Ventricular Septal Defect (VSD): Symptoms, Causes and Treatment Options

Ventricular septal defect (VSD) is a condition in which a congenital hole is present in the wall separating the right and left ventricles located in the lower parts of the heart. This anatomical opening causes oxygenated blood to mix with deoxygenated blood.

Treatment involves closing this hole in the heart using special devices through a non-surgical angiographic (catheter) procedure or, when necessary, through a surgical operation, depending on the size and location of the hole.

Commonly known as a hole in the heart, this condition is among the most frequently encountered congenital heart diseases in childhood. Early diagnosis and intervention at the appropriate time are of great importance.

Thanks to modern medical technologies, permanent treatment of this cardiac problem can now be achieved with extremely high success rates. Thus, individuals who have completed their treatment can safely continue their lives with a healthy heart.

What Is the Structure of the Human Heart and How Does Ventricular Septal Defect (VSD) Affect the Heart?

The human heart is an organ consisting of four different chambers, with an extraordinary pumping system that works continuously throughout life. The two chambers in the upper part are called the atria, while the two more muscular and powerful chambers in the lower part are known as the ventricles. In a healthy circulatory system, deoxygenated blood returning from the body collects on the right side of the heart. Blood that has been enriched with oxygen in the lungs is located on the left side of the heart. To prevent these two different blood flows from mixing, there is a fairly thick and strong muscular wall between the right and left ventricles.

In ventricular septal defect (VSD), there is a structural opening, resembling a window, in the wall separating these two ventricles. This anatomical opening, one of the most common congenital heart abnormalities, may cause some of the oxygenated blood under high pressure in the left ventricle to pass through the hole and mix with the low-pressure deoxygenated blood in the right ventricle. This condition may increase the overall workload of the heart and cause changes in the amount of blood pumped to the lungs.

Why Might Ventricular Septal Defect (VSD) Not Cause a Problem During Fetal Development?

During their remarkable developmental process in the womb, babies obtain the oxygen they need not through their own lungs but directly through the umbilical cord connected to the mother. During this period, the baby’s lungs remain unexpanded because they have not yet filled with air, and the pressure in the pulmonary vessels is quite high. At this stage, the pressures between the right and left ventricles of the heart are almost balanced.

As a natural consequence of equal pressures on both sides, even if there is an opening in the wall between the ventricles, no significant blood flow occurs from one side to the other. Because blood tends to follow the path of least resistance, it continues along the heart’s normal pathways rather than passing through this hole. Thanks to this balance, the presence of such a structural abnormality in a baby in the womb generally does not negatively affect the baby’s development or the health of the heart muscle.

What Begins to Change in Ventricular Septal Defect (VSD) After Birth?

The moment of birth and the baby’s first breath completely rewrite the rules of the body’s circulatory system. When the baby cries and the lungs fill with air, the pulmonary vessels begin to expand, and resistance in these vessels rapidly decreases. At the same time, cutting the umbilical cord increases the body’s overall circulatory resistance. These changes cause the pressure on the left side of the heart to reach a much higher level than on the right side.

Immediately after this physiological adaptation process, high-pressure blood in the left ventricle begins to flow through the opening into the lower-pressure right ventricle. This passage of blood, called a shunt in medical terminology, means that oxygenated blood is sent back to the lungs. This additional blood volume reaching the lungs creates a new circulatory dynamic that requires the heart to work much harder.

To What Extent Can the Size of a Ventricular Septal Defect (VSD) Affect a Child’s Health?

The degree to which this anatomical opening in the heart may affect a child’s quality of life and health is generally closely related to the physical diameter of the opening and the response of the pulmonary vessels to this condition. In openings classified as small, the amount of blood passing from the left side to the right side remains quite limited, just as a large number of people cannot pass through a narrow doorway. As a result, the volume of blood flowing to the lungs remains at reasonable levels, and significant enlargement or signs of strain in the heart chambers are usually not observed.

In medium-sized openings, the situation begins to change somewhat. The amount of blood directed toward the lungs may increase to two or three times the amount flowing to the body. Because additional blood returns to the left atrium and left ventricle, these chambers may tend to enlarge slightly to accommodate the increased volume. The heart muscle may need to work harder than before to pump the blood required by the body.

Large openings have the potential to place much greater strain on the circulatory system. In these cases, pulmonary blood flow may reach up to four times the systemic blood flow. While the heart attempts to supply the body with blood, it simultaneously makes an intensive effort to manage this enormous flow toward the lungs. If this condition is not recognized and evaluated in time, it may accelerate the process of cardiac fatigue.

What Risks May Develop in the Lungs If a Large Ventricular Septal Defect (VSD) Is Left Untreated?

In the presence of a large opening, blood is continuously pumped into the lungs at high pressure and in quantities much greater than normal. Due to their thin and delicate structure, the pulmonary vessels may not tolerate this high pressure for a prolonged period. The body may develop a defense mechanism against this excessive pressure, gradually thickening the walls of the pulmonary vessels and narrowing their internal diameters.

This structural change may cause resistance in the pulmonary vessels to increase progressively. If the resistance exceeds a certain critical threshold and becomes higher than the general systemic resistance, the direction of blood flow may reverse. At this stage, deoxygenated blood begins to mix with oxygenated blood and is pumped into the body. This condition, called Eisenmenger syndrome, which manifests with symptoms such as bluish discoloration of the skin, may indicate serious difficulties in the circulatory system. Therefore, it is extremely important to bring the process under control and carry out appropriate evaluations long before it reaches this stage.

What Are the Types of Ventricular Septal Defect (VSD) and Where Do They Occur in the Heart?

The wall between the ventricles forms during embryological development through the joining and fusion of several different tissues. Disruptions in different regions of this complex fusion process cause openings to develop at different points in the heart. Classifying these openings according to their anatomical structures and locations is very important for treatment planning.

The main types of ventricular septal defect according to their anatomical locations are:

• Perimembranous
• Muscular
• Inlet
• Outlet

Among these types, the most commonly encountered in clinical practice are perimembranous openings located at the junction between the thin membranous portion of the wall and the muscular tissue. They are situated very close to the heart valves. Muscular types are located in the region of the heart composed entirely of thick muscular tissue and are surrounded by strong muscle fibers. Inlet types are located directly beneath the heart valves, while outlet types are positioned immediately below the valves of the main vessels that pump blood out of the heart.

Which Types of Ventricular Septal Defect (VSD) Have the Potential to Close Spontaneously?

The body’s mechanisms for repairing or compensating for anatomical abnormalities can sometimes work extremely effectively. In particular, the location of the opening and the structure of the surrounding tissue provide important clues about whether this closure process may occur naturally.

Muscular openings, meaning those located within muscle tissue, are the group with the highest tendency to close spontaneously during children’s growth. As the surrounding muscle fibers thicken with the baby’s development and gradually constrict the opening with each contraction of the heart, these types have a very high likelihood of closing on their own during early childhood.

In perimembranous openings, the neighboring heart valve tissue may gradually extend over the opening, acting like a patch and helping it close or become smaller. However, because inlet and outlet openings located very close to the valves do not have such protective tissue mechanisms around them, spontaneous closure is generally not expected.

What Symptoms Does Ventricular Septal Defect (VSD) Cause in Infants and Children?

The vast majority of children with small openings may not experience any noticeable complaints in their daily lives and may go through an extremely energetic and active growth period. However, when the opening is medium or large, the baby’s body may show various signs because the heart needs to work harder. Especially during infancy, breastfeeding or bottle-feeding requires considerable effort, so the earliest symptoms usually appear during feeding.

The main symptoms frequently observed in these babies include:

• Sweating
• Rapid breathing
• Getting tired quickly
• Loss of appetite
• Failure to gain weight
• Frequent infections

A baby whose heart consumes more energy than normal may become tired quickly while sucking and feel the need to stop feeding at frequent intervals. Due to the increased volume of blood flowing to the lungs, breathing may become slightly faster and shallower. The combination of all these factors may cause the baby to use the calories consumed for breathing and keeping the heart working rather than for gaining weight. This may appear as a degree of slowing in growth curves.

How Does the Diagnostic Process Proceed in a Patient Suspected of Having Ventricular Septal Defect (VSD)?

During routine health checkups in children, hearing the sound produced as blood passes through the narrow opening inside the heart, known as a heart murmur, while listening to the chest usually provides the first clue. When a murmur is heard or signs suggesting that the heart is working harder than necessary are observed, echocardiography, one of the most fundamental examination tools, is used.

Echocardiography is an ultrasound examination that uses sound waves to obtain moving images of the heart, involves no radiation, and is extremely comfortable for children. Thanks to special color mapping technologies, the location of the opening in the heart, its precise measurements in millimeters, and the pressure differences created by the blood passing through it can be evaluated in considerable detail. This detailed mapping provides extremely valuable data for planning the treatment steps to be taken later.

For Which Patients May a Decision to Treat Ventricular Septal Defect (VSD) Be Considered?

Each child’s heart structure has unique characteristics, just like a fingerprint. Therefore, when determining the treatment approach, the aim is to make personalized decisions based on the patient’s anatomical structure and the extent to which the circulatory system is affected, rather than following a standard method.

If echocardiography examinations reveal a significant increase in blood flow toward the lungs, if the left chambers of the heart have begun to enlarge due to this load, and if the baby experiences problems such as feeding difficulties or delayed growth, treating these openings is considered a strong option. From an anatomical perspective, muscular types surrounded by healthy tissue and perimembranous types located at a safe distance from the heart valve may be considered suitable candidates for non-surgical treatment methods thanks to advancing technologies.

How Is the Traditional Method Applied in Non-Surgical Ventricular Septal Defect (VSD) Treatment?

In the past, surgical methods involving opening the chest were preferred to repair holes in the heart, whereas today much more delicate and precise approaches have come to the forefront. In these procedures performed in specially equipped laboratories, vessels in the groin area are generally used as entry points. In the traditional angiographic approach, both the artery and vein in the groin may be used simultaneously.

Using catheters, which are extremely thin, flexible tubes, and very fine steerable wires, the instruments are gently advanced from the groin vessel toward the heart. A guidewire is passed through the opening in the heart. This wire may be directed from the heart into another vascular pathway and brought out from there to create a type of guiding rail system inside the body. Through this secure pathway, a wider sheath carrying the umbrella-like device that will close the opening is delivered to the heart. The discs on both sides of the device are opened sequentially, allowing the opening to be grasped from both sides.

How Is the Ventricular Septal Defect (VSD) Procedure Performed Using the Modern Arterial Approach?

Advances in interventional medical technology provide new techniques that allow procedures to be performed in a much simpler and smoother manner. One of these is a more modern approach that uses only the arterial route, eliminating the need to create an external rail system with a guidewire.

In this technique, the delivery system entering through the artery in the groin reaches the left ventricle directly through the aorta, the heart’s main artery, and then crosses the opening to perform the procedure. By minimizing contact with other valves or structural tissues inside the heart, the procedure may be completed in a shorter time. This may help protect the internal structures of the heart and aims to make the process much more comfortable. The same procedure can also be performed through the venous route.

What Are the Characteristics of Closure Devices Used for Ventricular Septal Defect (VSD)?

These specially designed devices used to close the opening are manufactured from a highly biocompatible material called nitinol, which is made from a nickel-titanium alloy. Nitinol is a type of smart metal with shape-memory properties. Thanks to this feature, the device can be compressed into a long, thin form and placed inside an extremely narrow delivery tube.

When the delivery tube reaches the target location inside the heart and releases the device, the device returns within seconds to its original, previously designed umbrella-like or plug-like shape, also with the help of body temperature. While devices with a thicker waist are preferred for openings within muscular tissue, more flexible new-generation devices with special funnel-shaped designs that do not exert pressure on surrounding tissues may be used for openings in the membranous portion or areas closer to the valves.

What Are the Differences Between Non-Surgical Ventricular Septal Defect (VSD) Treatment and Open Surgery?

Open-heart surgery, which requires stopping the heart and opening the chest, is a valuable method that has been safely performed for many years and has helped treat numerous patients. However, interventional methods are based on a very different philosophy in terms of how the procedure is carried out and its effects on the patient. This method aims to provide a solution by interfering as little as possible with the integrity of the body.

The potential advantages of the non-surgical method compared with open surgery include:

• No incision scar
• No need to stop the heart
• Rapid discharge
• Quick return to daily life
• Short procedure duration
• Reduced need for intensive care

The absence of a permanent scar in the chest area is an aesthetically reassuring factor for patients. The fact that the heart continues beating and does not need to be connected to an external pump contributes significantly to preserving the body’s overall physiological balance. Since a major incision in the heart muscle is generally not required, the heart’s recovery process may proceed much more quickly and comfortably.

How Does the Hospital Stay Proceed After Ventricular Septal Defect (VSD) Closure?

After the procedure is successfully completed, children leaving the angiography laboratory are generally taken directly to their own rooms rather than to the intensive care unit. In the room, the heart’s electrical activity continues to be monitored continuously and carefully through a monitor using soft pads placed on their chests.

To prevent bleeding at the small entry sites in the groin, children are asked to rest without bending their legs for the first few hours. The following morning, a detailed ECG recording of the heart’s electrical activity and an echocardiography examination are performed. Once it is confirmed that the device is positioned in the intended area and is compatible with the surrounding tissues, patients can safely return home on foot very shortly after the procedure, usually within approximately twenty-four hours.

What Should Patients with Ventricular Septal Defect (VSD) Pay Attention to After Discharge?

The integration of the metallic alloy device placed in the heart with the body’s natural tissues and its coverage by a thin membrane layer is a process that takes time. During this sensitive healing period, a mild blood-thinning treatment at the dosage recommended by the physician, generally covering the first six months, may be used to prevent clot formation on the device.

The recommended periods for routine echocardiography follow-up examinations after the procedure are:

• First month
• Third month
• Sixth month
• Twelfth month
• Annual intervals

Another important consideration during the first six months is the use of preventive antibiotics before dental treatments or potential surgical procedures to prevent bacteria from settling on the device (infective endocarditis prophylaxis). Once the device is completely covered by tissue, the need for such preventive measures generally disappears. These regular follow-ups are extremely beneficial for monitoring the heart’s adaptation to its new condition.

What Kind of Life Awaits Children Treated for Ventricular Septal Defect (VSD) in the Long Term?

Thanks to early diagnosis and interventions performed at the appropriate time, the burden on the circulatory system can be reduced before the heart muscle becomes excessively strained. Patients may have the opportunity to return to their education, school routines, and social activities very shortly after discharge. Only to protect the healing process of the device, avoiding specific sports involving possible hard impacts to the chest may be recommended during the first few months after the procedure.

Apart from this period, all the energetic activities of childhood, such as running, playing, and cycling, are generally permitted. Thanks to advances in medical technology and the heart’s remarkable capacity for healing, the aim is for these children to be able to run and play on equal terms with their friends in the years ahead and achieve an unrestricted, healthy quality of life. When the process is managed correctly, their hearts can be expected to continue beating much more strongly.