How the Extracardiac Fontan Procedure Reroutes Blood Flow: A Guide for Parents

The surgeon draws the heart on the back of a paper towel. One circle for the pump. A stubby tube coming out of the top, another coming up from the bottom. Then a line across the bottom tube, redirected sideways toward the lungs. “That,” she says, “is what we are going to build.” The parents nod. Neither of them will remember a word of the next five minutes.

If that scene feels familiar, this guide is for you. The extracardiac Fontan procedure explained for parents is not a simple thing, because the surgery itself asks a child’s body to do something no healthy heart does: send blood to the lungs without pumping it there. Once that idea clicks, almost everything else about the operation, the recovery and the long follow-up starts to make sense.

What follows is the version of that paper-towel drawing with the labels filled in, grounded in guideline-level evidence rather than reassurance for its own sake.

The extracardiac Fontan procedure explained for parents: what problem it solves

A healthy heart has two pumping chambers, called ventricles. The right ventricle pushes oxygen-poor blood a short distance into the lungs at low pressure. The left ventricle drives oxygen-rich blood around the whole body at high pressure. Two pumps, two jobs, two circuits stacked in a figure eight.

Some children are born with only one ventricle able to do useful work. The umbrella term is single-ventricle heart disease. Hypoplastic left heart syndrome, where the left side is severely underdeveloped, is the most familiar example; tricuspid atresia, double-inlet left ventricle and several other defects lead to the same practical problem (CDC). With one pump, oxygen-poor and oxygen-rich blood mix, so the body runs on a blend. Skin can look dusky, feeding tires the baby, and the single ventricle works harder than any chamber is built to.

The Fontan concept, named after the French surgeon who first described it, reframes the problem. Instead of trying to build a second pump, it removes the need for one. If the veins returning from the body are connected directly to the arteries that lead into the lungs, blood can drift through the lungs on its own pressure gradient. The single ventricle is then left with a single job: pumping oxygen-rich blood to the body.

“Extracardiac” simply means outside the heart. In this version of the operation, the connection is made with a tube that sits beside the heart rather than a channel built inside it. The Fontan is not a repair in the sense of making the heart normal. It is a rerouting. Parents who hold onto that distinction tend to find the years afterward less confusing, because the follow-up care is all about how a rerouted circulation behaves over time.

What actually happens during the extracardiac Fontan operation

The operation is done through the front of the chest, usually reopening the same incision line as earlier surgeries. The surgical team locates the inferior vena cava, the large vein that brings blood back from the legs, abdomen and lower body into the heart. That vein is divided just before it enters the heart, and the opening on the heart side is closed.

A conduit, which is a straight or gently curved synthetic tube usually made from a durable plastic such as polytetrafluoroethylene, is stitched to the cut end of the vein. The other end is sewn onto the underside of the pulmonary artery, the vessel that carries blood into the lungs. The superior vena cava, which drains the head and arms, was already joined to the pulmonary artery at the previous stage, so once the conduit is in place all the body’s venous blood reaches the lungs without passing through the heart (Cleveland Clinic).

Many teams perform this on cardiopulmonary bypass, a machine that takes over the work of the heart and lungs during surgery. Some centers complete an extracardiac Fontan without stopping the heart, because the conduit sits outside it; whether bypass is used depends on the child’s anatomy and the team’s judgment. Neither approach is right for every patient.

Before closing, the surgeon may create a fenestration, a deliberate small opening between the conduit and the heart that acts as a pressure release valve. Chest drains are placed to remove fluid, temporary pacing wires may be left in case the heart rhythm needs support, and the child goes to the pediatric cardiac intensive care unit. Operating time varies with anatomy and prior scarring; your team can give a realistic range for your child rather than a general figure.

How the Fontan reroutes blood flow: follow one drop from the toes

Imagine a single red blood cell leaving a toe. It has handed its oxygen to the muscle and is heading home. In a two-ventricle heart it would travel up the inferior vena cava into the right atrium, drop into the right ventricle, get a push into the lungs, pick up oxygen, return to the left side of the heart and be pumped back out.

After an extracardiac Fontan the route is shorter and stranger. The cell rides the inferior vena cava upward and, instead of entering the heart, slides into the conduit. The tube carries it past the heart, alongside it rather than through it, and delivers it into the pulmonary artery. From there it enters the lungs. Nothing pumped it. It moved because the pressure in the veins was slightly higher than the pressure in the lung vessels, the same way water runs downhill through a garden hose without a pump when the tap end is raised.

Inside the lungs the cell collects oxygen and drains through the pulmonary veins into the heart, where it meets blood from the other body veins that took the same detour. The single ventricle fills with this now fully oxygenated blood and pumps it into the aorta and out to the body. The circulation has become a single loop instead of a figure eight.

The hidden cost is that the lungs have become a resistor in the line. Anything that stiffens the lung vessels, thickens the blood, or raises pressure inside the chest slows the flow. This is why the team pays so much attention to breathing, hydration and lung health after surgery. The AHA’s scientific statement on Fontan circulation describes this dependence on low lung resistance as the defining feature of the circulation, and it shapes nearly every follow-up decision for life.

Where the extracardiac Fontan sits in the three-stage pathway

The Fontan is almost never a first operation. Newborn lungs have thick, high-resistance vessels, and blood cannot drift through them passively. So the pathway is staged, giving the lungs time to mature while keeping the child alive and growing in between.

The first stage, performed in the first days or weeks of life, depends on the specific defect. For hypoplastic left heart syndrome it is usually the Norwood operation, which rebuilds the aorta so the single ventricle can supply the body, and places a small shunt to supply the lungs (Mayo Clinic). Other children may need a band on the pulmonary artery to protect the lungs from too much flow, or a shunt alone.

The second stage, often called the Glenn or hemi-Fontan, is typically done in the first year of life. The superior vena cava is connected to the pulmonary artery, so blood from the head and arms already flows passively to the lungs, and the earlier shunt is removed (Mayo Clinic).

The third stage is the Fontan itself, usually performed between around 18 months and 4 years of age, once the child has grown and the lung vessels have settled to adult-like low resistance (Mayo Clinic). Timing is individual. Some teams operate earlier because oxygen levels are falling; some wait for growth so an adult-sized conduit will fit comfortably.

Between stages, children live with mixed circulation and oxygen levels well below normal, which is why these are sometimes called the “interstage” months and are watched closely. Parents often describe the Fontan as the finish line. It is more accurate to call it the last major planned surgery. Follow-up continues indefinitely, and some children will need further catheter procedures or operations later (NHS).

Who is usually offered the Fontan, and who is usually asked to wait

The operation only works if blood can travel through the lungs without help, so the team assesses that before anything else. A cardiac catheterization, in which a thin tube is guided from a leg vessel into the heart to measure pressures directly, is standard preparation. Cardiac MRI is increasingly used alongside or instead of some catheter measurements (AHA).

Children generally proceed when several conditions line up. Pressure in the pulmonary arteries is low. The single ventricle squeezes well and relaxes normally. The valve between the atrium and that ventricle does not leak significantly. The pulmonary arteries are of adequate size without narrowings. Oxygen levels have drifted low enough, or the child has grown enough, that the benefit of completing the circulation outweighs waiting.

The team may recommend waiting, or a different plan, when any of those pieces is missing. Common reasons include a ventricle that has become stiff or weak after earlier surgery, a leaking valve that first needs repair, narrowed pulmonary arteries that need widening by balloon or stent, or lung vessel pressures that are too high for passive flow. Very small children may be asked to grow before receiving a conduit that will not enlarge with them.

Some children are never good candidates for a Fontan, and their teams discuss other paths, which can include continuing with a Glenn circulation, heart transplantation, or in a few cases a different type of repair if the anatomy allows. None of this is a verdict on how well parents have done. These decisions rest on measurements, and they belong to the treating team, who will explain which findings drove them. Asking to see the catheter numbers explained on paper is reasonable and usually welcomed.

Lateral tunnel vs extracardiac Fontan: how the two techniques compare

There are two main ways to route lower-body blood to the lungs. The lateral tunnel builds a channel inside the right atrium using a patch and part of the atrial wall. The extracardiac conduit, the subject of this guide, uses a tube outside the heart. Both achieve the same physiology.

Feature	Extracardiac conduit	Lateral tunnel
Where the pathway sits	Outside the heart, beside the right atrium	Inside the right atrium, using its wall
Growth potential	None; the tube is fixed in size, so an adult-sized conduit is usually chosen	Partial; part of the pathway is living tissue
Suture lines inside the atrium	Few or none	Extensive, potentially affecting rhythm tissue
Need to stop the heart	Often possible without opening the heart	Requires opening the heart on bypass
Fenestration	Possible, placed between conduit and atrium	Possible, placed in the baffle

Many surgical teams have moved toward the extracardiac approach, partly because fewer stitches inside the atrium may mean less disturbance of the heart’s electrical tissue, and partly because the operation can sometimes be done with the heart beating. The lateral tunnel keeps some ability to grow and avoids a length of synthetic material sitting in the venous stream.

What does the evidence say? The AHA scientific statement notes that long-term comparisons have not shown a clear, consistent winner for outcomes that matter most, such as rhythm problems, clot formation or ventricular function. Differences between individual centers and patients are larger than differences between the techniques. If your team recommends one approach, the honest reason is usually their experience and your child’s anatomy, not a proven superiority. Either way, the rerouted circulation behaves the same afterward and needs the same lifelong follow-up.

What is a fenestration, and why do some children get one?

A fenestration is a small, deliberately created hole, a few millimeters across, connecting the Fontan pathway to the heart’s atrium. It sounds like a step backward. The point of the Fontan is to send all venous blood to the lungs, and a fenestration lets a little of it skip the lungs and mix into the ventricle.

The reason is pressure. In the days after surgery the lungs are irritable, the body is swollen, and the circulation has not yet found its new equilibrium. Venous pressure can climb. When it does, fluid leaks out of vessels into the chest and abdomen, and the amount of blood reaching the single ventricle can fall, dropping blood pressure. A fenestration acts as an overflow. If venous pressure rises, a small stream of blood escapes into the atrium, keeping the ventricle filled and the pressure in check. The trade is a modest fall in oxygen saturation, since some unoxygenated blood is now in the mix.

Evidence on fenestration has been debated for decades. Some centers fenestrate almost every child; others reserve it for higher-risk anatomy or borderline pressures. The AHA statement summarizes that fenestration is associated with shorter chest-drain duration and hospital stay in several studies, while the effect on long-term outcomes is less clear. Reasonable teams disagree.

Fenestrations often close on their own over months. If one stays open and oxygen levels remain lower than the team would like, it can usually be closed later with a small device delivered by catheter through a leg vein, without further surgery. Sometimes the team prefers to leave it open. Parents sometimes hear “we left a hole in the heart” and worry the operation is incomplete. It is not. The hole is part of the design.

How risky is the Fontan procedure? Fontan procedure risks in plain terms

Every parent asks this, and deserves a straight answer: this is major open-heart surgery on a child who has already had two, in a circulation that is unusual by design. It is not minor. It is also a procedure that specialized teams perform routinely, and the immediate risks today are very different from those in the early decades of the operation (AHA).

The most common early problem is fluid. Because venous pressure is higher than normal, fluid leaks into the space around the lungs, called a pleural effusion. Chest drains stay in place until this settles, and this single issue is the most frequent reason a hospital stay stretches longer than expected (Cleveland Clinic). Occasionally the fluid is milky lymph rather than clear fluid, a condition called chylothorax, which needs dietary changes and patience.

Other early risks include bleeding, especially where earlier surgery left scar tissue; irregular heart rhythms, called arrhythmias, from irritation of the heart’s electrical tissue; low blood pressure if the ventricle does not fill well; infection of the wound or chest; and clots, since blood moving slowly through a synthetic tube tends to clot more readily than blood in a pumping chamber. A small number of children need to have the Fontan connection taken down temporarily if the new circulation cannot be tolerated.

Less common but serious risks include stroke, kidney injury, and death. General surgical risks are described neutrally on the MedlinePlus pediatric heart surgery page. Your team’s job is to translate these into what applies to your child, because risk depends heavily on ventricular function, pulmonary pressures and prior complications. Published percentages vary widely between studies and populations, which is why this guide does not quote a single number. Ask your team for theirs, and ask what makes your child higher or lower than average.

Fontan surgery recovery time: what the days and weeks afterward usually look like

The first stop is the intensive care unit. Children arrive with a breathing tube, several intravenous lines, chest drains and often temporary pacing wires. Most are supported on a ventilator briefly, and teams generally aim to remove the breathing tube early, because breathing on your own lowers pressure in the chest and helps blood drift through the lungs. That is a physiological point, not just a comfort one.

Over the next several days the drains become the main storyline. Nurses measure how much fluid comes out each shift. Medicines that encourage the kidneys to shed fluid, called diuretics, are commonly used, with type and duration decided by the prescribing clinician. When drainage falls to a low, steady trickle, the tubes come out. Cleveland Clinic describes a typical hospital stay of roughly one to two weeks, longer if drainage persists.

Once on the regular cardiac ward, the work is getting a toddler to eat, move and sleep. Physical therapists encourage walking within days, which improves lung expansion and reduces clot risk. Pain is managed with a plan set by the team; parents should ask what the plan is and how they can help with comfort, distraction and routine.

Discharge typically comes with instructions covering wound care, fluid intake, a possible blood-thinning medicine, and a follow-up schedule. Many children return to their normal energy within a few weeks, and parents often notice pinker lips and less breathlessness during play. Others take longer, especially if a chylothorax has required a special diet. MedlinePlus notes that recovery from pediatric heart surgery varies widely between children, and comparing your child’s timeline to another family’s rarely helps. Fever, rapid breathing or a swollen belly after discharge are reasons to call, covered in detail later in this guide.

What is the Fontan paradox? Why this circulation runs at a higher pressure

The phrase sounds like something from a physics textbook, and it nearly is. The Fontan paradox describes an odd pairing that exists only in this circulation: the veins run at higher pressure than normal while the lungs receive blood at lower pressure than normal. In a healthy person the right ventricle lifts venous blood from a pressure of a few millimeters of mercury up to the pressure needed to push it through the lungs. Remove the pump, and the two pressures must meet in the middle.

The result is a body whose veins are permanently a little congested and lungs that are permanently a little underfilled. The AHA scientific statement calls elevated central venous pressure and reduced cardiac output the two intrinsic features of Fontan physiology, and nearly every long-term complication traces back to one of them.

Congested veins matter for the liver, which sits directly downstream of the inferior vena cava. Years of raised pressure can gradually stiffen liver tissue, a pattern called Fontan-associated liver disease, which is why liver checks become part of routine follow-up. Congested veins also explain the tendency to retain fluid, the swelling in the abdomen or legs that some children develop, and a rare condition called protein-losing enteropathy, in which protein leaks from the gut wall.

Underfilled lungs mean limited reserve. A child with a Fontan can walk, play and attend school, but the circulation cannot ramp up output during exercise the way a two-ventricle heart does, because there is no pump to push more blood through the lungs on demand. Exercise capacity is commonly reduced compared with peers, though regular activity helps and is encouraged by the AHA statement. The paradox is not a failure of surgery. It is the price of a circulation with one pump, and the reason lifelong surveillance exists.

Fontan life expectancy: what the evidence actually shows about the long term

Parents search this question at two in the morning, and the honest answer is more hopeful than the search results often suggest, while still uncertain. Here is why.

The children who received the earliest Fontan operations are now adults in middle age. Everything known about very long-term outcomes comes from them, and they had operations that differ in technique, timing and aftercare from what a child receives today. Older versions connected the atrium itself to the pulmonary artery, an approach largely abandoned because the stretched atrium caused rhythm problems and clots. The extracardiac and lateral tunnel methods replaced it. So published figures describe a past that current patients may not share.

The AHA scientific statement on Fontan circulation states that the majority of children who complete the Fontan pathway now survive into adulthood, and describes a growing population of adults living with this circulation who need specialized care. It does not offer a single life expectancy number, and neither will this guide, because no honest one exists for a child operated on today.

What the evidence does describe is a circulation that tends to accumulate wear over decades rather than fail suddenly. Ventricular function can decline, rhythm problems can emerge, the liver can stiffen, and a proportion of adults eventually need advanced therapies including heart transplantation. The statement frames long-term care around anticipating these problems through scheduled imaging, blood tests, rhythm monitoring and exercise testing, so that interventions happen early.

Two things are worth holding onto. First, outcomes have improved steadily with each generation of surgical technique and follow-up, and the AHA notes that continued improvement is expected. Second, the single most important thing a family controls is staying connected to a congenital heart team through adolescence and into adulthood, when patients are most likely to drift away from care.

Living with a Fontan: follow-up, activity, the liver and everyday childhood

The rhythm of life after a Fontan is defined less by restriction than by appointments. Clinic visits are frequent in the first year, then usually settle to a regular schedule with an echocardiogram, which is an ultrasound scan of the heart, at most visits. Over time the team adds periodic cardiac MRI, blood tests, liver imaging, exercise testing and rhythm monitoring, following the surveillance framework laid out in the AHA scientific statement.

Medicines are common but individualized. Many children take an antiplatelet agent or an anticoagulant, medicines that make blood less likely to clot, because blood moving slowly through a conduit is prone to clotting. Some take medicines that reduce the ventricle’s workload. Which medicines, whether any, and for how long are decisions for the prescribing team, and the balance of evidence for several of them is still evolving.

Activity is encouraged. The AHA statement supports regular, moderate exercise for people with a Fontan and notes that fitness is associated with better outcomes. Children generally attend school, play with friends and join in sports, with the team advising on intensity. Staying well hydrated matters more than for other children, because dehydration reduces the venous pressure that drives blood to the lungs.

The liver deserves a plain explanation. Fontan-associated liver disease develops gradually in most people with this circulation because of chronic venous congestion. It rarely causes symptoms in childhood, and the goal of surveillance is to detect changes before they matter (AHA).

Illness needs early attention. A vomiting bug that would be a nuisance for another child can lower blood volume enough to trouble a Fontan circulation, so teams usually give clear guidance on when to seek review. Vaccination on the standard schedule, including annual influenza vaccination, is recommended by the CDC for children with heart disease.

What people often get wrong about the Fontan procedure

Confusion around this operation is understandable, and some of the myths cause real worry. A few of the most common, corrected.

“The Fontan fixes the heart.” It does not. The heart still has one working ventricle. The operation reroutes venous blood so that ventricle can serve the body alone. Children with a Fontan have a functional, durable circulation, but not a normal one, and follow-up continues for life (NHS).

“Extracardiac means the surgery does not involve the heart.” The conduit sits outside the heart, which may allow the operation to be done without stopping it, but this is still major cardiac surgery through the chest with all the associated risks.

“The tube grows with my child.” Synthetic conduits do not grow. Surgeons choose a size intended to serve the child into adulthood, which is one reason teams often prefer to wait until a child has reached a certain size before operating.

“A fenestration means the surgery went wrong.” A fenestration is a planned pressure-release opening, and many teams create one deliberately. It may close on its own or be closed later by catheter.

“Oxygen levels should be 100 percent afterward.” The AHA statement describes saturations in the low to mid 90s percent range as typical after Fontan completion, lower if a fenestration is open. Numbers slightly below the textbook normal are expected, not alarming.

“Exercise is dangerous.” Regular moderate activity is recommended and associated with better health in this population (AHA). The team advises on limits, but the default is participation.

“Once the Fontan is done, we are finished with surgery.” Many people with a Fontan never need another operation, but catheter procedures, rhythm procedures and, in some adults, transplantation are part of the landscape, which is why the pathway is described as staged palliation rather than a final repair.

Questions to ask your care team about the extracardiac Fontan procedure explained for parents

The consultation before a Fontan tends to be long, technical and emotional, which is a poor combination for remembering anything. Writing questions down beforehand helps, and so does asking one person to take notes while the other listens. These are the questions experienced families most often wish they had asked.

• What did the catheterization and imaging show about my child’s lung pressures, ventricle function and valves, and how did those findings shape your recommendation?
• Will you use an extracardiac conduit or a lateral tunnel, and why that choice for my child?
• Do you plan a fenestration? If so, what would prompt you to close it later, and how?
• Will the operation be done on cardiopulmonary bypass, and what does that mean for recovery?
• What are the most likely complications for a child with my child’s anatomy, and what are the warning signs we should watch for on the ward?
• How long do you expect the intensive care and hospital stay to be, and what usually extends it?
• Which medicines might my child go home on, what do they do, and who manages them?
• How will pain and anxiety be managed, and how can we help with comfort?
• What activity is safe in the first weeks, and when can my child return to daycare or school?
• What does the follow-up schedule look like for the first year, and then long term?
• How will you monitor the liver, rhythm and ventricle over the years, and when should we expect those tests to start?
• When should my child transition to an adult congenital heart program, and how does that handover work?
• Who do we call at night or on weekends if something worries us?

Every answer will be specific to your child. Bring the list back to later visits too; the questions that matter change as the child grows, and the team expects that.

When to call your doctor: red-flag signs after Fontan surgery

Fontan circulation has little reserve, so problems that another child would shrug off can escalate faster. Your team will give you a direct contact number and specific thresholds. The signs below are the ones congenital heart teams most consistently ask families to report, drawn from guidance summarized by the AHA and general post-surgical advice from MedlinePlus.

Call emergency services or go to the nearest emergency department immediately if your child has severe difficulty breathing, blue or gray lips or face that does not improve, collapses or is unusually difficult to rouse, has a seizure, shows sudden weakness on one side or a drooping face, or has heavy bleeding that does not stop with pressure.

Call your cardiac team the same day if you notice breathing that is faster or more effortful than usual at rest; a new or worsening cough; oxygen saturation readings persistently below the range your team gave you; a fever above the threshold on your discharge instructions, especially in the first weeks after surgery; redness, swelling, warmth or discharge at the wound; a swollen abdomen, puffy eyes or legs, or rapid weight gain over a day or two; vomiting or diarrhea that prevents your child from keeping fluids down, or fewer wet diapers than normal; a racing, irregular or unusually slow heartbeat, or episodes of paleness and sweating; unusual bruising, blood in urine or stool, or nosebleeds that are hard to stop, particularly if your child takes a blood-thinning medicine; and any new swelling or pain in one leg or arm.

Trust the pattern you know. Parents of children with single-ventricle hearts are often the first to notice a subtle change in color, energy or breathing, and teams would far rather hear about a concern that turns out to be minor than miss one that was not. If you are unsure whether something counts, call. The decision about what happens next always sits with the treating team.

Frequently asked questions

What is the average life expectancy of someone with Fontan circulation?

No reliable single number exists for a child operated on today. Long-term data come from adults who had earlier, now-abandoned techniques, and the AHA scientific statement on Fontan circulation reports that the majority of children completing the pathway now reach adulthood, with outcomes improving over successive generations. The statement emphasizes lifelong surveillance to detect ventricular, rhythm and liver changes early rather than quoting a life expectancy figure.

How risky is the Fontan procedure?

It is major open-heart surgery with real risks, including prolonged fluid drainage around the lungs, bleeding, rhythm disturbances, clots, infection and, rarely, stroke or death. Risk depends heavily on the child’s ventricular function, lung pressures and prior complications, which is why published figures vary widely and why this guide does not quote one. Your team can give a risk estimate specific to your child’s anatomy and explain what raises or lowers it.

What is the Fontan paradox?

The Fontan paradox is the combination of higher-than-normal pressure in the body’s veins and lower-than-normal pressure and flow in the lungs. Without a pumping chamber between them, the two pressures must meet in the middle. The AHA scientific statement identifies raised venous pressure and reduced cardiac output as the two intrinsic features of Fontan physiology, and most long-term complications, including liver stiffening and limited exercise reserve, trace back to them.

How long does it take to recover from Fontan surgery?

Hospital stays are typically around one to two weeks, extended when fluid drainage around the lungs persists (Cleveland Clinic). Many children return to normal energy within several weeks, though MedlinePlus notes that recovery after pediatric heart surgery varies widely. Full follow-up continues for life, with clinic visits frequent in the first year and then settling to a regular schedule set by the cardiac team.

What is the difference between lateral tunnel and extracardiac Fontan?

Both route lower-body blood to the lungs. The lateral tunnel builds a channel inside the right atrium using a patch and atrial wall; the extracardiac approach uses a synthetic tube outside the heart. The extracardiac version involves fewer stitches inside the heart and can sometimes be done without stopping it, while the lateral tunnel retains some growth potential. The AHA statement reports no clear long-term winner between them.

What are the main Fontan procedure risks in the first weeks?

Fluid collecting around the lungs is the most frequent early problem and the main reason chest drains stay in longer. Other early risks include bleeding from scar tissue, irregular heart rhythms, low blood pressure if the ventricle fills poorly, wound or chest infection, and clots in the conduit. Less common serious risks include stroke and kidney injury. Teams monitor for all of these in intensive care and on the ward.

Why does my child need a fenestration in the Fontan?

A fenestration is a small, deliberately created opening between the Fontan pathway and the atrium that acts as a pressure-release valve. If venous pressure rises after surgery, a little blood escapes into the heart, keeping the ventricle filled and reducing fluid leakage, at the cost of slightly lower oxygen levels. Many close on their own; others can be closed later by catheter if the team decides that is best.

What oxygen level is normal after Fontan surgery?

Oxygen saturation after Fontan completion typically sits in the low to mid 90s percent range, according to the AHA scientific statement, and may be somewhat lower if a fenestration is open. Readings of 100 percent are not expected. Your team will give you a target range specific to your child and tell you what reading should prompt a call, so use their numbers rather than a general figure.

Can a child with a Fontan play sports and go to school?

Yes, in most cases. The AHA scientific statement encourages regular moderate exercise for people with Fontan circulation and links fitness to better outcomes. Exercise capacity is usually lower than peers because the circulation cannot boost lung blood flow on demand, so the team advises on intensity and on staying well hydrated. School attendance is the norm once recovery from surgery is complete.

What is Fontan-associated liver disease?

It is gradual stiffening and structural change in the liver caused by years of raised pressure in the veins that drain into the inferior vena cava, which sits directly upstream of the Fontan conduit. It develops in most people with this circulation, rarely causes symptoms in childhood, and is monitored with periodic blood tests and imaging. The AHA statement recommends scheduled liver surveillance so any changes are found early.

References

• Pediatric heart surgery
• About Hypoplastic Left Heart Syndrome
• Congenital heart disease: Treatment

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.