Congenital heart defects in children -- types and symptoms

Congenital heart defect means an abnormality problem in the structure of the heart. As the term congenital suggests, the defect is present at birth, that is, the baby is born with a defect in his /her heart. The problem can be in the walls or the valves of the heart, or the defect can be with the arteries and veins. Congenital heart defects (CHD) affect more than 1,310,000 newborns every year and account for a high proportion of infant deaths worldwide [1]. In India, prevalence of CHD is 19.14 per 1000 individuals, with 58 percent of CHD cases diagnosed between 0 and 5 years of age. [2]

Many of the heart defects may not need treatment. Others can be serious. So if you see any of the symptoms given below or if you feel something is not right with your baby, get in touch with your paediatrician immediately.

Symptoms of CHD

The paediatrician will first look for signs to diagnose CHD by giving the child a physical examination.

Listed below are some common symptoms. [3]

• Flared nostrils: Some defects in the heart can stress the lungs, leading to difficulty in breathing, and the degree of difficulty can be determined by the flaring of nostrils when the child breathes. Nostrils tend to open wider when the lungs are working harder than normal.
• Cyanotic lip: If the inside of the lips turn blue or purple, it means the oxygen levels in the blood is low. Low oxygen levels means there is a defect in the heart.
• Visible veins and arteries in the neck: The blood vessels become visible when the heart is not pumping blood efficiently.
• Retraction of lung muscle: It is the inward pulling of lung muscle, that you see when the muscles between or below the ribs are pulled inward, each time the child breathes.
• Abnormal sound in the chest: Murmurs, clicks, or beats may indicate the presence of heart defect. Crackle-type noise because of fluid accumulation in the lungs is also indicative of heart defect.
• Swelling of the abdomen because of water retention and an enlarged liver, both are signs of CHD.
• Too weak or very strong pulse in the arm or legs can also be indicative of CHD.
• Cool skin: When there is a problem with blood flow in the blood vessels or the heart is not pumping enough blood, the body automatically switches to save mode by restricting blood flow to non-essential areas such as the hands and legs and skin, thus lowering the temperature of the skin.
• Blue or purple or widened nails.
• Slow growth and development in the child.
• Less active physically.

How does the heart work?

Here is a cheat sheet on how the heart works.

• The heart is divided by walls (septum) into four chambers.
• Upper two chambers are called left atrium and right atrium, and lower two chambers are called left ventricle and right ventricle.
• Atria receive blood, while ventricles pump blood out of the heart.
• Deoxygenated blood from other parts of the body enters right atrium and passes through the tricuspid valve into the right ventricle.
• From the right ventricle the deoxygenated blood passes into pulmonary artery through pulmonary valve.
• Pulmonary artery takes the blood to the lungs where oxygen in the lungs attaches to the blood and becomes oxygenated blood.
• Oxygenated blood, then, is carried to the heart by pulmonary vein where it enters the left atrium.
• From the left atrium, the oxygenated blood passes into left ventricle through mitral (bicuspid) valve.
• Oxygenated blood, then, enters the ascending aorta through the aortic valve, which then takes the oxygenated blood to each and every part of the body via arteries.

Types of congenital heart defects

There are different types of congenital heart defects depending upon where the problem lies. It is categorized as follows:

I. Hole in the heart

Atrial septal defect: It is a hole in the dividing wall of the upper two chambers (atria) of the heart. Because of the hole, the oxygen rich blood goes from the left atrium to the right one, instead of the left ventricle. The oxygenated blood mixes with the deoxygenated blood, so not enough oxygen is circulating in the child s body. The baby s skin and fingernails may become blue because of this. The child may also symptoms of swelling in the legs and shortness of breath. Read more about 7 innovative ways to keep your child s heart healthy

Ventricular septal defect: Here, the hole is in the septum dividing the two ventricles and blood flows in from the left ventricle to the right one. The hole can be small, medium, or large. In case of large holes, lot of blood flows from the left ventricle causing an increase in blood pressure on the right side of the heart. It makes the heart work harder and can lead to heart failure and poor growth.

Patent Ductus Arteriosus:This condition occurs when there is mixing of the blood because of a hole between the pulmonary artery and the aorta. The defect can be identified by the heart murmur. Other signs include shortness of breath, and profuse sweating with exertion.

II. Narrowed or abnormal valves restricting blood flow

Pulmonary stenosis: In this case, the valve that allows the blood to pass from the right ventricle to the pulmonary artery, thickens, stiffens, or fuses together, so the valve cannot open fully. This causes the heart to pump harder, so that blood can pass into the pulmonary artery. In mild cases, the child shows no signs and may not need treatment, but when the stenosis is severe, the baby can feel very tired, does not feed properly, and shows signs of heavy breathing. To know more How to care for a baby with congenital heart disease

Aortic stenosis: Here, the aortic valve becomes too narrow to allow blood to flow properly from the left ventricle to the aorta. This condition shown no visible signs and less severe cases do not need treatment. Severe forms of aortic stenosis may require catheter procedure or valve surgery. Recent research however suggests valve surgery to be the best approach to treat aortic stenosis in infants and newborns. [4]

Ebstein s anomaly: In this type of heart defect, the tricuspid valve, that separates the right atrium from right ventricle, is deformed causing the blood to flow back into the atrium instead of going to the lungs. In severe cases, surgery may be required to correct the valve.

Pulmonary atresia: Here, the pulmonary valve which regulates blood flow from the right ventricle to the lungs is malformed. Depending on the extent of the defect, following treatments are recommended.

• Medicine called Prostaglandin E1
• Heart catheterization
• Open heart surgery
• Heart transplant

III. Abnormal blood vessels

Transposition of the great arteries: This is a serious congenital condition where the two main arteries - pulmonary artery and the aorta - are switched in position. Here, the oxygenated blood does not get to the rest of the body resulting in bluish coloured skin and shortness of breath. Surgery has to be done shortly after birth as it can prove fatal within 6 months.

Coarctation of the aorta: It is a heart defect that accounts for 5 to 8 percent of all heart defects. Here, the aortic wall thickens causing narrowing of the aorta. Coarctation of the aorta causes high blood pressure that needs to be monitored life long. However, significant advances in surgical techniques have evolved to the point of almost no deaths. [5]

Hypoplastic left heart syndrome: This is a defect in which the left side of the heart does not develop properly. So, it cannot pump oxygenated blood effectively to the body parts.

IV. Combination of heart defects

Tetralogy of Fallot:It is a rare, complex defect that is a combination of four heart defects, namely, ventricular septal defect, pulmonary stenosis, overriding aorta (where the aorta appears to arise from both ventricles instead of the left ventricle as it should), and right ventricular hypertrophy (thickening of right ventricular wall). Children with tetralogy of Fallot show signs of cyanosis (blue tinge to skin, nails, and lips), and become over-tired or limp. An open heart surgery is the treatment for this heart defect. When the surgery is performed depends on how far the pulmonary artery is blocked. Usually the surgery is done within first six months of the baby s age. With the greatly improved surgical techniques, most children grow up into adulthood, but they would require lifelong medical care. Know more about 7 symptoms of congenital heart disease

Why do heart defects occur?

The heart begins to take shape in the first 6 weeks of pregnancy, so that is the time when the heart defects occur. For example, the dividing wall in the heart starts to form in week-5, so that is when any abnormality in the wall can happen. Most of the CHDs have no known cause and scientists are still searching to find out what exactly causes CHD. However, scientists think that there is a genetic and environmental link to some heart defects. Many experts believe there is also a link between congenital heart defects, and maternal smoking and alcohol consumption. Although recent studies have not found a little drinking to be associated with CHD [6], smoking is definitely linked to CHD. Researchers found that maternal smoking was most strongly associated with pulmonary valve and pulmonary artery anomalies, and atrial septal defects. [7]

Children with congenital heart defect may continue to have emotional and developmental difficulties even after treatment. As a parent, you can talk to your child s doctor about how you can help your child cope with his /her problems.

References

1. Hoffman JI. The global burden of congenital heart disease. Cardiovascular Journal of Africa. 2013;24(4):141-145. doi:10.5830/CVJA-2013-028.
2. Bhardwaj, R., Rai, S. K., Yadav, A. K., Lakhotia, S., Agrawal, D., Kumar, A. and Mohapatra, B. Epidemiology of Congenital Heart Disease in India. Congenital Heart Disease, 2015. 10: 437 446. doi: 10.1111/chd.12220.
3. ZENG Z, ZHANG H, LIU F, ZHANG N. Current diagnosis and treatments for critical congenital heart defects. Experimental and Therapeutic Medicine. 2016;11(5):1550-1554. doi:10.3892/etm.2016.3167.
4. Siddiqui J, Brizard CP, Galati JC, et al. Surgical Valvotomy and Repair for Neonatal and Infant Congenital Aortic Stenosis Achieves Better Results Than Interventional Catheterization. J Am Coll Cardiol. 2013;62(22):2134-2140. doi:10.1016/j.jacc.2013.07.052.
5. Vergales JE, Gangemi JJ, Rhueban KS, Lim DS. Coarctation of the aorta - the current state of surgical and transcatheter therapies. Curr Cardiol Rev. 2013;9:211 219.
6. Wen Z, Yu D, Zhang W, et al. Association between alcohol consumption during pregnancy and risks of congenital heart defects in offspring: meta-analysis of epidemiological observational studies. Italian Journal of Pediatrics. 2016;42:12. doi:10.1186/s13052-016-0222-2.
7. Sullivan PM, Dervan LA, Reiger S, Buddhe S, Schwartz SM. Risk of congenital heart defects in the offspring of smoking mothers: a population-based study. J Pediatr. 2015 Apr;166(4):978-984.e2. doi: 10.1016/j.jpeds.2014.11.042. Epub 2015 Jan 9.

Image source: Shuterstock (Image for representational purpose only)

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