Brief overview
- What is a VSD? Congenital heart defect in which there is at least one hole between the right and left ventricles.
- Treatment: closure of the hole by open-heart surgery or cardiac catheterization. Medications are used only temporarily and are not suitable as permanent therapy.
- Symptoms: Small holes rarely cause symptoms, larger defects cause breathing problems, weakness in drinking, low weight gain, heart failure, pulmonary hypertension.
- Causes: Malformation during embryonic development, very rarely acquired through injury or heart attack.
- Risk factors: Alteration of the genetic material, diabetes during pregnancy
- Diagnosis: Typical symptoms, cardiac ultrasound, if necessary ECG, X-ray, CT, MRI
- Prevention: VSD is usually congenital, so there are no measures to prevent the hole in the heart.
What is a ventricular septal defect?
Classification of ventricular septal defects
If there is only a single hole, doctors refer to it as a “singular VSD”; somewhat more rarely, there are multiple defects in the ventricular septum. Doctors refer to these as “multiple ventricular septal defects.”
An “isolated VSD” is when the hole is the only malformation in the newborn. In other cases, the hole in the heart occurs in conjunction with other conditions. These include heart malformations such as tetralogy of Fallot (malformation of the heart), transposition of the great arteries (the aorta and pulmonary artery are reversed), or a univentricular heart (heart consists of only one ventricle).
It is not uncommon for a VSD to occur in association with syndromes such as trisomy 13, trisomy 18, or trisomy 21 (colloquially known as Down syndrome).
- Membranous VSD: Holes in the connective tissue part of the septum are rather rare (5 percent of all VSD), but tend to be large.
- Perimembranous VSD: In a perimembranous VSD, the defect is located at the junction between connective tissue and muscle. Seventy-five percent of all VSDs are located in the muscular portion, but usually extend to the membranous portion and are therefore referred to as “perimembranous.”
- Muscular VSD: Purely muscular VSD are rather rare with 10 percent, often there are several small defects.
Frequency
At 40 percent, ventricular septal defect is the most common congenital heart defect. It occurs in about five out of every 1,000 newborns, with girls being affected slightly more often. The ratio of boys to girls affected is about 1:1.3.
Normal blood circulation
The deoxygenated blood enters the right atrium from the systemic circulation via the superior and inferior vena cava and is pumped from there to the pulmonary arteries via the right ventricle. In the lungs, the blood is oxygenated and flows back to the left atrium via the pulmonary veins. The left ventricle pumps the oxygenated blood into the systemic circulation via the aorta.
Change in ventricular septal defect
When does a VSD require surgery?
Whether and how a ventricular septal defect is treated depends on how large the hole is, what shape it is, and exactly where it is located.
A small hole usually causes no discomfort and requires no treatment. It is also possible that the hole will shrink over time or close on its own. This is the case in about half of the patients: In them, the VSD closes within the first year of life.
Medium-sized, large and very large holes are operated on in all cases. Depending on the individual case, there are different surgical methods to close the hole.
Open heart surgery
The physician first opens the chest and then the right atrium. The defect in the septum of the heart is visible through the atrioventricular valve (tricuspid valve). The physician then closes the hole with the patient’s own tissue from the pericardium or with a plastic platelet (patch). The heart covers the material with its own tissue in a short time. There is no risk of rejection with this method. The operation is now considered routine and carries only minor risks. Patients in whom the hole in the heart has been closed are then considered cured.
Cardiac catheterization
Another option for closing the ventricular septal defect is the so-called “interventional closure”. In this case, the heart is not accessed via surgery, but rather via a catheter that is advanced into the heart via the inguinal vein. The physician positions an “umbrella” over the catheter in the area of the defect and uses it to close the hole.
It is not possible to treat a ventricular septal defect with medication. In some cases, however, VSD patients receive medication to stabilize them until surgery. This is the case, for example, when infants or children are already showing symptoms or are too weak for immediate surgery.
The following medications are used:
- Blood pressure-lowering drugs such as beta-blockers, dehydrating drugs (diuretics) and so-called aldosterone receptor antagonists if there are signs of heart failure.
- If weight gain is too low, those affected are given a special diet with lots of calories.
Some patients continue to receive medication for several weeks after surgical closure of the hole to relieve pressure on the heart and lungs.
Symptoms
Symptoms of a VSD depend on how large the hole in the heart’s septum is.
Symptoms of small VSD
Symptoms of medium and large VSD
Medium and large holes in the septum damage both the heart and the pulmonary arteries over time. As the heart has to pump more blood through it, it becomes increasingly overloaded. As a result, the heart chambers enlarge and heart failure develops.
Typical symptoms are:
- Shortness of breath, rapid breathing and shortness of breath
- Weakness to drink: babies are too weak to drink enough.
- Lack of weight gain, failure to thrive
- Increased sweating
- Lower respiratory tract more susceptible to infections
It is not always possible to operate immediately on affected babies because of their weakness. Until then, temporary treatment with medications may be necessary.
Symptoms of Very Large Ventricular Septal Defects
Finally, it is possible that the direction of blood flow is reversed: oxygen-poor blood enters the bloodstream, and the organism is no longer supplied with sufficient oxygen. This lack of oxygen is visible as a blue discoloration of the skin (cyanosis). Doctors speak of the so-called “Eisenmenger reaction” in connection with a VSD. Patients who have already developed this condition have a significantly reduced life expectancy.
It is especially important to operate on patients with very large defects in infancy or childhood before changes in the pulmonary vessels occur!
Causes and risk factors
Causes of a “hole in the heart
Secondary VSD: In secondary ventricular septal defect, newborns are born with a completely closed septum. The hole in the septum develops later, for example, due to an injury, an accident, or heart disease (myocardial infarction). Secondary (acquired) VSDs are extremely rare.
Risk factors for a “hole in the heart
Changes in genetic makeup: Sometimes ventricular septal defects occur in combination with other genetic conditions. These include, for example, certain chromosomal defects such as trisomy 13, trisomy 18 and trisomy 21. In addition, there is a known familial clustering of VSD: It occurs in clusters when parents or siblings have a congenital heart defect. Thus, the risk is increased threefold if a sibling has a VSD.
Disease of the mother during pregnancy: Children of mothers who develop diabetes mellitus during pregnancy have an increased risk of VSD.
Before birth
Major defects in the septum may be detected before birth.
If the child is in a favorable position, this is possible during targeted examinations (such as the “malformation ultrasound” between the 19th and 22nd week of pregnancy). If such a defect is detected, further examinations follow to see how the defect develops.
Important to know: It is possible for the hole in the heart to close again while still in the womb. According to the latest findings, this is the case in up to 15 percent of all affected children.
After birth
Newborn examination
Cardiac ultrasound
If a VSD is suspected, the cardiologist performs an ultrasound examination of the heart. This usually provides good evidence of a hole in the heart. The doctor assesses the location, size and structure of the defect. The examination takes only a short time and is painless for the baby.
Further examinations
In some cases, the doctor performs other tests to get more detailed information about the defect in the septum. These include electrocardiogram (ECG) and X-ray examination, and less frequently computed tomography (CT) or magnetic resonance imaging (MRI).
Course of the disease and prognosis
Even patients with larger defects have a normal life expectancy if they are treated in time and the hole is successfully closed. Both the heart and the lungs are subsequently able to withstand normal stress.
In very large defects, the prognosis depends on whether the hole in the heart is discovered and treated early. If left untreated, heart failure (cardiac insufficiency) and high pressure in the pulmonary arteries (pulmonary hypertension) develop. These diseases generally shorten life expectancy: without treatment, affected individuals often die in young adulthood. However, if they are treated before corresponding diseases develop, they have a normal life expectancy.
Aftercare
Prevention
In most cases, a ventricular septal defect is congenital. Therefore, there are no measures to prevent the hole in the heart.