Congenital heart disease

How is it caused?

Some of the known causes of the condition are:

• Genetic and chromosomal abnormalities as in Down’s syndrome and Turner’s syndrome.
  
• A family history of the condition exposes a person to an increased risk.
  
• Diseases affecting the mother during pregnancy, like rubella, diabetes, hypertension.
  
• Alcohol and drug abuse by the mother during pregnancy.
  
• Certain medications like thalidomide, used to treat seizure disorders in the mother may cause the condition in babies.
  
• Children born at high altitudes have a higher risk of being born with heart defects.

What are the symptoms?

The symptoms vary with the type of congenital abnormality that affects an individual. The common signs that may be noticed are breathlessness in the baby, a blue tinge to the skin or the lack of normal growth.

1. Atrial septal defect –  There may be no symptom of the condition and it may be detected during a routine check-up. It may also cause shortness of breath and changes in the heartbeat.
   
2. Ventricular septal defect – persons with this defect usually have frequent respiratory infections.
   
3. Pulmonary stenosis – because of narrowing of the blood vessel, the symptoms may include constant fatigue and shortness of breath. When this is present with other conditions (Fallot’s tetralogy), there may be other symptoms like bluish tinge to the child’s skin and weakness in the child especially noted after feeds and exercise.

How is CHD diagnosed?

Diagnosis of CHD is done mainly by a clinical examination when a murmur may be detected in the heart sounds. An ECG gives a clear picture of the rhythms of the heart. In conditions of enlargement of the chambers of the heart, a chest radiograph is done. Echocardiography is a procedure in which sounds of the heart are converted into frequencies, which help to monitor heart changes. To confirm the nature of the heart defect, a procedure called cardiac catheterisation that measures blood flow and pressures within different parts of the heart, is done.

What is the treatment?

Though some medication may be given in an emergency situation when the baby turns blue, long-term treatment is only achieved through surgery. An open-heart surgery is most often done to correct the defects. This form of surgery is a major operation and may involve many risks. Patients undergoing an open-heart surgery are at risk from the anaesthesia as well as from the surgery itself. Continuous monitoring of the heart needs to be done during and after the procedure.

Patients with high blood pressure should be more careful before going in for the surgery since extra care needs to be taken while administering the anaesthetic.

Can CHD be prevented?

Though CHD cannot be prevented, care can be taken to reduce the risks. Medications during pregnancy must be taken with utmost care. Regular check-ups for diseases like rubella must be done very early during pregnancy. Genetic counselling must be given to the parents in case of a family history of the condition.