Treatments and Services

Fontan Clinic

What is the Fontan Clinic?

Seattle Children’s Fontan Clinic provides coordinated, team-based care to promote the best possible health for children and young adults who have had a Fontan procedure for a single-ventricle heart defect, like hypoplastic left heart syndrome.

Children with single-ventricle defects need a series of surgeries and cardiac catheterization procedures. These treatments cannot fully repair your child’s heart defect, but they can allow your child to grow and lead an active life.

  • Within a week of birth: The first treatment is done in the first week after birth. Based on your child’s heart anatomy, this may be a Norwood procedure or minimally invasive patent ductus arteriosus stenting.
  • At 3 to 6 months: Next, your child will have a Glenn operation, usually between 3 and 6 months of age.
  • At 3 to 5 years: Your child will have a Fontan procedure, usually around 3 to 5 years of age.

The surgeries help make up for the lack of 2 pumping chambers in your child’s heart. They help blue (oxygen-poor) blood get to your child’s lungs, and they help your child’s heart pump red (oxygen-rich) blood to the rest of their body. After the Fontan procedure, your child will have near-normal oxygen levels, which can improve their energy level and how their organs work. However, your child’s blood will not follow a normal path, and they will need ongoing care to prevent and treat conditions that may happen as they grow up.

How will the Fontan Clinic meet my needs?

The Fontan Clinic brings together a group of specialists to assess the long-term health of your child’s circulation. We recommend specific tests and evaluations every 2 to 3 years. Working with your child’s primary cardiologist, we make custom treatment plans to help your child live a full, active life. Our screening tests let us find signs of any health problems early when treatment may be more effective and provide the right combination of care to meet your child’s exact needs.

Multidisciplinary screening and treatment

Having a complex heart problem, like a single-ventricle defect, and going through multiple heart surgeries can affect other organs in your child’s body in the years ahead. For example, liver health is a concern after a Fontan procedure because the surgery affects blood flow to the liver. Doctors have learned that teens and young adults tend to have some scarring in their liver after a Fontan procedure, so frequent check-ups of liver health are important. The hepatologists in the Fontan Clinic know how to check your child’s liver health.

Our clinic also has a registered dietitian nutritionist to help with issues like trouble gaining weight and growing.

Based on your child’s situation, we will connect you with other specialists at Seattle Children’s, such as pulmonologists and endocrinologists. We work closely with experts throughout the Heart Center, such as heart surgeons, electrophysiologists, interventional cardiologists and the team in the Adult Congenital Heart Disease Program to help transition your child to adult healthcare.

Some children with single-ventricle defects have other conditions too, like children with heterotaxy, which affects many organs in the chest and belly (abdomen). They may need more specialists, such as an immunologist, gastroenterologist or general surgeon.

Coordinated care and communication

Members of your child’s Fontan Clinic team keep in close contact with each other and with you to decide the best ways to care for your child and make sure they get the treatments and services they need. Our advanced registered nurse practitioner helps coordinate everything so the process is easier on your family, you know what to expect and communication is smooth. At the end of each visit, your care team will give you a summary of recommendations from all of your child’s team members.

Exercise testing and recommendations

Doctors used to think of children’s hearts as fragile after a Fontan procedure, and they suggested children limit activity even after healing from the surgery. More recent research shows that exercise can actually help protect your child’s heart over the long term. The Fontan Clinic includes a cardiologist with special expertise in testing exercise function. They will prescribe an exercise plan made just for your child and check your child’s progress over time.

Attention to mental health and neurodevelopment

Children born with complex heart defects are at risk for mental health conditions, like anxiety and depression, and problems with how their central nervous system grows and develops. We ask you and your child about their attitude toward their heart health and how it affects their life. This is 1 way we learn more about your child so we can connect you with the right treatments, including mental health care.

An important resource for Fontan patients is Seattle Children’s Cardiac Neurodevelopmental Clinic. This clinic evaluates and treats children who have had heart surgery before their 1st  birthday. It brings together experts from Seattle Children’s Heart Center and the Center on Human Development and Disability at UW Medical Center – Montlake.

Comprehensive screening in fewer visits

To protect your child’s health, they will need certain tests on a regular schedule. For example, from time to time, your child might need a cardiac catheterization, cardiac MRI (magnetic resonance imaging) and exercise testing to check their heart health and a liver biopsy to see how their liver is doing. We understand this can be a lot to manage, especially if you have to travel for these tests. We do our best to coordinate your child’s care so you can make fewer visits to Seattle Children’s and get more out of each visit.

Evidence-based approach

Knowledge is growing quickly about how the body works after a Fontan procedure and how to help the heart and other organs function best. Our experts add to this knowledge by researching care for people who have had Fontan procedures, and we follow the most up-to-date scientific guidance on how to get the best results for your child so they will thrive.

Care for heart failure

Over time, your child’s heart may have trouble moving blood around their body. The Fontan Clinic has a strong focus on checking your child for subtle signs of heart failure — before your child even feels a change — so we can provide treatment early and give your child the best heart health for as long as possible. Doctors in Seattle Children’s Heart Failure Program provide a range of therapies to lower the workload of the heart or help the heart pump. For children who need a heart transplant, our outcomes are among the best in the nation.

What kind of patients are treated by the Fontan Clinic?

We treat children who have had a Fontan procedure for a wide range of single-ventricle defects, including:

Advancing Treatment for Children

The Fontan Clinic team leads research to improve outcomes for children and young adults everywhere who have had a Fontan procedure. Examples of our research include:

  • A multicenter trial to test if the medicine udenafil can help children exercise after a Fontan procedure
  • A study to see if 3D echocardiography can replace cardiac MRI to check children’s hearts because 3D echo is more widely available and children do not need to have sedation, like they often do for an MRI

Scheduling an Appointment With the Fontan Clinic

Who’s on the team?

The Fontan Clinic includes cardiologists, cardiac intensivists, hepatologists, nurse practitioners, nurses and registered dietitian nutritionists.

Advanced registered nurse practitioner

  • Jessica G Mooney, ARNP

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Registered dietitian nutritionist

  • Mariah Nicole Kassuhn, MS, RDN, CD

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  • Emily Bay, RN

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Medical assistant

  • Jestine Bianca Gregoria, CMA

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Contact Us

Contact the Heart Center at 206-987-2515 for a referral, a second opinion or more information.

Providers, see how to refer a patient.

Telemedicine at Seattle Children’s

You may be offered a telehealth (virtual) appointment. Learn more.

Paying for Care

Learn about paying for care at Seattle Children’s, including insurance coverage, billing and financial assistance.