Causes and treatment of congenital heart defects in babies

Congenital heart defects are the most common type of birth defect in babies. According to the Centre for Disease Control, congenital heart defects are usually present at birth. They affect the structure of the baby’s heart and the way the heart works. “They can also affect blood flow through the heart and out to the rest of the body,” says CDC.

According to the CDC, heart defects vary from a small hole in the heart which is classified as a mild heart defect to missing or poorly formed parts of the heart which is classified as a severe heart defect. According to Dr. Sean Del-rossi, a Consultant Paediatric Interventional Cardiologist at Aga Khan University Hospital, Nairobi, holes in the heart can form in the walls between heart chambers or between major blood vessels leaving the heart. “These holes allow oxygen-poor blood to mix with oxygen-rich blood, resulting in less oxygen being carried to a child's body,” he says. “Depending on the size of the hole, this lack of sufficient oxygen can cause a child's skin or fingernails to appear blue or possibly lead to heart failure.” With congenital heart defects, your baby could be at risk of obstructed blood flow. This obstruction of blood flow will force the heart to work harder than normal in order to get the baby’s blood moving. “When blood vessels or heart valves are narrow because of a heart defect, the heart must work harder to pump blood through them,” he says.

The CDC lists the most severe congenital heart defects as follows:

• Coarctation of the Aorta
• Double-outlet Right Ventricle
• d-Transposition of the Great Arteries
• Ebstein Anomaly
• Hypoplastic Left Heart Syndrome
• Interrupted Aortic Arch
• Pulmonary Atresia
• Single Ventricle      
• Tetralogy of Fallot
• Total Anomalous Pulmonary Venous Return
• Tricuspid Atresia
• Truncus Arteriosus

According to the CDC, noncritical congenital heart diseases are:

• Ventricular Septal Defect
• Atrial Septal Defect
• Atrioventricular Septal Defect

Signs and symptoms

The type of heart defect a baby has will determine the signs and symptoms he or she will exhibit. They can range from blue-tinted nails or lips, fast or troubled breathing, tiredness when feeding, and sleepiness. The Centre for Disease Control however cautions that some defects will have little to no symptoms and may require a professional medical diagnosis to spot them. The baby may also have bluish discolouration of lips, fingers, or tongue, recurrent chest infections with rapid or difficult breathing during activities, and poor weight gain.  The baby may have swollen legs, hands, and abdomen, or swelling around the eye.

The causes

According to Del-rossi, some congenital heart defects usually start to develop during the first six weeks of pregnancy. This is the period within which the baby’s heart begins to develop and form a shape and begin beating.

“The actual causes of heart defects are unknown, but there are certain risk factors that have been shown to predict the occurrence of heart defects,” he says. For example, if there is a family history of heart defects, Dr. Del-rossi says there will be a 2 to 3 percent chance of having a child with a congenital heart defect. “Prescription medications for illnesses such as epilepsy can also result in congenital heart diseases in expectant mothers. Mothers with a viral infection like rubella during the first trimester of pregnancy are also more likely to give birth to a child with a heart abnormality,” he explains. In addition, expectant mothers who consume alcohol, or illegal drugs during pregnancy are at an increased risk of having babies who have heart disease. “Women suffering from diabetes, or obesity have a high chance of giving birth to children with a congenital heart defect, while problems with genes or chromosomes in a child, such as Down syndrome can also be another risk factor,” says Dr. Del-rossi.

Diagnosis

One of the ways a child’s heart defect can be suspected is through auscultation with a stethoscope during a routine clinical examination. Here, the doctor will hear a heart murmur which is a prime lead to the possibility of a heart defect. This sound could be a blowing, whooshing, or rasping sound. Dr. Del-rossi explains that a heart murmur is an abnormal sound that occurs when blood flows through the heart or blood vessels fast enough to make the sound or murmur that is heard during the auscultation examination. According to the CDC, some congenital defects may be diagnosed during pregnancy. This is done through a special ultrasound exam known as a fetal echocardiogram. This exam creates ultrasound pictures of the heart, enabling cardiologists to make an examination based on the developing foetus. “There are some heart defects, though, that will not be detected until after birth or even until later on during childhood or adulthood,” the CDC cautions.

Treatment and costs

Treatment will vary from one type of defect to the other. In some cases, a baby may only need one heart surgery to correct the anomaly. In others, the baby may need multiple surgeries to repair the heart or blood vessels. According to the CDC, some heart defects can also be treated without requiring surgery. This is done through a procedure known as cardiac catheterization. “During this procedure, a catheter is threaded through the blood vessels into the heart, where the doctor can take measurements and pictures, do tests, or repair the problem,” says the CDC. In some cases, heart defects are not fully cured. However, blood flow and heart functioning are greatly improved to allow the baby to live as normal a life as possible. According to MP Shah Hospital, paediatric heart operations are amongst the most expensive surgeries. The hospital estimates that a single operation costs between Sh. 500,000 to Sh. 1.2 million.

Quick stat

• In Kenya, the Ministry of Health estimates that more than 200,000 children under the age of 18 years suffer from heart disease.
• Each year, over 10,000 babies are born with congenital heart diseases.