Approximately 8 out of 1000 newborns have some heart defect. This congenital mana may be insignificant, and it is not necessary to treat it and is not life-threatening. Another extreme is a severe cardiac disorder due to which, despite treatment, a newborn may die.
Development of heart defect
The heart of a fetus is beginning to develop in early pregnancy and is completely developed until the third month. An eventual abnormality of development in this vital period will result in congenital heart defect, and perhaps even more than one.
Abnormality can occur if a pregnant woman has rubella or other contagious disease in early pregnancy or if the child has defective chromosomes (see, for example, Down syndrome).
Some medications that a woman takes in early pregnancy may also cause heart abnormalities. Therefore, a woman who is pregnant or thinks she is pregnant should never take any medicines without the permission of a physician who knows about her condition. There is little tendency to inherit heart defect. If one of the parents has congenital heart defect, in 4% of cases the child will have the same or similar disorder.
In such cases, you should consult a genetic counselor before you decide to have a baby. But, since a parent with a heart defect has survived, a child should not be seriously affected by the disease. In most of congenital heart defects the cause is unknown.
In many cases of congenital heart defects there are no symptoms, and abnormalities are revealed only at a regular heart examination. On the other hand, in some cases the symptoms are pronounced. Sometimes they occur at birth, and sometimes at a childhood or much later. The symptoms are not directly related to the treatment. Many cases of heart defects without symptoms should be treated surgically in order to prevent the illness in later life.
The common symptoms is bluish discolouration (cyanosis). It occurs when an abnormal excess of deoxygenated blood circulates through the system. Mild cardiac decompensation in infants is seen as a difficulty in feeding, so the weight of the baby is below normal and it cries at shorter intervals. In infants with strong cardiac decompensation, these symptoms are more pronounced; breathing is accelerated and very difficult. An infant will almost certainly have cyanosis or cardiac decompensation.
Children with congenital heart defect can be out of breath during some physical activity and their physical development is usually weak. If they have cardiac decompensation, they can be out of breath even when they are resting.
A diagnose of heart defect is usually set by a stethoscope examination. With a perfectly healthy heart, the stethoscope catches the sound of shrinkage of the ventricle and closing of the heart valves. Most of the other sounds are called heart murmurs, although the presence of the other sound(s) does not have to mean that a person has a heart defect or that the heart is severely affected. For example, heart murmur can be heard if a blood flow in infant has increased significantly due to anemia. The physician can usually determine which sounds are signs of an abnormality, and which are not. Each abnormality generally generates a particular kind of murmur – for example, in case of pulmonary stenosis when the blood has to pass through the narrowed canal. In most cases the physician can diagnose the presence of abnormalities.
Have children with a completely healthy have heart murmurs. Such children should be treated the same way as any healthy person.
Special diagnostic findings
As soon as a doctor discovers a heart defect, further examinations are performed at the hospital. X-ray of the chest shows anomalies in the size and shape of the heart chambers. Electrocardiography captures the electrical impulses generated by heartbeats, thereby detecting possible enlargement of the heart chambers. In addition, ultrasound examination may be performed to detect the relative thickness of the heart chambers and the condition of the heart valves. These procedures are not painful, and no anesthesia is required.
In some cases, cardiac catheterization is required. A baby or a small child gets anesthesia or sedation, and the tube, called a catheter, runs through the blood vessel (usually in the leg) to the heart. The X-ray screen follows the passage of the catheter into the heart chambers through various openings. The catheter also provides pressure, oxygen and blood measurements in each of the heart chambers. Through the catheter, a contrast agent is injected in the blood vessels, the heart and the lungs, and the X-ray is recorded. The images show the shape and size of the heart chambers and valves. After these tests a heart specialist can diagnose the illness and decide on the best treatment.
A surgery is needed in most cases to correct the defect. If the disorder is not so difficult to require a momentary surgery, the surgical procedure is delayed until early childhood when the rate of success of the operation is much higher than in the infant age. With modern surgical methods, the success of most heart surgeries is nowadays very high and, after the surgery, children can hope to live a normal life. Cardiac failure in infants is treated with various drugs that may need to be given for several years until it is the time for surgery.