A ventricular septal defect is an opening in the ventricular septum, or dividing wall between the two lower chambers of the heart known as the right and left ventricles. VSD is a congenital (present at birth) heart defect. As the fetus is growing, something occurs to affect heart development during the first eight weeks of pregnancy, resulting in a VSD.
Normally, oxygen-poor (blue) blood returns to the right atrium from the body, travels to the right ventricle, then is pumped into the lungs where it receives oxygen. Oxygen-rich (red) blood returns to the left atrium from the lungs, passes into the left ventricle, and then is pumped out to the body through the aorta.
A ventricular septal defect allows oxygen-rich (red) blood to pass from the left ventricle, through the opening in the septum, and then mix with oxygen-poor (blue) blood in the right ventricle.
There are four basic types of VSD:
Ventricular septal defects are the most commonly occurring type of congenital heart defect, accounting for 25 percent of congenital heart disease cases.
The heart is forming during the first eight weeks of fetal development. It begins as a hollow tube, then partitions within the tube develop that eventually become the septa (or walls) dividing the right side of the heart from the left. Ventricular septal defects occur when the partitioning process does not occur completely, leaving an opening in the ventricular septum.
Some congenital heart defects may have a genetic link, either occurring due to a defect in a gene, a chromosome abnormality, or environmental exposure, causing heart problems to occur more often in certain families. Most ventricular septal defects occur sporadically (by chance), with no clear reason for their development.
If not treated, this heart defect can cause lung disease. When blood passes through the VSD from the left ventricle to the right ventricle, a larger volume of blood than normal must be handled by the right side of the heart. Extra blood then passes through the pulmonary artery into the lungs, causing higher pressure than normal in the blood vessels in the lungs.
A small opening in the ventricular septum allows a small amount of blood to pass through from the left ventricle to the right ventricle. A large opening allows more blood to pass through and mix with the normal blood flow in the right heart. Extra blood causes higher pressure in the blood vessels in the lungs. The larger the volume of blood that goes to the lungs, the higher the pressure.
The lungs are able to cope with this extra pressure for while, depending on exactly how high the pressure is. After a while, however, the blood vessels in the lungs become diseased by the extra pressure.
As pressure builds up in the lungs, the flow of blood from the left ventricle, through the VSD, into the right ventricle, and on to the lungs will diminish. This helps preserve the function of the lungs, but causes yet another problem. Blood flow within the heart goes from areas where the pressure is high to areas where the pressure is low. If a ventricular septal defect is not repaired, and lung disease begins to occur, pressure in the right side of the heart will eventually exceed pressure in the left. In this instance, it will be easier for oxygen-poor (blue) blood to flow from the right ventricle, through the VSD, into the left ventricle, and on to the body. When this happens, the body does not receive enough oxygen in the bloodstream to meet its needs.
Because blood is pumped at high pressure by the left ventricle through the VSD, tissue damage may eventually occur in the right ventricle. Bacteria in the bloodstream can easily infect this injured area, causing a serious illness known as bacterial endocarditis.
Some ventricular septal defects are found in combination with other heart defects (such as in transposition of the great arteries).
The size of the ventricular septal opening will affect the type of symptoms noted, the severity of symptoms, and the age at which they first occur. A VSD permits extra blood to pass from the left ventricle through to the right side of the heart, and the right ventricle and lungs become overworked as a result. The larger the opening, the greater the amount of blood that passes through and overloads the right ventricle and lungs.
Symptoms often occur in infancy. The following are the most common symptoms of VSD. However, each child may experience symptoms differently. Symptoms may include:
The symptoms of VSD may resemble other medical conditions or heart problems. Always consult your child's physician for a diagnosis.
Your child's physician may have heard a heart murmur during a physical examination, and referred your child to a pediatric cardiologist for a diagnosis. A heart murmur is simply a noise caused by the turbulence of blood flowing through the opening from the left side of the heart to the right.
A pediatric cardiologist specializes in the diagnosis and medical management of congenital heart defects, as well as heart problems that may develop later in childhood. The cardiologist will perform a physical examination, listening to the heart and lungs, and make other observations that help in the diagnosis. The location within the chest where the murmur is heard best, as well as the loudness and quality of the murmur (harsh, blowing, etc.) will give the cardiologist an initial idea of which heart problem your child may have. Diagnostic testing for congenital heart disease varies by the child's age, clinical condition, and institutional preferences. Some tests that may be recommended include the following:
Specific treatment for VSD will be determined by your child's physician based on:
Small ventricular septal defects may close spontaneously as your child grows. A larger VSD usually requires surgical repair. Regardless of the type, once a ventricular septal defect is diagnosed, your child's cardiologist will evaluate your child periodically to see whether it is closing on its own. A VSD will be repaired if it has not closed on its own— to prevent lung problems that will develop from long-time exposure to extra blood flow. Treatment may include:
In most cases, children will spend time in the intensive care unit (ICU) after a VSD repair. During the first several hours after surgery, your child will most likely be drowsy from the anesthesia that was used during the operation, and from medications given to relax him or her and to help with pain. As time goes by, your child will become more alert.
While your child is in the ICU, special equipment will be used to help him or her recover, and may include the following:
Your child may need other equipment not mentioned here to provide support while in the ICU, or afterwards. The hospital staff will explain all of the necessary equipment to you.
Your child will be kept as comfortable as possible with several different medications; some of which relieve pain, and some of which relieve anxiety. The staff may also ask for your input as to how best to soothe and comfort your child.
After discharge from the ICU, your child will recuperate on another hospital unit for a few days before going home. You will learn how to care for your child at home before your child is discharged. Your child may need to take medications for a while, and these will be explained to you. The staff will give you written instructions regarding medications, activity limitations, and follow-up appointments before your child is discharged.
Most infants and older children feel fairly comfortable when they go home. Pain medications, such as acetaminophen or ibuprofen, may be recommended to keep your child comfortable. Your child's physician will discuss pain control before your child is discharged from the hospital.
Often, infants who fed poorly prior to surgery have more energy after the recuperation period, and begin to eat better and gain weight faster.
After surgery, older children usually have a fair tolerance for activity. Your child may become tired quicker than before surgery, but usually will be allowed to play with supervision, while avoiding blows to the chest that might cause injury to the incision or breastbone. Within a few weeks, your child should be fully recovered and able to participate in normal activity.
You may receive additional instructions from your child's physicians and the hospital staff.
Most children who have had a ventricular septal defect repair will live healthy lives. Activity levels, appetite, and growth will return to normal in most children. Your child's cardiologist will recommend that antibiotics be given to prevent bacterial endocarditis for a specific time period after discharge from the hospital.
Outcomes also depend on the type of VSD, as well as how early in life the VSD was diagnosed and whether or not it was repaired. With early diagnosis and repair of a VSD, the outcome is generally excellent, and minimal follow-up is necessary. When a VSD is diagnosed later in life, if complications occur after surgical closure, or the VSD is never repaired, the outlook is generally poor. There is a risk for developing pulmonary hypertension (high blood pressure in the blood vessels of the lungs) or Eisenmenger syndrome. These individuals should receive follow-up care at a center that specializes in adult congenital heart disease.
Consult your child's physician regarding the specific outlook for your child.
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