A congenital heart defect (birth defect) is a common developmental disorder and structure of the heart ranging from mild to severe. It affects valves, walls, blood vessels, arteries and veins of the heart causing disruption in the flow of blood. The blood can flow slowly or even flow in the wrong direction, leading to serious complications.
According to the Center for Disease Control and Prevention in the US, currently around one million each adults and children are suffering from congenital heart defects in the United States. Treatment and continuous follow up and care can help children live lives that are productive and longer.
Survival rate of children mainly depends on the severity of the defect and the survival rates are improved because of increased and advanced medical care, technologies and preventive measures. These include fetal intervention, diagnosis, advanced neo-natal surgeries for complex or severe congenital heart defects and post-surgery intervention as the child develops and grows.
Heart tests are conducted to diagnose whether the child has the defect and requires treatment or not. Severe defects are usually diagnosed during pregnancy or after the birth of child. The treatment plan for the patient includes medication or surgical, catheter procedures which depends on the severity of the defect, its size, age and the overall physical health of the patient
What are the categories and types of congenital heart defects or disorders?
Congenital heart can be classified into three main categories:
Defects in heart valve: If the valves inside the heart that directs flow of the blood are closed or have leakages, it interferes with the pumping of blood.
Defects in heart wall: It is characterized by incorrect development of walls between the right-left sides and upper-lower chambers of the heart causing back up of blood or backflow of blood in a different direction. It pressurizes the heart, causing it to work harder and leading to high levels of blood pressure.
Defects in blood vessels: When arteries and veins which are responsible for carrying blood to the heart and back to the body are defective, it results in reduced or blocked blood flow, thereby causing several health complications.
What are the signs and symptoms of congenital heart defects?
Congenital heart defects are usually diagnosed during pregnancy through ultrasound imaging or after the birth of a child. Some cases are asymptomatic while others have symptoms which are developed in newborns including the following:
- Heart murmuring sounds when the flow of blood through the blood vessels or heart is very fast and can be heard with a stethoscope
- Breathing problems or swelling
- Dizziness, fatigue or poor circulation of blood
- Bluish appearance in infants (Cyanosis)
- Difficulty in feeding
- Delayed growth or weight gain problem
In adolescents or adults, along with a few of the above symptoms, breathlessness, a reduced ability to exercise and chest pain are often observed.
How is a congenital heart defect diagnosed?
The examinations used to diagnose heart defects include:
Fetal echocardiogram: It checks the defects of heart before the birth of a child.
Echocardiogram: It identifies motion of heart in children and abnormalities of heart valves and muscles.
Electrocardiogram It detects rhythm and defects of a child’s heart.
Chest X-ray: It checks the size of heart, if it is enlarged and if the lungs are carrying extra fluid or blood.
Cardiac catheterization: It examines the heart defects in detail and can be used for treatment when required in some cases.
Cardiovascular magnetic resonance imaging (MRI): It evaluates the heart defects in adolescents or adults for faster imaging.
What are the underlying causes of congenital heart defects?
Certain suspected causes or risk factors for congenital heart disease include the following:
- Genetic disorder or heart defects running in the family
- Use of certain illegal drugs or alcohol during pregnancy
- Viral infections during pregnancy
- Increased blood sugar levels during pregnancy
How is a congenital heart defect treated?
Treatment for heart defects depends on type or severity of the defect, age or physical condition of the child. Some defects get healed on their own while the severe defects require surgical or extensive treatment. There is a wide array of options to treat symptomatic defects which include:
Medications: Medications can help in making heart work efficiently, controlling irregular heartbeats, preventing blood clotting and easing the burden on the heart muscle. These include:
ACE inhibitors (Angiotensin-converting enzyme) and ARBs (Angiotensin II receptor blockers): These classes of medication lower the pressure of blood and relax the blood vessels, making it easier for the heart to pump the blood.
Beta blockers: These medications slow down the heart rate, helping in widening the arteries. These can be Atenolol (Tenormin), carvedilol (Coreg CR), or metoprolol (Lopressor).
Diuretics or water pills: They help in lowering the fluid levels and easing the stress on the heart.
Implantable Heart Devices: Some heart defects are controlled with devices such as pacemakers which regulate abnormal heart rate and implantable cardioverter defibrillators (ICDs) which correct irregular heartbeats that can be life-threatening in nature.
Catheter Procedures: To avoid surgery, catheter procedures can be used to fix holes or narrowing the area of holes. It is performed by inserting a thin tube in the vein of a leg and guiding it up to position it in the heart and then correcting the defects by using small tools which are threaded through the catheter.
In a Cardiac Catheterization procedure, a catheter is inserted with tiny balloon directed towards the valve or artery if it’s not working properly, inflating the balloon to widen the valve or artery. It is also known as valvuloplasty (if performed on a valve) and angioplasty (if performed on an artery)
Catheters are used for various objectives including the following:
- Repairing the holes in the wall separating the left and right sides of the heart;
- Widening narrowed arteries or stiff valves;
- Closing the vessel if the blood is flowing in the wrong direction or to the wrong place.
Open-Heart Surgery: This is recommended for complex problems or disorders, closing holes, repairing of heart valves, widening the arteries to improve the blood flow or to close blood vessels. It is done by opening the chest and cutting the breastbone under general anesthesia. Holes are then stitched or closed by a patch.
Heart Transplant: Heart transplants are required if the defect cannot be treated by any other procedure and the diseased heart is replaced with the healthy heart which can be received from a donor.
What are the risks of the treating congenital heart defects?
The treatments like open-heart surgery and cardiac catheterizations can literally save lives but, there are certain risks involved, most common of which are infections. Catheter procedures, in particular, also come with the risk of damaging blood vessels.
Can congenital heart defects be prevented?
While it is not possible to ensure that a congenital heart defect is prevented altogether, the risks associated with their development can be minimized.
These include the following:
- Drinking alcohol or using illegal drugs should be avoided during pregnancy
- Blood sugar levels should be under control for those going through pregnancy
- The parent should be vaccinated for rubella or German measles or take measures to prevent being infected by them
- In the case of a family history of heart defects, genetic screening can be performed in advance to determine if the parent has a high change of producing offspring with a congenital heart defect
Coping and support for children with congenital heart defects
Congenital heart defects can affect and lead to other physical health problems when the patient has undergone surgery. To improve the lives of children born with the heart defects, it is vital to provide help and support to cope with the health issues and after effects of the disease and surgery on the life of the child.
Emotional and developmental problems: Due to prolonged recovery from surgery, the child may experience emotional and development problems and some may also have difficulty in learning, reading and writing.
Restrictions on physical activity: Certain types of exercises need to be limited or avoided altogether and the intensity of physical activity might also need to be controlled.
Prevention for infective endocarditis: This is an infection of the tissue lining the blood vessels and heart.