Enlarged Heart in Babies – Causes, Diagnosis and Treatment

The human heart is the organ responsible for regulating the blood flow in the human body. Sometimes babies are born with a defective heart, or more appropriately, a defect in the structure of their heart, which has an adverse effect on its functioning. One of the signs of a heart defect is an enlarged heart. Read this article to know the causes of an enlarged heart in a baby, its diagnosis and treatment. But first, let’s quickly go through what a human heart comprises of. It will help you understand the topic better.

The human heart comprises of two sides divided by a wall also known as the septum. There are two simultaneous processes that the heart performs with every beat. Every heartbeat results in oxygen-poor blood pumped into the lungs through the right side of the heart. The left side of the heart pumps blood rich in oxygen into the body. The inner wall or the septum keeps the oxygen-rich blood separate from the oxygen-poor blood by forming a physical barrier between the different sides of the heart.

Now, let’s get to know what an enlarged heart in a baby is.

What Is an Enlarged Heart?

An enlarged heart is not a condition or a heart defect by itself; mostly it is a sign or a symptom of a heart defect. Some babies get diagnosed with an enlarged heart, which, when abnormal, is most likely due to an underlying congenital heart defect, such as a hole in the heart, a problem with the valves of the heart, problems with the big vessels like pulmonary artery and aorta or hypertension.

Though the most common finding of an enlarged heart is an underlying heart defect, in some rare cases, the heart may be enlarged even in the absence of the heart defect. Getting the evaluation done by x-ray, ECG and Echocardiography is a must by a pediatric cardiologist to know further.

What Is Meant By a Hole in the Heart?

Sometimes babies are born with a hole in the inner wall or the septum, these holes connect the separate chambers of the heart and interfere with the manner in which blood carries oxygen to and from the heart.

In simpler terms, holes in the heart are referred to as congenital heart defects. With advancements in medical knowledge and technology, children diagnosed with congenital heart defects can survive and grow to live a normal life since these defects can heal on their own in due time. Therefore, the survival rate of a baby born with a hole in the heart is exceptionally high.

Types of Holes in the Heart

A hole in the heart is categorised depending on its position. When the hole is in the upper part of the septum and between the two upper chambers in the heart, it’s called an atrial septal defect or ASD. If the hole is in the lower septum between the two lower chambers, it is known as a ventricular septal defect or VSD.

In either case, the blood from two different chambers in the heart mix resulting in some oxygen-poor blood being pumped into the body instead of the lungs and some oxygen-rich blood being pumped back into the lungs instead of the body.

Read on to know both these defects a little more in detail.

1. Ventricular Septal Defect (VSD)

A ventricular septal defect can be described as a hole or an opening in the septum that separates the left ventricle from the right ventricle. The two lower chambers of the heart are called ventricles. This hole or opening results in the flow of oxygen-rich blood from the left to the right ventricle. Under ideal circumstances, the oxygen-rich blood from the left ventricle should flow into the body via the aorta. However, when this does not happen, it is a case of ventricular septal defect or VSD.

Possible Causes:

Medical science has no definitive answer to what causes heart defects at birth. There are, however, certain probable causes for the same. The first of these probable causes is that congenital heart defects may be hereditary. It has been observed that parents with congenital heart defects are more likely to pass on this complication to their children. Genetic disorders have also been known to cause congenital heart defects. Down syndrome, for example, is a genetic disorder; most children born with Down syndrome suffer from congenital heart defects. Tobacco abuse is also known to cause VSD in babies, particularly if women indulge in smoking while pregnant.

Signs and Symptoms of VSD in Babies:

Babies with VSD could show the following signs and symptoms other than an enlarged heart:

• A routine check-up during the first few weeks could help identify VSD in babies affected by it. When blood flows between the left and right ventricles, it produces a unique sound or vibration known as a heart murmur. The murmur associated with a VSD is unique, and the doctor would identify it as opposed to a murmur caused by other factors.
• In case of moderate to large VSDs, a baby may breathe faster than usual and show signs of exhaustion while feeding.
• A baby with a VSD may tend to break into a sweat or start crying while being fed.
• A baby with a VSD may gain weight very slowly.

Diagnosis:

• If a heart murmur is observed, the doctor may suggest consulting a paediatric cardiologist.
• A paediatric cardiologist will study the child’s medical history and conduct a medical examination.
• The cardiologist may suggest a chest X-ray or an electrocardiogram, which tests the electrical activity of the heart.
• The cardiologist may also ask for an echocardiogram, which will help create an image of the heart using sound waves. This test will also reveal vital information such as the structure of the heart, blood flow through the chambers of the heart, blood pressure and blood oxygen levels.
• If additional information is required, cardiac catheterization may be performed to measure the level of blood oxygen in the heart and the blood pressure.

Complications:

• If the VSD is medium or large, the baby’s heart will need to pump harder. This could lead to heart failure. In case of a VSD, the left side of the heart pumps blood both into the right ventricle, and the body, the additional effort by the heart increases the heart rate and the body’s need for energy.
• Retarded growth may be observed in a baby born with a VSD as he won’t be able to feed enough to meet the additional energy requirements of his body.
• A VSD could lead to endocarditis, which is a heart infection.
• Irregular heartbeats and scarring of the blood vessels in the lungs.

Treatment for VSD in a Baby:

• Doctors recommend high-calorie formula and breast milk supplements to meet the extra energy needed for affected babies.
• In the event that a VSD does not heal naturally by the age of one, heart surgery may be recommended to treat the hole in the heart.
• Surgery is also advised if the baby needs to be kept on medication to prevent heart failure, or is failing to gain weight.

Caring for a Baby With VSD:

In case a baby is diagnosed with a small VSD and is displaying no symptoms of the same, parents should take him for regular check-ups to a cardiologist. Proper oral hygiene should also be maintained for a baby who has VSD as bacteria from the mouth may enter the bloodstream and cause an infection in the inner linings of the heart. The doctor may also prescribe antibiotics to the baby before any medical or dental procedure is recommended to avoid any infections in the heart. Regular visits to the paediatrician are recommended to check for normal growth and development. Play and other activities should be initiated only as per the instructions of the doctor.

2. Atrial Septal Defect (ASD)

The two upper chambers of the heart are called atria. An atrial septal defect in infants can be described as a hole or an opening in the part of the septum which keeps the left and the right atrium separate. It allows the oxygen-rich blood from the left atrium to enter the right atrium. Under ideal circumstances, the oxygen-rich blood from the left atrium should flow into the body and not back into the lungs. If it doesn’t, it is an atrial septal defect or ASD.

Possible Causes:

The probable causes of ASD are similar to the probable causes of VSD as mentioned above. Some babies may have heart defects because of the changes in their chromosomes or genes.

Signs and Symptoms of ASD in Babies:

Babies with ASD could show the following signs and symptoms other than an enlarged heart:

• A baby with ASD may have difficulty while breathing.
• He may feel lethargic and tired.
• Blood and fluids may accumulate in his lungs.
• Accumulation of fluid in feet, legs and ankles.

Diagnosis:

• If a heart murmur is noticed, the doctor may suggest you see a paediatric cardiologist immediately.
• A paediatric cardiologist will study the child’s medical history and conduct a medical examination.
• The cardiologist may ask for a chest X-ray or an electrocardiogram, which tests the electrical activity of the heart.
• The cardiologist may also ask for an echocardiogram, which creates an image of the heart using sound waves. This is a primary test for an ASD and will also reveal vital information such as the structure of the heart, blood flow through the chambers of the heart, blood pressure and blood oxygen levels.

Complications:

• In case of an ASD, the right side of the heart is forced to work harder and may eventually result in right-sided heart failure.
• Irregular heartbeats on account of an enlarged right atrium.
• The lungs may not filter out blood clots, which may travel into the body and create blockages in the arteries, leading to a stroke.

Treatment for ASD in a Baby:

• A baby with an ASD should be taken for periodic check-ups to confirm whether the ASD has healed naturally or not.
• With children between two and five years of age still suffering from ASD, doctors may recommend a surgical procedure to eliminate the condition.

Caring for a Baby With ASD:

Congenital heart defects like ASD and VSD may heal on their own or may need intervention immediately or at a later stage. Advances in medical science and technology have greatly improved the diagnosis and treatments of congenital heart defects. Therefore, always follow the paediatrician’s and paediatric cardiologist’s advice and get the cause of the enlarged heart evaluated with a chest x-ray, ECG and Echocardiogram to manage the condition better. Regular checkups are highly recommended for children with ASD to check for normal growth and development. Play and other activities should be initiated only as per the instruction of the doctor.

This information should be able to help you get prompt medical attention in case you notice similar signs and symptoms in your little one. Keeping the appointments and ensuring your stress levels are in check are necessary through the diagnosis and treatment, but be assured that medical science can help manage the condition and bring about wondrous results.

References and Resources: MayoClinic