Türkçe
Deutsch
العربية
Русский
Catheter-based patent ductus arteriosus (PDA) closure is the procedure of permanently closing the “ductus arteriosus” vessel that remains open congenitally in the heart by using special occluders advanced through thin catheters from the groin area, without opening the rib cage or requiring open heart surgery. Also known as nonsurgical treatment of a heart defect, this safe method enables patients to regain their health much more quickly, painlessly, and comfortably without experiencing major surgical trauma. Thanks to this intervention performed using advanced angiography technologies, the risk of infection is minimized, the hospital stay is limited to only a few hours, and the healthy functioning of the heart is rapidly restored.
What Is Life Like in the Womb and What Is Patent Ductus Arteriosus (PDA)?
The developmental process in the womb is a flawless marvel of engineering. During this period, babies’ lungs are not yet filled with air and remain completely collapsed. Because the lungs are collapsed, the resistance in their vessels is much higher than the resistance in all other vessels in the body. The developing baby’s oxygen needs are met directly through the placenta connected to the mother via the umbilical cord rather than through the lungs. Most of the blood pumped from the right side of the heart is directed straight to the body through a special bridging vessel located between the main pulmonary artery and the main systemic artery instead of going to the lungs, which are not yet functioning and have high resistance.
This vital bridging vessel, which plays an extremely critical role in the earliest stages of life, is called the ductus arteriosus. During this fetal circulation stage in the womb, approximately ninety percent of the blood pumped from the right ventricle passes through this vessel, allowing the placental oxygenation cycle to continue smoothly. Keeping this vessel open until birth is one of the most fundamental conditions for completely healthy development, ensuring that the body receives oxygen and the baby grows properly.
What Happens at Birth and How Does Patent Ductus Arteriosus (PDA) Close?
When the baby takes the first breath at birth, enormous physiological changes begin within seconds in the body emerging from the dark, fluid-filled environment of the womb. With that first strong breath, the collapsed air sacs of the lungs rapidly expand, and the lungs suddenly fill with oxygen. This causes a sudden and massive dilation of the pulmonary vessels, dramatically reducing vascular resistance in the lungs. At the same time, the general vascular resistance in the body increases when the umbilical cord is cut.
The sudden rise in the baby’s blood oxygen level and the rapid decrease of certain special hormones coming from the placenta send a very strong contraction signal to the specialized muscle cells in the wall of the ductus arteriosus. This physiological chain reaction causes the vessel wall to constrict rapidly, generally closing the vessel completely to blood flow within the first two or three days after birth. Over the following few weeks, the proliferation of cells within the vessel, fusion of the tissues, and formation of connective tissue cause this bridge to dry out completely and transform into a thin remnant of connective tissue. The heart’s normal circulatory anatomy thus reaches its final healthy form.
How Does Patent Ductus Arteriosus (PDA) Harm the Body If Closure Does Not Occur?
Disruption of this highly organized and programmed closure process due to various anatomical causes, genetic factors, premature birth, or external factors such as oxygen deprivation results in the ductus remaining open. Because pulmonary pressure falls to normal levels after birth while systemic blood pressure rises, blood continuously flows from the high-pressure area toward the low-pressure area. This leakage continues without interruption every time the heart contracts and relaxes.
If the opening is very small, the heart may tolerate the condition for a long time without producing any symptoms. However, in moderate and large openings, excessive blood is pumped into the lungs with every heartbeat, and this blood returns to the left side of the heart, creating a significant volume overload. To pump this constantly increasing extra blood load, the left side of the heart gradually stretches and enlarges like an elastic band. Although this is initially a physical compensation mechanism, over time the heart muscle becomes extremely fatigued, and irreversible heart failure develops. At the same time, the continuous impact of high-pressure blood on the pulmonary vessels over many years causes permanent stiffening and structural deterioration in those vessels, creating the conditions for pulmonary blood pressure to rise to very high levels.
What Are the Symptoms of Patent Ductus Arteriosus (PDA) in Infants and Children?
The symptoms caused by the open vessel vary greatly according to the size of the opening and the patient’s physical capacity.
The main symptoms families should pay close attention to include:
- Easy fatigue
- Rapid breathing
- Failure to gain weight
- Excessive sweating
- Frequent lung infections
- Inability to sleep at night and frequent waking
The reason these findings develop is entirely mechanical. Because the heart and lungs are constantly burdened by excess fluid, the child becomes short of breath during physical effort and even while feeding. Feeding itself is a serious form of exercise, especially for infants. While sucking milk, the breathing rate increases so much that the infant cannot tolerate the effort and stops feeding halfway through. Since the body is constantly working at high speed, metabolism accelerates, leading to excessive sweating and interrupted weight gain because the calories consumed are spent merely on breathing. In addition, continuously wet and edematous lung tissue creates an ideal environment for bacteria and viruses to reproduce, forcing these children to visit the hospital repeatedly with conditions such as bronchitis or pneumonia.
Which Methods Are Used to Diagnose the Disease and How Does Patent Ductus Arteriosus (PDA) Appear?
During the physical examination, a heart murmur heard while listening to the chest that resembles a continuously operating machine is the first and most important step in diagnosis. However, the definitive diagnosis is made with echocardiography, or ultrasound of the heart, which shows the size and function of the heart. This method is completely painless, does not involve radiation, and displays the internal structure of the heart on monitors within seconds.
With color mapping created using special sound waves, the direction and speed of the leaking blood can be clearly observed. Echocardiography devices not only measure the diameter of the opening but also calculate, with millimetric precision, how much the left atrium and left ventricle have been affected by the leakage and how far they have stretched. During procedure planning, other congenital abnormalities that may be present in the heart are also fully screened and evaluated during this detailed examination.
In Which Situations Is Catheter-Based Patent Ductus Arteriosus (PDA) Closure Necessary?
The angiographic method, which eliminates the physical and emotional trauma caused by open heart surgery, is essential for protecting the patient’s future quality of life when certain medical criteria are met. The fact that a patient has no symptoms at the time does not mean that the vessel will remain harmless throughout life.
The main conditions requiring intervention include:
- Heart enlargement
- Developmental delay
- Dependence on a ventilator
- Risk of infection of the heart lining
The procedure is required in every child whose heart has begun to show significant stretching and enlargement in order to prevent future heart failure. Intervention should not be delayed in children with reduced exercise capacity or failure to gain weight. In very low-birth-weight infants struggling to survive in intensive care units, this procedure plays a life-saving role by relieving fluid overload in the lungs and helping them come off the ventilator. In addition, even with very small openings, closure is often preferred as a preventive measure because rapidly flowing blood may damage the vessel wall and allow bacteria to settle there, creating a serious risk of infection.
In Which Patients Can Catheter-Based Patent Ductus Arteriosus (PDA) Closure Not Be Performed?
There are very exceptional and critical situations in which even this highly safe procedure cannot be performed. The most important obstacle is advanced disease caused by large openings that have remained untreated for years, leading to irreversible stiffening of the pulmonary vessels.
In this condition, pulmonary vascular resistance exceeds systemic resistance, blood flow reverses from right to left, and the patient develops bluish discoloration of the lips and fingertips. At this stage, the open vessel in the heart is no longer the cause of the disease but instead functions as a safety valve that relieves the overloaded right side of the heart. If this pressure-release pathway is mechanically closed, the heart cannot withstand the accumulated high pressure, and sudden failure develops. In addition, if the patient has an active microbial infection or an unresolved blood-clotting disorder, it is considered unsafe to perform the procedure until these conditions have been completely treated.
How Does the Physical Shape of the Vessel Affect the Strategy for Catheter-Based Patent Ductus Arteriosus (PDA) Closure?
Just as human faces differ from one person to another, the internal structures, curves, and flexibility of these open vessels also vary greatly among patients. To select the correct medical device, a three-dimensional map of the vessel is created at the most critical stage of the procedure.
Cone-shaped vessels are wide on one side and narrow like a funnel on the other. They are the most commonly encountered form today and the easiest to close with occluders. Window-shaped vessels consist of only a short opening between two very large arteries and require much more careful sizing because there is little area for the device to anchor. Sometimes long, straight tubular structures are encountered, while at other times complex sac-like anatomies with multiple constrictions may be present. Bioengineered closure devices with different levels of flexibility and sizes have been designed for each shape. The success of the procedure depends entirely on accurate analysis of these anatomical forms.
Which Technologies Are Used in Catheter-Based Patent Ductus Arteriosus (PDA) Closure?
The level reached by modern medical technology is comparable to what is seen in science fiction films. The primary material used in these procedures is a special alloy created by combining titanium and nickel in a precise ratio. The most extraordinary capability of this alloy is a feature called “shape memory.” Outside the body, the devices can be straightened like a thread and compressed into very thin tubes, but as soon as they come into contact with body temperature, they return within seconds to the umbrella shape programmed during manufacturing.
The most commonly used medical device designs include:
- Asymmetrical umbrellas
- Double-sided symmetrical discs
- Miniature plugs
- Coiled wires
Asymmetrical devices resembling a mushroom at one end and an umbrella at the other fit particularly well inside cone-shaped vessels and completely block the opening within seconds by promoting blood clotting through special fabrics incorporated into them. Hinged devices with equal width on both sides provide high mobility in highly curved vessels. Special coiled wires are mainly preferred for closing thread-like openings by creating a mesh. However, their use has now almost completely disappeared. Each device is selected a few millimeters larger than the patient’s vessel diameter to ensure that it firmly anchors to the tissues. Your physician will choose the device according to angiographic and echocardiographic measurements.
How Is Catheter-Based Patent Ductus Arteriosus (PDA) Closure Performed Step by Step in the Angiography Room?
This intervention consists of a series of precise steps carefully performed under local or general anesthesia according to the patient’s age and psychological condition in highly sterile angiography laboratories that minimize the risk of infection. The procedure is conducted entirely through microcatheter systems advanced inside the blood vessels without making any incision in the rib cage.
The process generally begins with locating the vessels in the right groin under ultrasound guidance and placing thin sheaths through entry points as small as a needle tip. Guidewires and soft-tipped catheters passed through these sheaths are gently advanced toward the heart by following the natural direction of blood flow. Once the internal chambers of the heart are reached, current pressures are measured, and the exact location and dimensions of the opening are determined using X-ray devices and special contrast agents.
After the measurements are completed, the selected shape-memory device is attached to the end of a long delivery wire with a screw mechanism and advanced through a very thin tube to the target area. Under X-ray guidance, the device is positioned precisely in the center of the vessel opening and slowly pushed out of the tube so that it can regain its original shape. Both sides of the device compress the vessel like a sandwich and close it completely. After final checks confirm that the device is not damaging the surrounding tissues, the external screw mechanism is rotated to release the device. All wires are withdrawn, and the millimetric opening in the groin is closed with a bandage to complete the procedure.
Why Is Catheter-Based Patent Ductus Arteriosus (PDA) Closure Vital in Premature Infants?
Premature infants weighing only a few hundred grams and struggling to survive in pediatric intensive care units represent the most fragile period of human physiology. In these infants, an open vessel in the heart floods the already very weak lungs with fluid and makes it impossible for the baby to be separated from mechanical ventilation. In previous years, the chests of these tiny infants had to be surgically opened and the vessel tied with sutures. However, these traumatic operations carried risks such as bleeding, nerve damage, and permanent curvature of the spine.
Today, this situation has completely changed thanks to specially developed occluders smaller than a pea. The vessels in these infants are so thin that touching the arteries may impair blood circulation to the legs. Therefore, the procedure is performed entirely through the veins under careful ultrasound guidance within only a few minutes. Freed from the destructive burden of surgery, these infants may be separated from the ventilator shortly after device placement, begin breathing independently, and start gaining weight rapidly.
The most important point to remember is that transcatheter procedures performed in premature infants may be highly dangerous. It must not be forgotten that surgical treatment always remains an important option. Ideally, the treatment plan for these patients should be determined jointly by a surgeon, neonatologist, and cardiologist.
Is Catheter-Based Patent Ductus Arteriosus (PDA) Closure Possible in Adults?
These openings, which may go unnoticed or be overlooked during childhood because they cause no symptoms, can emerge in adulthood with symptoms such as shortness of breath and palpitations as pulmonary resistance gradually increases. However, the passing decades may cause significant physical damage to the vessel structure. Calcification begins in the vessel wall, and the vessel may become dilated and develop sac-like deformities.
Because the tissues lose elasticity in adults, much larger devices must be selected. In addition, this opening may occur simultaneously with other congenital problems, such as narrowing of the main artery that distributes blood to the body. In modern angiography laboratories, both problems can be treated during the same session. Covered stents are placed in the narrowed areas, both widening the diameter of the main vessel and completely closing the open ductus arteriosus with the covering over the stent, thereby providing a dual benefit.
Does Catheter-Based Patent Ductus Arteriosus (PDA) Closure Carry Risks Like Every Medical Intervention?
Although this method is exceptionally safe and comfortable compared with surgical procedures, every invasive intervention performed on the human body naturally carries certain potential risks. Specialist teams are highly equipped to anticipate and immediately manage these situations.
Some possible undesirable events include:
- Device displacement
- Narrowing of surrounding vessels
- Minor blood leakage
- Bruising in the groin
It is rare for the selected device to fail to withstand the pressure and move or become displaced. If this occurs, the device can be captured and retrieved within seconds on the angiography table using special snare-shaped wires, and a new device of a more appropriate size can be placed. Sometimes the large discs of the device may exert slight pressure on the pulmonary or cardiac vessels. If this is detected during the procedure, the device is immediately replaced with a smaller model. Very slight blood leakage through the device may occur during the first few days, but cells rapidly fill these gaps with clots and naturally stop the leakage completely. Mild bruising in the groin area resolves spontaneously within a few days.
What Are Hospital Discharge and Recovery Like After Catheter-Based Patent Ductus Arteriosus (PDA) Closure?
The speed of recovery after the intervention is truly remarkable. Because the procedure is performed entirely through the blood vessels, there are no open wounds, sutures, or rib pain. Most patients can stand and return to their routine lives and homes within twenty-four hours after the procedure. Once the enormous extra blood load accumulated in the heart chambers is immediately eliminated, the fatigued heart muscle enters a rapid recovery process, and the enlarged chambers return to their former healthy dimensions within a few months.
The most critical issue during the following months is the time required for the surface of the metal-alloy device to become completely covered by the body’s own inner lining. During this period, the device may provide a surface on which bacteria circulating in the blood can attach. Therefore, during the first six months after the procedure, preventive antibiotics must be used before tooth extraction or any bleeding procedure to prevent bacteria from entering the bloodstream. Once the device has been covered by tissue, the patient can exercise and continue life freely, just like a healthy individual with no heart problem.
Frequently Asked Questions
Prof. Dr. İbrahim Cansaran Tanıdır is an internationally recognized specialist with nearly 20 years of clinical, academic, and interventional experience in the fields of congenital heart diseases, pediatric interventional cardiology, hybrid procedures, and radiation-reduced / fluoroscopy-free catheterization techniques.
To date, he has performed more than 10,000 pediatric cardiac catheterization procedures both in Turkey and abroad, and has pioneered advanced interventional and hybrid applications in complex structural heart diseases in our country.
His academic productivity represents a scientifically strong authority with 110 SCI/SCIE publications, 1,440 citations, and an H-index of 18 (Google Scholar, 2025).
