoms may appear if upper body blood pressure is very high or lower body blood pressure is very low, including:

Frequent headaches
Nosebleeds
Leg pain during exercise or running

3️⃣ Adult Symptoms
These usually appear in cases where coarctation recurs after a previous repair and may include:

Persistent headaches
Kidney problems
Low energy or fatigue when using the legs
Recurrent miscarriages in women

⚠️ Important Note:
Having these symptoms does not necessarily mean aortic coarctation, as they may be related to other health problems. A definitive diagnosis must be made by a pediatric cardiologist.

Diagnosis of Aortic Coarctation in Children

Diagnosis relies on a combination of clinical examination and imaging tests to determine the type and severity of the narrowing accurately.

1️⃣ Clinical Examination

Blood pressure in limbs: High blood pressure in the arms with low pressure in the legs may indicate narrowing after the major arteries.
Pulse: Weak or delayed pulse in the legs compared to the arms.
Heart sounds (murmur): A murmur may be heard when blood flows through the narrowed section.
General symptoms: Rapid fatigue, shortness of breath, feeding difficulties, or delayed growth in infants.

Diagnostic Tests

2️⃣ Electrocardiogram (ECG)

Detects left ventricular hypertrophy caused by increased pressure before the narrowing.
Shows any disturbances in the heart’s electrical activity.

3️⃣ Chest X-ray

Reveals heart size and the shape of major arteries.
May show signs of aortic enlargement or the classic “3 sign” at the site of narrowing.

4️⃣ Echocardiography (Ultrasound of the Heart)

The most important tool for diagnosing coarctation in children.
Determines the location and severity of narrowing and its impact on the left ventricle.
Detects associated heart defects, like a bicuspid aortic valve.

5️⃣ Cardiac MRI or CT Angiography

Provides detailed images of the location and length of the narrowing.
Useful for surgical or catheter-based treatment planning.

6️⃣ Cardiac Catheterization

Sometimes used to measure blood pressure directly across the narrowing.
Can also be used to repair the coarctation via catheter in suitable cases.

Treatment Options for Aortic Coarctation

Treatment depends on several factors:

Age and general health of the child
Severity and location of the narrowing
Child’s tolerance for medications or procedures
Doctor’s expectations of the defect’s progression
Parents’ preferences

1️⃣ Surgical Treatment

Performed under general anesthesia.
Involves removing the narrowed section of the aorta or widening it using a patch or nearby tissue.
The child is then monitored in the ICU for heart function and vital signs.
Surgical repair aims for a permanent correction and to prevent future complications.

2️⃣ Cardiac Catheterization

Performed under anesthesia.
A thin, flexible catheter is inserted from the groin to the heart.
A balloon is passed through the narrowed section to widen it.
In some cases, a stent is placed to keep the aorta open.
Less invasive than open surgery, often used in older children or suitable cases.

3️⃣ Pre- and Post-Treatment Care

Some infants may require intensive care before surgery if symptoms are severe.
After the procedure, monitoring devices track blood pressure, heart rate, and breathing.
Continuous follow-up with a pediatric cardiologist ensures proper recovery and heart function.

Postoperative Care in Children

Monitoring Equipment:

Ventilator: Helps the child breathe during anesthesia and sometimes after surgery.
IV lines: Deliver fluids and medications for recovery.
Arterial line: Continuously monitors blood pressure.
NG tube: Removes stomach acid and gas.
Urinary catheter: Measures urine output to monitor heart and kidney function.
Chest tube: Drains blood or fluid after surgery.
Heart monitor: Continuously tracks heart rate, blood pressure, and vital signs.

Medications:

Pain relief and sedation as needed.
Parents’ input may be requested on comfort measures.

Recovery after ICU:

Child moves to a regular hospital unit for a few days.
Parents learn home care: medications, activity restrictions, follow-up appointments.

Types of Surgical Repair via Thoracotomy

1️⃣ Resection with End-to-End Anastomosis

Best for small narrowing.
The narrowed part is removed and the ends reconnected.

2️⃣ Resection with Extended End-to-End Anastomosis

Used for larger narrowing or underdeveloped aortic arch.
The descending aorta is connected to the arch with an extended repair.

3️⃣ Subclavian Flap Aortoplasty

Expands the aorta using tissue from the subclavian artery.
Rarely used now due to reduced blood flow to the left arm.

4️⃣ Patch Aortoplasty

Uses an artificial patch to widen the aorta.
Rarely used today due to risk of aneurysm formation later.

Cardiac Catheterization Repair

Less invasive than open surgery.
Catheter inserted through a blood vessel in the groin or arm.
Balloon may be inflated to widen the narrowing.
Sometimes a stent is placed to keep the artery open.
Suitable for older children or recurrent coarctation.
Shorter recovery than open surgery.

Catheterization Options:
1️⃣ Balloon Angioplasty

Catheter with a balloon inflates at the narrowing.
Improves blood flow and reduces heart pressure.

2️⃣ Balloon Angioplasty with Stent Placement

After expansion, a metal stent is placed.
Keeps the aorta open longer.
Used for long or severe narrowing or persistent pressure differences after a previous procedure.

Potential Complications

1️⃣ Recoarctation – narrowing may recur

After surgery: 5–10%
After balloon catheter: 11–15%

2️⃣ Aortic Aneurysm – bulging of the aortic wall

3️⃣ Pseudoaneurysm – localized leakage inside the aortic wall

4️⃣ Scar Tissue – may cause re-narrowing, especially after emergency surgery in infants

Preparing for a Pediatric Cardiology Appointment

1️⃣ Track Symptoms – record all symptoms, even minor ones, including onset and frequency.
2️⃣ List Medications – include vitamins and supplements.
3️⃣ Medical & Family History – note any congenital heart defects in the family.
4️⃣ Prepare Questions – leave space for notes and doctor’s answers.
5️⃣ Check Heart Centers – use online tools (e.g., Conquering CHD) to gather information.

Long-Term Outlook after Repair

Most symptoms resolve quickly after correction.
Children typically live healthy, normal lives.
Activity, appetite, and growth usually return to normal gradually.
Recurrent narrowing may require another balloon or surgery.
Pediatric cardiologist may recommend antibiotics to prevent endocarditis and guidelines for safe physical activity