Truncus Arteriosus Treatment in Delhi, India

A single large vessel known as truncus arteriosus exits the heart during the fetus's development. Truncus arteriosus is a rare condition of the heart that is congenital or occurs at birth. It occurs when a single blood vessel comes out of the ventricles instead of the usual two -known as the pulmonary artery from the right ventricle and the aorta from the left ventricle.

In babies with truncus arteriosus, this single large vessel never divides into two separate vessels. As a result, the wall separating the blood vessels is not closed completely. Babies with truncus arteriosus often have ventricular septal defects (VSD), which is a hole in the heart wall. This congenital heart defect allows too much blood to go into the lungs, which forces the heart and lungs to work harder. Truncus arteriosus is a life-threatening condition and requires surgery shortly after birth.

Symptoms

Babies born with truncus arteriosus often show signs of distress soon after birth. This is primarily because the heart works too hard to pump blood to the body. Some of the symptoms of this congenital heart defect include:

• Poor feeding
• Shortness of breath
• Pounding heart
• Rapid breathing
• Blue colouring of the skin
• Excessive sleepiness
• Poor growth
• Fatigue
• Widening of the fingertips
• Sweating
• Heart murmur
• Unresponsiveness

Causes

The exact cause of the truncus arteriosus is not known at the moment. With truncus arteriosus, a single artery comes out of both the right and left ventricles. There is also a hole between the two ventricles that causes the oxygen-poor and oxygen-rich blood to mix up. Some of this mixed blood goes to the lungs, and some to the rest of the body.

However, in some cases, the mixed blood goes to the lungs more often, which causes a build-up of extra fluid around the lungs. This makes it difficult for the heart to pump blood from the lungs. This may also cause pulmonary hypertension, which is a life-threatening condition. It can also become inoperable due to obstructive PAH.

Diagnosis

Truncus arteriosus is usually diagnosed at birth. The doctor performs a physical examination to check for any heart murmur or sees a blue tint on the lips or skin. The doctor may advise the following tests to confirm the severity of truncus arteriosus. These may include:

• Echocardiogram: This is the preliminary test done to diagnose truncus arteriosus. During the procedure, the surgeon uses sound waves to produce heart images on a monitor. The test shows the single large vessel that leads from the heart or any other anomalies.
• Chest X-ray: The chest X-ray helps see the heart and lungs to check whether there is an accumulation of fluid in the lungs.
• Cardiac Catheterization: In this test, the medical expert inserts a catheter into the blood vessel and guides it to the heart. A dye is then released to check for any hole in the wall, along with the presence of a single large vessel.
• Electrocardiogram: The test is done to measure the duration and timing of the heartbeats.

Treatment

In most cases, surgery is the only option to treat the truncus arteriosus condition. However, depending on the condition of the baby, the doctor may suggest the following treatment:

Surgery

Most infants suffering from truncus arteriosus need to have surgery in the first few weeks after birth. During the open-heart surgery, the surgeon makes incisions around the chest and places a patch to close the hole in the heart wall. The surgeon then separates the pulmonary arteries from the trunk and connects them to the heart's right ventricle using special kinds of conduits (tubes).

The surgeon then reconstructs the single large vessel and creates a new aorta connected to the left ventricle. After the surgery, the child needs life-long follow-up care with a cardiologist. The child will be given antibiotics and other medications. A child may need two or three surgeries to replace the conduits as their heart and body grow.

Medications

Some of the medications that may be necessary for the child includes:

• Diuretics prevent fluid from building in the body by increasing the frequency and volume of urination.
• Angiotensin-converting enzyme inhibitors make it easier for the heart to pump blood.
• Decongestants to help strengthen the heart muscle.

Risk Factors

Although the exact reason for truncus arteriosus is unknown, several factors may increase the risk of babies born with a heart condition. These may include:

• Viral illness during pregnancy
• Poorly-controlled diabetes during pregnancy
• Smoking
• Alcohol abuse during pregnancy
• Obesity
• Chromosomal disorders
• Certain medications

Prevention

In most cases, truncus arteriosus defect cannot be prevented. However, one can take a few steps before and during the course of pregnancy to ensure the baby's health. These may include:

• Get vaccination before pregnancy. Certain viruses like German measles can be harmful to the baby during pregnancy. So, it is essential to get vaccinated before planning to get pregnant.
• Take folic acid. Taking 400 micrograms of folic acid daily helps prevent congenital disabilities.
• Control diabetes. Women with diabetes during pregnancy may result in heart defects in the baby. So, it is advisable to talk to the doctor and learn how to control diabetes during pregnancy.

Complication

Truncus arteriosus can cause some severe complications with blood circulation. This is primarily because the blood is mixed and exits from a single vessel, making it harder for the heart to pump it to the body. Babies suffering from truncus arteriosus have a higher risk of the following complications:

• Heart Failure
• Endocarditis
• Cardiomegaly
• Respiratory Problems
• Pulmonary Hypertension
• Heart Valve Problems
• Lung Problems
• Poor Growth and Development

Outlook for Patients

The outlook for babies that have gone through complete surgical repair of the heart often has good results. The child will have an active life, though he may be under continuous observation by a pediatric cardiologist. Therefore, the child will need to see a cardiologist throughout their life. That said, untreated cases of truncus arteriosus can be fatal, and the child will not be able to survive during the first year of life.

Review

Reviewed by Dr. Mily Ray, Consultant, Paediatric (Ped) Cardiology.