Ventricular septal defect (VSD) refers to a hole in the septum of the heart. About one-third of all congenital heart defects are ventricular septal defects. This makes VSD the most common congenital heart defect.
What is a ventricular septal defect?
Ventricular septal defect is a congenital (congenital) heart malformation. Thus, VSD is one of the cardiac defects. The cardiac septum between the two ventricles has a hole so that the right and left ventricles are connected. The symptoms depend on the size of the defect. Smaller defects often close on their own within the first two years of life. Larger defects may require surgery.
Causes
The causes of ventricular septal defect are unknown. There is a defect in the septum of the heart (ventricular septum). The defect can be located in a variety of places. Most commonly, it is found just below the aortic valve. Less commonly, muscular or perimembranous defects are present. Blood from the left heart is pumped into the systemic circulation, while blood from the right heart enters the lungs. Since the blood pressure in the pulmonary circulation is much lower than in the other vessels of the body, the left heart must pump at a greater pressure. Thus, there is also greater pressure in the left ventricle than in the right ventricle. Oxygen-rich blood thus passes from the left to the right ventricle via the ventricular septal defect. A so-called left-right shunt is present. Therefore, VSD also belongs to the shunt vitias.
Symptoms, complaints, and signs
The consequences of this shunt depend on the size of the VSD. If the defect is small, there will be few symptoms. Many of these defects are discovered only by chance. However, in medium-sized and large ventricular septal defects, much of the arterial blood flows back into the right heart. This then pumps the blood back to the lungs. The additional blood volumes increase the blood pressure in the vessels of the lungs. Pulmonary hypertension develops. The right heart has to pump against this increased blood pressure and therefore enlarges. This enlargement is called right heart hypertrophy. The vessels of the lungs cannot cope with the great pressure, so they harden over time. However, these hardenings only make the situation worse. Blood pressure in the lungs continues to rise and the right heart enlarges. At some point, the right heart pumps so vigorously that a shunt reversal occurs. From then on, blood flows through the ventricular septal defect from the right ventricle to the left ventricle rather than from the left ventricle to the right ventricle. The blood from the right ventricle comes from the systemic circulation and is low in oxygen. The body is therefore supplied with oxygen-poor blood. As a result, the patient’s skin takes on a slight blue color. The congestion of blood in the lungs can also cause pulmonary edema. In pulmonary edema, fluid collects in the alveoli. The consequences are shortness of breath and coughing. Children with a VSD often show increased breathing. They do not drink well and grow sparsely. Children with a VSD are often very thin.
Diagnosis and course of the disease
On auscultation of the heart, a press jet murmur may be heard over the third to fourth intercostal space. However, as the size of the ventricular septal defect increases, this murmur becomes quieter. If the defect is large, a diastolic flow murmur may occur as a result of the increase in blood pressure in the pulmonary circulation. The second heart sound is then split. The ECG is usually unremarkable in small defects. In a larger ventricular septal defect, signs of left ventricular hypertrophy or right ventricular hypertrophy are seen. Chest radiographs are unremarkable in small defects. Otherwise, signs of pulmonary edema are seen. Echocardiography is used to confirm the diagnosis. In older patients, cardiac catheterization is also performed to clarify the resistance conditions within the lungs.
Complications
Because ventricular septal defect is a heart defect, it primarily has a very negative effect on the life expectancy of the affected person and can reduce it. However, this usually only occurs if the condition is not treated. The affected person primarily suffers from very high blood pressure, so that a heart attack can occur.Permanent fatigue or exhaustion can also occur and have a very negative effect on the quality of life of the affected person. Ventricular septal defect does not heal itself and the symptoms worsen over time. Since the body does not receive an ordinary supply of oxygen, the affected person is also unable to engage in sports or strenuous activities. Especially in children, this can lead to delayed or very limited development. Many patients also suffer from severe shortness of breath or coughing. This condition is treated with the help of medication and by surgical intervention. In most cases, this can relieve the symptoms. However, those affected are dependent on regular examinations by a doctor in their lives to prevent further complications.
When should you see a doctor?
In the case of a ventricular septal defect, the patient is dependent on treatment by a physician. Since this is a serious complaint of the heart, a doctor should be consulted even at the first symptoms and signs of the disease to avoid further complications or, in the worst case, death of the affected person. As a rule, in the case of ventricular septal defect, a doctor should be consulted if the heart beats very strongly even during low exertion. During high exertion or during sporting activities, the affected persons themselves usually notice the high pulse and thus also the high heartbeat. Many patients also suffer from shortness of breath or a strong cough. If these symptoms occur over a longer period of time and do not disappear again on their own, an examination and treatment by a physician is necessary in any case. The disease can be examined and treated by a cardiologist. Since it is a hereditary disease, genetic counseling should be performed if the patient wishes to have children in order to prevent the recurrence of the disease. Whether this will result in decreased life expectancy cannot be universally predicted.
Treatment and therapy
In one-third of all infants with a VSD, the defect closes on its own within the first two years of life. In 20 percent of all infants, it at least shrinks. Larger defects are fatal in one tenth of affected infants within the first year of life. The children die from recurrent bronchial and lung infections or from acute left heart failure. Because patients with major ventricular septal defects often suffer from failure to thrive, they frequently require surgery in infancy. Otherwise, we actually wait to see if the defect will not close on its own. The VSD can be operated on using three different procedures:
- In the transatrial method, access is through the right atrium of the heart.
- Transventricular access is through the right ventricle of the heart
- And in the transarterial method, the access route is through the pulmonary artery or the aorta.
The defect is then closed with either a suture or a patch. Normally, a suture is avoided because the resulting scar can cause cardiac arrhythmias later. During the operation, patients are connected to the heart-lung machine. In uncomplicated ventricular septal defect, one percent of children die. Mortality is significantly higher in infants with heart failure. Complications occur in three to five percent of cases. The most serious complication is conduction disturbance. This is when the electrical excitation responsible for contraction of the heart muscle is not transmitted from the atrium to the ventricle.
Prevention
Ventricular septal defect is difficult to prevent. However, alcohol and smoking are major risk factors for maldevelopment of the unborn baby and should be avoided at all costs.
Follow-up
If the ventricular septal defect has been surgically closed, follow-up care is required. This initially takes place in the intensive care unit of the hospital. During this process, the patient is carefully monitored. Because there is a catheter on one leg, it must not be moved independently at first. In addition, intensive physical exertion must be avoided during the first week after the operation.During the patient’s stay in the hospital and before discharge, the position of the occluder is checked, usually by transesophageal echocardiography (TEE). This procedure can be used to determine whether the attached occluder is properly seated and whether the defect has also been correctly closed. In some patients, there is a risk of blood clots forming on the occluder. These can be detected with the aid of the TEE examination. If a clot is present, it is usually successfully dissolved by the administration of appropriate medication. To prevent further clots from forming, the patient takes medications such as clopidogrel and aspirin for three to six months. After three to six months, there is another check-up. Usually, no further medications to prevent a blood clot need to be administered at that time. Other medications the patient receives during follow-up treatment of ventricular septal defect are antibiotics. Their purpose is to prevent cardiovascular infections. If there are any possible abnormalities, a physician should be informed immediately.
Here’s what you can do yourself
A small ventricular septal defect may close spontaneously after birth. The most important self-help measure is for parents to carefully monitor the child and work closely with a cardiologist. Larger defects must be closed surgically. After surgery, the child requires bed rest and sparing. Parents must consult with the pediatrician and follow his or her instructions. In most cases, it is also necessary to adjust the child’s diet. Weight loss must be compensated for by giving fiber-rich drinks. If necessary, the child will need special supplements. In general, the child should be kept adequately hydrated. Children with a ventricular septal defect must not exert themselves. Rest is especially important in the first days and weeks after heart surgery. Gentle exercise is allowed afterwards in consultation with the doctor. The measures to be taken in the case of a ventricular septal defect depend on the size of the defect and the method of treatment. The pediatrician will specify appropriate measures and assist the child’s parents during treatment and follow-up. Endocarditis prophylaxis usually must be followed for 12 to 16 months.
