ASD Device Closure

Introduction

If you or your child has been diagnosed with an atrial septal defect (ASD) — a hole in the wall between the two upper chambers of the heart — you have probably already had an echocardiogram and a conversation with a cardiologist about closing it. This article is for the next part of that journey: understanding what ASD device closure involves, how it compares with surgical closure, what preparation looks like, what happens in the catheterisation lab, and what to expect during recovery.

ASD device closure is a catheter-based (also called transcatheter) procedure. Instead of opening the chest, the cardiologist threads a thin tube through a vein in the leg up to the heart, and places a small mesh device across the hole. The device stays in permanently and is gradually covered by the heart’s own tissue. For many patients with the right type of defect, this approach has become the standard alternative to surgery.

The reader of this article may be a parent of a child scheduled for closure, an adult who learned about an ASD only in adulthood, or a family member supporting someone through the procedure. The information here covers both children and adults, with a dedicated section on paediatric considerations.

What Is ASD Device Closure?

To understand the procedure, it helps to start with the anatomy.

What an atrial septal defect is

Because pressure is usually higher in the left atrium than the right, blood leaks from left to right through the defect. Over time, this extra flow stretches the right side of the heart, can raise pressure in the lung arteries, and may lead to irregular heart rhythms, reduced exercise tolerance, or, less commonly, a type of stroke caused by a clot crossing through the defect.

There are several types of ASD, named by their location in the septum:

• Secundum ASD — located in the central part of the septum. This is the most common type and the one suitable for device closure.
• Primum ASD — located in the lower part of the septum, often part of a wider defect called an atrioventricular septal defect. Generally treated surgically.
• Sinus venosus ASD — located near where the large veins enter the right atrium. Usually treated surgically, although newer transcatheter techniques are being studied in selected centres.
• Coronary sinus ASD — a rare type. Treated surgically.

Device closure, as described in this article, applies primarily to secundum ASDs.

What the procedure is

ASD device closure — also called transcatheter ASD closure, percutaneous ASD closure, or device closure of ASD — is a procedure in which a closure device (called an occluder) is delivered to the heart through a catheter and positioned across the hole. The device has two flexible discs connected by a short waist. One disc opens on the left atrial side and the other on the right atrial side, sandwiching the septum between them and sealing the opening.

The device is made of a fine wire mesh, usually a nickel-titanium alloy called Nitinol, with a fabric lining that promotes tissue growth. Within several months, the body’s own tissue grows over the device, making it a permanent part of the heart wall.

The procedure is performed in a cardiac catheterisation laboratory by an interventional cardiologist with experience in structural heart procedures, often working alongside an imaging specialist who guides positioning using echocardiography.

Why ASD Device Closure Is Performed

Not every ASD requires closure. Small defects, especially those found in infants, sometimes close on their own in the first few years of life. Doctors typically recommend closure when the defect is large enough to cause meaningful extra blood flow to the right side of the heart, when there is evidence that the right heart chambers are enlarging, or when symptoms or complications have appeared.

Reasons doctors typically recommend closure include:

• Significant left-to-right shunt — when the amount of blood crossing through the defect is large enough to overload the right heart and lungs.
• Right atrial or right ventricular enlargement seen on echocardiography.
• Symptoms such as reduced exercise capacity, breathlessness, fatigue, or palpitations.
• A history of paradoxical embolism — where a clot has crossed from the venous side to the arterial side through the defect, causing a stroke or similar event.
• Early signs of raised pulmonary artery pressure, before the pressure becomes too high for closure to be safe.

Both the American Heart Association/American College of Cardiology guidelines for adult congenital heart disease and the European Society of Cardiology guidelines support closure of haemodynamically significant secundum ASDs, with device closure as the preferred approach when the anatomy is suitable.

Who Is a Candidate for Device Closure?

Suitability is decided by the cardiology team after a detailed assessment. The most important factors are the type of ASD, its size, its location within the septum, and the amount of tissue around the edges of the defect (called the rims). The device needs healthy rim tissue on most sides to anchor securely.

Device closure is generally considered suitable when:

• The defect is a secundum type.
• The defect is not too large for available device sizes (most secundum ASDs fall within this range).
• There are adequate rims of septal tissue around the defect on most sides.
• Pulmonary artery pressure has not risen to a level that would make closure unsafe.
• The patient is large enough to accommodate the delivery catheter — usually a child of around 15 kg or more, though smaller children are treated in experienced centres on a case-by-case basis.

Device closure is generally not suitable when:

• The ASD is a primum, sinus venosus, or coronary sinus type (with rare exceptions in specialised centres).
• The defect is very large or has deficient rims that cannot hold the device.
• Pulmonary vascular disease has progressed to the point that closing the defect would harm the patient.
• There are other heart defects that require open-heart repair at the same time.

Whether you or your child is a candidate is a clinical decision based on the echocardiogram, often a transoesophageal echocardiogram (TOE/TEE), and the cardiologist’s assessment of the anatomy.

Alternatives to Device Closure

The two main alternatives to device closure are surgical closure and, in some cases, watchful waiting.

Surgical ASD closure

Surgical closure is open-heart surgery in which the surgeon closes the defect either with a patch (made of pericardium or synthetic material) or with direct stitches. It requires general anaesthesia, a chest incision (usually a sternotomy, although some centres offer smaller incisions), and the use of a heart-lung machine to take over circulation during the repair.

Surgical closure remains the standard approach for:

• Primum, sinus venosus, and coronary sinus ASDs.
• Very large secundum ASDs that cannot be securely closed with a device.
• ASDs with deficient rims.
• Patients who have additional heart defects requiring repair at the same time.

Surgical closure has been performed for decades and has an excellent long-term track record. Compared with device closure, it involves a longer hospital stay, a visible chest scar, and a longer recovery period, but it can address anatomies that device closure cannot.

Watchful waiting

For small ASDs that are not causing right heart enlargement or symptoms, doctors may recommend periodic echocardiographic follow-up rather than immediate closure. Some small defects close on their own in early childhood. In adults, small defects without significant shunt may not need intervention but are still followed clinically.

The choice between device closure, surgery, and observation is made by the patient and family in discussion with the cardiology team, based on the specific anatomy and clinical picture.

How the Procedure Works

ASD device closure is performed in a cardiac catheterisation laboratory — a room equipped with X-ray imaging and continuous heart monitoring. The procedure usually takes one to two hours, although timing varies.

Step-by-step

1. Anaesthesia. Children almost always receive general anaesthesia. Adults may receive either general anaesthesia or sedation with local anaesthesia, depending on whether transoesophageal echocardiography is being used to guide the procedure.
2. Vascular access. The cardiologist places a small tube (sheath) into the femoral vein in the groin. Some procedures also require a small arterial sheath for monitoring.
3. Catheter advancement. A thin, flexible catheter is guided through the vein, into the right atrium, and across the defect into the left atrium under imaging guidance.
4. Sizing the defect. The cardiologist often uses a soft balloon to measure the stretched diameter of the defect — this helps choose the correct device size. Echocardiography is used throughout to visualise the anatomy.
5. Device delivery. The chosen closure device is loaded into a delivery sheath and advanced to the heart in a collapsed form.
6. Deployment. The left atrial disc is opened first, then pulled back gently against the septum. The right atrial disc is then opened on the other side, sandwiching the septum and sealing the hole.
7. Confirmation. Before the device is released, the cardiologist confirms that it is stable, well positioned, and not interfering with nearby structures such as the valves or surrounding veins.
8. Release and removal. The device is detached from the delivery cable. The catheter and sheath are removed, and pressure is applied to the groin to control bleeding.

Preparing for the Procedure

Preparation involves both diagnostic tests and practical steps.

Tests before the procedure

Before scheduling closure, the cardiology team will typically have completed:

• Transthoracic echocardiogram (TTE) — the standard ultrasound of the heart, used to identify and measure the ASD.
• Transoesophageal echocardiogram (TOE/TEE) — an ultrasound from inside the food pipe, which gives a clearer view of the septum and the rims of the defect. This is often required before deciding on device closure and may also be used during the procedure itself.
• Electrocardiogram (ECG) to check for rhythm abnormalities.
• Chest X-ray.
• Blood tests, including full blood count, kidney function, and clotting tests.
• In adults, sometimes a cardiac MRI or CT, particularly if anatomy is complex or pulmonary vein drainage needs to be confirmed.

Practical preparation

• Fasting — nothing to eat for around 6 to 8 hours before the procedure; clear fluids may be allowed up to a few hours before, depending on local protocol.
• Medications — tell the team about all medicines, including over-the-counter drugs and supplements. Blood thinners may need to be paused.
• Allergies — report any allergies, particularly to contrast dye, latex, or metals such as nickel.
• Companions — arrange for an adult to be present, especially for paediatric procedures and for the journey home after discharge.
• For children — familiar comforts such as a soft toy, and clear, age-appropriate explanation of what will happen, help reduce anxiety.

What Happens During and Immediately After the Procedure

Once anaesthesia is in place, the patient does not feel the device being placed. For adults who receive sedation only, the cardiologist will explain that some pressure may be felt at the groin puncture site, but the heart itself does not have pain sensation in the way other organs do.

Throughout the procedure, heart rate, rhythm, blood pressure, and oxygen levels are continuously monitored. Imaging — usually a combination of X-ray fluoroscopy and echocardiography — guides every step.

After the device is released and the catheter removed, pressure is held over the groin puncture site to stop bleeding. A pressure dressing is applied, and the patient is asked to keep the leg straight for a few hours.

Most patients are observed for several hours in a recovery area and then transferred to a regular ward. An overnight stay is standard. Before discharge, an echocardiogram is usually repeated to confirm that the device is well positioned and the defect is closed.

Recovery and Healing

The first 24 to 48 hours

• Most patients stay in hospital for one night, sometimes two.
• The groin puncture site is checked regularly for bleeding or bruising.
• A small bruise or a firm lump under the skin at the groin is common and usually resolves over a few weeks.
• Mild soreness at the groin and a slight chest awareness are common.

The first week

• Most patients return home the day after the procedure.
• Light activities — walking, sitting, eating normally — are resumed quickly.
• Heavy lifting, vigorous exercise, swimming, and contact play are usually avoided for a period determined by the cardiologist, often around one to two weeks for the puncture site and longer for vigorous sport.
• School-aged children often return to school within a week, with restrictions on physical education.
• Adults with desk-based work often return to work within a week; physically demanding jobs require a longer pause.

The first six months

• The device gradually becomes covered by the body’s own tissue, a process called endothelialisation.
• During this period, doctors typically prescribe an antiplatelet medicine, usually aspirin, sometimes with a second antiplatelet for a shorter time. The exact regimen depends on the device used and the cardiologist’s judgement.
• Antibiotic prophylaxis before dental work is often recommended for the first six months after device placement, in line with guidelines on infective endocarditis prevention.
• Follow-up echocardiograms are typically scheduled at intervals such as one month, six months, and one year, to confirm device position and complete closure.

Longer term

Once tissue has grown over the device, it becomes a permanent, well-integrated part of the heart wall. Most patients return to normal activity, including sports, after their cardiologist confirms healing. Long-term follow-up is generally less frequent but continues for life, often annually or as advised, to monitor heart rhythm and overall function.

Risks and Complications

ASD device closure in experienced centres is considered a low-risk procedure, but no procedure is without risk. Understanding the possible complications helps patients and families recognise problems early.

Common, usually minor

• Bruising or soreness at the groin puncture site.
• Small bleeding or haematoma at the access site.
• Temporary palpitations or awareness of the heartbeat in the first weeks after the device is placed.

Less common

• Arrhythmias — irregular heart rhythms, most often atrial. Some are brief and resolve on their own; others may need medication or, rarely, further treatment.
• Allergic reaction to contrast dye used during imaging.
• Infection at the access site.

Uncommon but serious

• Device embolisation — the device shifts from its intended position. This is rare and is usually managed by retrieving and replacing the device, sometimes requiring surgery.
• Cardiac perforation or erosion — the device wears into adjacent heart tissue. This is uncommon but serious and is one of the reasons regular follow-up is important.
• Thrombus formation on the device, which is why antiplatelet medication is used during healing.
• Residual shunt — a small amount of leak through or around the device. Small residual shunts often close as tissue grows over the device.
• Damage to nearby structures, such as heart valves or the conduction system that controls heart rhythm.

When to seek medical advice after going home

Contact the cardiology team or seek urgent care if you or your child develops:

• Persistent or worsening pain, swelling, redness, or bleeding at the groin site.
• Fever, especially in the weeks after the procedure.
• Chest pain, severe breathlessness, or fainting.
• A racing, pounding, or markedly irregular heartbeat that does not settle.
• Sudden weakness, slurred speech, or facial droop — symptoms that may indicate a stroke.

Life After ASD Device Closure

For most people, life after successful ASD closure is essentially the same as life without an ASD. The structural problem has been corrected, and the heart no longer has to manage extra blood flow on the right side.

Activity and exercise

Once the cardiologist has confirmed that the device is well positioned and healing is complete — usually after the six-month follow-up — most patients return to unrestricted activity, including sports. Children typically resume school physical education and play in line with the cardiologist’s clearance.

Medications

Antiplatelet medication is used for a defined period after the procedure and then typically stopped, unless there is another reason to continue it. Lifelong blood thinners are not routinely required after isolated ASD device closure.

Dental and other procedures

Antibiotic prophylaxis before dental procedures is generally advised for around six months after device placement. After this period, the device is covered by tissue and the risk of device-related endocarditis is low, so routine antibiotic prophylaxis is usually no longer required, although individual recommendations can vary.

Pregnancy

Women who have had successful ASD device closure and have normal heart function generally tolerate pregnancy well. Pre-pregnancy review with a cardiologist familiar with adult congenital heart disease is sensible to confirm that the device has healed and that there are no residual issues.

Long-term follow-up

Even after successful closure, lifelong cardiology follow-up is recommended. The intervals can be quite spaced out once healing is confirmed. Follow-up watches for late arrhythmias (particularly in adults closed later in life), changes in heart function, and the rare late device-related complications.

ASD Device Closure in Children

Children make up a large share of patients undergoing ASD device closure, and there are several considerations specific to paediatric care.

Timing

For children with significant secundum ASDs, closure is often performed in the pre-school or early school years, although timing depends on the size of the defect, the size of the child, and whether the child is symptomatic. Some small defects identified in infancy are watched first, as a portion close spontaneously by around two to three years of age.

Size and access

Because the delivery sheath used for the device is relatively large, the child generally needs to be big enough for the femoral vein to accommodate the sheath safely. A weight of around 15 kg is a common threshold, though experienced centres treat smaller children when clinically necessary.

Anaesthesia

Children almost always have general anaesthesia for the procedure, so they do not experience the catheterisation. A paediatric anaesthesia team manages airway, breathing, and pain throughout.

Recovery in children

Emotional preparation

Younger children benefit from simple, honest preparation: where they will go, who will be with them, that they will sleep through the procedure, and what the recovery room will feel like. Older children and teenagers may want more detail and can be involved in the conversation directly. Familiar items from home, a parent’s presence during induction and recovery where permitted, and a clear sense of timeline help reduce anxiety.

Growing up with a device

The closure device does not need to be replaced as the child grows. Once it is in place and healed, it remains a permanent, integrated part of the septum. Long-term follow-up is part of routine paediatric and, later, adult congenital cardiology care.

Frequently Asked Questions

Is ASD device closure a surgery?

It is a procedure, not open-heart surgery. There is no chest incision and the heart-lung machine is not used. The closure is done through a vein in the leg under imaging guidance. Some people refer to it loosely as “heart hole surgery”, but technically it is a catheter-based intervention.

How long does the device stay in?

The device stays in permanently. Within several months, the body’s own tissue grows over it, so it becomes integrated into the heart wall rather than sitting as a foreign object.

Will the device set off airport security or affect MRI scans?

Modern closure devices are generally MRI-conditional, meaning MRI scans can usually be done safely, though it is important to inform the radiology team. The devices do not typically trigger airport security scanners. A device identification card from the implanting centre is helpful to carry.

Can the device move after it is placed?

Device embolisation — movement of the device from its intended position — is rare and usually happens early, which is why patients are monitored carefully and have follow-up echocardiograms. Once tissue grows over the device, it is firmly anchored.

Will I or my child need to take medication for life?

Antiplatelet medication such as aspirin is usually given for a defined period after the procedure, often around six months, to reduce the risk of clot formation while tissue grows over the device. Lifelong medication is not typically required after isolated ASD closure, unless there is another reason for it.

Can sports and exercise be resumed?

Most patients return to full activity, including sports, once the cardiologist confirms healing — usually after the six-month follow-up. Specific timing is individualised.

What if the ASD is too large or the wrong type for a device?

If the anatomy is not suitable for device closure, surgical closure is the established alternative. It involves open-heart surgery and a longer recovery but has excellent long-term results and can address defects that device closure cannot.

Is there an upper age limit for ASD closure?

There is no fixed age limit. Adults are increasingly diagnosed with previously unrecognised ASDs and may benefit from closure if there is significant shunt, right heart enlargement, or symptoms, and if pulmonary pressures remain in a range where closure is safe. The decision is individualised.

What follow-up is needed after closure?

Echocardiograms are typically performed at intervals such as one month, six months, and one year after the procedure, and then less frequently for long-term surveillance. Lifelong cardiology follow-up is recommended to monitor heart rhythm and function.

Conclusion

ASD device closure has changed the experience of treating a common congenital heart defect. For patients with a suitable secundum ASD, it offers a way to close the hole without opening the chest, with a short hospital stay and a fast return to everyday life. For defects that the device cannot reach — primum, sinus venosus, very large secundum ASDs, or those with deficient rims — surgical closure remains the established and effective alternative.

Whichever route is chosen, the underlying goal is the same: to relieve the extra workload on the right heart, protect the lungs from long-term pressure changes, reduce the risk of arrhythmias and certain types of stroke, and allow the heart to work the way it was meant to. The right approach for any individual patient depends on the specific anatomy, the broader clinical picture, and a careful conversation with the cardiology team.