Coarctation of the aorta (CoA) is a condition where a part of the aorta becomes narrow or constricted. Aorta is a blood vessel that carries blood from the left ventricle to other vessels in the body. The narrowing may occur in the aortic arch or the thoracic or abdominal aorta, compromising the blood supply to the corresponding body parts.
CoA is seen in 6-8% of babies with congenital heart diseases (1). This is the leading cause of systemic hypertension (increased blood pressure) in children. If left untreated, coarctation of the aorta can be life-threatening in severe cases.
Read this post to know about the symptoms, causes, risk factors, complications, and treatment of coarctation of aorta in babies.
Signs And Symptoms Of CoA In Babies
The signs and symptoms of coarctation of the aorta are apparent within the first few days of life in severe cases (2). The severity of symptoms may depend on the degree of aorta narrowing. Babies with moderate and severe coarctation of the aorta may have the following signs and symptoms.
- Heavy sweating
- Rapid or labored breathing
- Poor growth
- Gray or pale appearance
- Weak pulse in the femoral artery (groin area)
- Heart murmurs heard in the stethoscope
Mild narrowing of the aorta may go unnoticed in babies, and symptoms may appear during late childhood or adulthood. These symptoms may include the following.
- Dizziness and fainting
- High blood pressure
- Cold leg and feet
- Exercise intolerance such as become breathless quickly
- Leg cramps
- Heart murmur
You may consult a pediatrician if your baby has any of the symptoms mentioned above. Early interventions prevent heart complications and delay in growth and development in babies.
Risk Factors And Causes Of CoA In Babies
The exact cause of coarctation of the aorta is not known in most babies (3). Changes in chromosomes or genes can cause CoA and other congenital heart defects in some babies. Environmental factors and maternal factors, such as maternal infections, health conditions, and lifestyle, may also play a role in developing congenital heart diseases in babies.
Other Congenital Cardiac Defects Associated With CoA
Babies with coarctation of the aorta may have other congenital heart defects too. The following defects are more commonly seen in babies with CoA (4).
- Bicuspid aortic valve: This is a condition where the aortic valve has only two flaps instead of three. The aortic valve separates the left ventricle (lower left chamber) of the heart from the aorta. This may interfere with normal blood supply from the heart to the body.
- Patent ductus arteriosus: This is the failed closure of the blood vessels called ductus arteriosus that connect the aorta and left pulmonary artery before birth. These blood vessels allow bypassing the blood from the lung during the fetal period and usually close immediately after birth.
- Congenital mitral valve stenosis: Some babies may have narrowed mitral valves from birth. This valve is located between the left and right ventricle. When blood flow from the left atrium to the left ventricle is not normal, it may cause backflow of blood from the left atrium to the lung, leading to lung congestion. Reduced flow to the left ventricle may affect blood flow in the body.
- Holes in the septum: Some babies can have holes in the wall between heart chambers. This can be between upper chambers (atria) called atrial septal defect (ASD) and lower chambers (ventricles) called ventricular septal defect (VSD). These openings may cause mixing of oxygenated and deoxygenated blood on both sides of the heart, resulting in insufficient oxygen supply and other complications.
- Subaortic stenosis: This is also called sub valvular aortic stenosis (SAS), a rare condition seen in infants. In this condition, a membrane, usually a muscular tissue, obstructs blood flow from the left ventricle below the aortic valve and compromises blood supply in the body.
CoA can also be associated with genetic conditions such as Turner’s syndrome and other heart problems. Babies with ASD and different congenital heart conditions may have more prominent symptoms and often require immediate repair.
Possible Complications Of CoA
The following complications are associated with coarctation of the aorta before, during, or after the repair (5).
- Aneurysm (ballooning out) of the aorta
- Aortic rupture or tear in the aortic wall
- Brain hemorrhage
- Early coronary artery disease (CAD)
- Heart failure and endocarditis (infection of the inner layer of the heart)
- Kidney problems
- High blood pressure
- Paralysis of the lower body is a rare complication of CoA repair surgery
Repeated or continued narrowing of the aorta, endocarditis, and increased blood pressure are long-term complications of CoA. Antibiotic prophylaxis is recommended for babies with CoA before any dental procedure to prevent endocarditis. You may tell the dentist about the heart tissue repair before the procedures in the future.
Prevention Of CoA In Babies
Coarctation of the aorta cannot be prevented in most cases since it is present at birth (4). Early diagnosis and treatment may prevent complications in most babies. Promoting a healthy lifestyle with a balanced diet and physical activity and doing follow-ups as per schedule may prevent recurrence and other complications after surgical repair (6).
Diagnosis Of CoA In Babies
A heart murmur heard during a physical examination can be a diagnostic point of CoA in many babies. Pediatricians may refer babies with murmurs and other cardiac symptoms to a pediatric cardiologist for detailed evaluation. Murmurs are sounds of abnormal blood flow in the heart. Loudness, location, timing, and quality of murmur can give ideas about heart problems.
Doctors may order the following tests based on an initial evaluation to confirm the diagnosis of CoA in babies (7).
- Electrocardiogram (ECG) records the electrical activity of the heart. This helps determine arrhythmia (abnormal heart rhythm) and myocardial (heart muscle) damages.
- Chest X-rays may often give information about pulmonary involvement and the size of the heart.
- Echocardiogram is the gold standard in diagnosing heart defects since it determines the structure and function of the heart. This uses sound waves to visualize the heart.
- Magnetic resonance imaging (MRI) scan is also used to visualize the cardiac structures in detail.
- Computed tomography (CT) scan uses X-rays to create a cross-sectional view of the heart.
- CT angiogram uses special dyes to show the blood vessels.
- Cardiac catheterization may also be used for the diagnosis of CoA in some cases. This may provide more details about the severity of CoA.
Treatment For CoA In Babies
CoA treatment may vary based on the severity of symptoms, age, and health status of the baby (8). Fixation of narrowed vessels is the standard treatment for coarctation of the aorta. CoA can be fixed through the following procedures.
- Open heart surgery involves a chest incision to reach the heart. The procedure is conducted under general anesthesia. The narrowed area of the aorta is removed or widened, and the two ends of the aorta are connected during this surgery. Nearby tissues or patches are often used to make the aorta longer. Open heart procedures are usually performed in severe cases or when the baby has multiple heart defects.
- Cardiac catheterization and balloon angioplasty use a catheter inserted from peripheral blood vessels to the narrowed part of the aorta. During this procedure, the balloon on the tip of the catheter opens and stretches the aorta, and doctors may place a stent (metal mesh tube) in the narrowed area to keep it open.
Medications are not used to repair CoA in babies. Doctors may often prescribe medications to control blood pressure and keep the ductus arteriosus open. This may ensure blood supply around the constriction until the repair procedure.
Outlook Of CoA In Babies
Coarctation of the aorta is curable with surgery (5). Babies may have quick improvement of symptoms after the repair. However, there can be a risk of life-threatening heart issues even after the repair. Therefore, lifelong follow-up is recommended to ensure a good prognosis.
Although the surgeries are usually done in infancy, it may be delayed in some cases. However, doctors recommend surgery no later than age ten since untreated cases may endanger life by age 40. In addition, newborns with repaired CoA may still have the risk of recurrence of the condition in the future.
Coarctation of the aorta can be associated with other heart defects in many babies. Correction of the condition is necessary since lack of blood supply can impact a baby’s growth and development. You may also inform the doctors about the history of CoA repair before medical or dental procedures in the future.