The Fontan Outcomes Network: Findings After 2 Years and 1121 Participants

T Thomas M. Glenn (Pediatrics and Cardiology, Baylor College of Medicine and Texas Children’s Hospital, Houston (T.M.G., S.J.D.).) N Nadine A. Kasparian S Shahnawaz Amdani D David Renaud (Department of Child and Adolescent Health, Division of Pediatrics III–Cardiology, Pulmonology, Allergology and Cystic Fibrosis, Medical University of Innsbruck, Austria (D.R.).) M Michael V. DiMaria (Pediatrics and Cardiology, C.S. Mott Children’s Hospital, University of Michigan, Ann Arbor (M.V.D., K.R.S.; M.V.D. now with HCA HealthONE Rocky Mountain Children’s at Presbyterian St. Luke’s, Denver, CO).) J Jennifer Teh (Heart Institute (J. Teh, N.A.P.), Children’s Hospital Los Angeles, CA.) D David M. Leone (Heart Institute (N.A.K., D.M.L., R.V., J. Theobald, J.B.A., A.R.O.)) A Arjun K. Mahendran (Pediatrics, Texas Center for Pediatric and Congenital Heart Disease, Dell Medical School at The University of Texas at Austin/Dell Children’s Medical Center (A.K.M.).) N Nancy A. Pike (Heart Institute (J. Teh, N.A.P.), Children’s Hospital Los Angeles, CA.) S Stephen J. Dolgner (Pediatrics and Cardiology, Baylor College of Medicine and Texas Children’s Hospital, Houston (T.M.G., S.J.D.).) A Andrew L. Cheng (Pediatrics and Cardiology (A.L.C.), Children’s Hospital Los Angeles, CA.) R Rahul H. Rathod S Sumeet S. Vaikunth (Internal Medicine and Pediatrics, Hospital of the University of Pennsylvania, Philadelphia (S.S.V.).) S Surendranath R. Veeram Reddy (Pediatrics and Cardiology, Children’s Health, UT Southwestern, Dallas, TX (S.R.V.R.).) R Rohith Vanam (Heart Institute (N.A.K., D.M.L., R.V., J. Theobald, J.B.A., A.R.O.)) J Jeff Theobald (Heart Institute (N.A.K., D.M.L., R.V., J. Theobald, J.B.A., A.R.O.)) K Kurt R. Schumacher (Pediatrics and Cardiology, C.S. Mott Children’s Hospital, University of Michigan, Ann Arbor (M.V.D., K.R.S.; M.V.D. now with HCA HealthONE Rocky Mountain Children’s at Presbyterian St. Luke’s, Denver, CO).) S Sarah A. Hummel J Jennifer Conway D David J. Goldberg (Pediatrics (D.J.G.), Children’s Hospital of Philadelphia, PA.) D Dala Zakaria (Pediatrics and Cardiology, Arkansas Children’s Hospital, Little Rock (D.Z.).) S Sarah B. Clauss (Pediatrics and Cardiology, Children’s National Hospital, Washington, DC (S.B.C.).) D Divya Suthar (Pediatrics and Cardiology, Children’s Healthcare of Atlanta, GA (D.S.).) R Roni M. Jacobsen (Pediatrics and Cardiology, Children’s Hospital Colorado, Aurora (R.M.J.).) E Evonne M. Morell (Pediatrics and Cardiology, Children’s Hospital of Pittsburgh of UPMC, PA (E.M.M., T.A.; T.A. now with Pediatrics and Cardiology, Children’s Health, UT Southwestern, Dallas, TX).) J John C. Dykes (Pediatrics and Cardiology, Lucile Packard Children’s Hospital, Stanford University, Palo Alto, CA (J.C.D.).) A Angela J. Weingarten (Medicine and Pediatrics, Divisions of Cardiovascular Medicine and Pediatric Cardiology, Monroe Carrell Jr Children’s Hospital, Vanderbilt University Medical Center, Nashville, TN (A.J.W.).) D Deepti P. Bhat (Pediatrics and Cardiology, Phoenix Children’s Hospital, AZ (D.P.B.).) B Benjamin E. Reinking (Pediatrics and Cardiology, University of Iowa Stead Children’s Hospital, Iowa City (B.E.R.).) T Tarek Alsaied C Carole Lannon (James M. Anderson Center for Health Systems Excellence (C.L.)) K Kiona Y. Allen (Pediatrics and Cardiology, Ann & Robert H. Lurie Children’s Hospital of Chicago, Northwestern Feinberg School of Medicine, Chicago, IL (K.Y.A.).) J Jeff B. Anderson (Heart Institute (N.A.K., D.M.L., R.V., J. Theobald, J.B.A., A.R.O.)) L Lacie B. Patterson (Sisters by Heart, Valley Center, CA (L.B.P.).) D David W. Brown (Pediatrics and Cardiology, Boston Children’s Hospital, MA (R.H.R., D.W.B.).) R Richard James (Medical Education, Library Services, Nemours Children’s Health, Wilmington, DE (R.J.).) J Jack Rychik (Cardiology (D.J.G., J.R.), Children’s Hospital of Philadelphia, PA.) A Alexander R. Opotowsky (Heart Institute (N.A.K., D.M.L., R.V., J. Theobald, J.B.A., A.R.O.)) J Jeremy T. Affolter D Diane Aguero A Alaa Aljiffry S Saleem Almasarweh J Julie Bonn J Jamie N. Colombo P Paul Critser M Meghan A. Didier K Kathryn M. Dodds F Francine Erenberg D David M. Finkelstein T Therese M. Giglia S Salil Ginde M Molly Gord J Joseph N. Graziano J Jessica Haley S Stephanie S. Handler J Jesse Hansen A Anyir Hsieh A Alicia K. Hutson N Natalie M. Jayaram O Omar M. Khalid M Matthew S. Lemler A Andrew S. Mackie A Amanda McCormick K Kimberly L. Moore L Lakshmi Nagaraju M Melanie Parent T Trudy Pierick M Michelle S. Ploutz P Pierangelo Renella K Kate Robb N Nancy Rudd I Ilana Schwartz K Kavisha M. Shah R Rachel J. Shustak J Jose Silva Sepulveda M Megan Soohoo E Eileen Stewart M Michelle M. Steltzer S Sherzana Sunderji K Karen M. Texter R Rocky Tsang C Casey Vogel J Jodie K. Votava-Smith J Justin Weigand A Alicia N. Wilmoth F Fred Wu A Adel K. Younoszai

Abstract

BACKGROUND: Survival after Fontan palliation for single ventricle heart disease has improved substantially, yet the long-term trajectory remains poorly defined. The Fontan Outcomes Network, a learning health network of 38 congenital heart centers in the United States and Canada, was established to address this gap. We report baseline characteristics and early findings from the first 1121 participants enrolled in this prospective clinical registry. METHODS: We performed a cross-sectional analysis of individuals who had undergone Fontan palliation enrolled in the Fontan Outcomes Network from August 2022 through August 2024. Demographic, clinical, imaging, procedural, and medication data were analyzed descriptively, overall and by age group (<12, 12 to <18, and ≥18 years). RESULTS: A total of 1121 participants were enrolled (mean age, 16.3±10.2 years; 471 [42%] female). Hypoplastic left heart syndrome (n=431 [38.5%]) and right ventricular–dominant anatomy (n=615 [54.9%]) were the most common primary cardiac diagnoses, especially in younger age groups. Extracardiac conduit was the most frequent Fontan type (n=749 [66.8%]). Typical Fontan-related adverse events were noted in 59% of cases (n=662), including chylous pleural effusions (n=108 [9.6%]), Fontan thrombosis (n=79 [7.1%]), and nonperioperative stroke (n=73 [6.5%]). A history of arrhythmia was present in 41.3% of patients (n=463) overall, increasing with age. Acquired comorbidities were present in 57.5% of patients (n=645), including asthma (n=132 [12%]) and sleep apnea (n=103 [9%]), with burden increasing by age. Antithrombotic medication use was nearly universal. Use of other medications varied widely by age, and included β-blockers, angiotensin-converting enzyme inhibitors, and pulmonary vasodilators. A clinical diagnosis of an anxiety disorder was present in 34.1% of patients (n=382), including 48.1% of adults (n=194 of 403), and antidepressants were prescribed in 11.8% of patients (n=132), including 23.6% of adults (n=95 of 403), highlighting the mental health needs of this population. CONCLUSIONS: The Fontan Outcomes Network includes one of the largest prospective, multi-institutional data sets of patients with Fontan circulation. These initial findings demonstrate the potential for a collaborative learning health network to advance research and quality improvement for this rare disease population.

Article Details

Journal Circulation
Volume / Issue Vol. 153, Issue 16
Published April 21, 2026
Pages 1182-1195
ISSN 0009-7322
Publisher Lippincott Williams & Wilkins

Journal Info

Circulation

Lippincott Williams & Wilkins

ISSN: 0009-7322 Health Sciences

Authors (87)

T

Thomas M. Glenn

Pediatrics and Cardiology, Baylor College of Medicine and Texas Children’s Hospital, Houston (T.M.G., S.J.D.).

N

Nadine A. Kasparian

S

Shahnawaz Amdani

D

David Renaud

Department of Child and Adolescent Health, Division of Pediatrics III–Cardiology, Pulmonology, Allergology and Cystic Fibrosis, Medical University of Innsbruck, Austria (D.R.).

M

Michael V. DiMaria

Pediatrics and Cardiology, C.S. Mott Children’s Hospital, University of Michigan, Ann Arbor (M.V.D., K.R.S.; M.V.D. now with HCA HealthONE Rocky Mountain Children’s at Presbyterian St. Luke’s, Denver, CO).

J

Jennifer Teh

Heart Institute (J. Teh, N.A.P.), Children’s Hospital Los Angeles, CA.

D

David M. Leone

Heart Institute (N.A.K., D.M.L., R.V., J. Theobald, J.B.A., A.R.O.)

A

Arjun K. Mahendran

Pediatrics, Texas Center for Pediatric and Congenital Heart Disease, Dell Medical School at The University of Texas at Austin/Dell Children’s Medical Center (A.K.M.).

N

Nancy A. Pike

Heart Institute (J. Teh, N.A.P.), Children’s Hospital Los Angeles, CA.

S

Stephen J. Dolgner

Pediatrics and Cardiology, Baylor College of Medicine and Texas Children’s Hospital, Houston (T.M.G., S.J.D.).

A

Andrew L. Cheng

Pediatrics and Cardiology (A.L.C.), Children’s Hospital Los Angeles, CA.

R

Rahul H. Rathod

S

Sumeet S. Vaikunth

Internal Medicine and Pediatrics, Hospital of the University of Pennsylvania, Philadelphia (S.S.V.).

S

Surendranath R. Veeram Reddy

Pediatrics and Cardiology, Children’s Health, UT Southwestern, Dallas, TX (S.R.V.R.).

R

Rohith Vanam

Heart Institute (N.A.K., D.M.L., R.V., J. Theobald, J.B.A., A.R.O.)

J

Jeff Theobald

Heart Institute (N.A.K., D.M.L., R.V., J. Theobald, J.B.A., A.R.O.)

K

Kurt R. Schumacher

Pediatrics and Cardiology, C.S. Mott Children’s Hospital, University of Michigan, Ann Arbor (M.V.D., K.R.S.; M.V.D. now with HCA HealthONE Rocky Mountain Children’s at Presbyterian St. Luke’s, Denver, CO).

S

Sarah A. Hummel

J

Jennifer Conway

D

David J. Goldberg

Pediatrics (D.J.G.), Children’s Hospital of Philadelphia, PA.

D

Dala Zakaria

Pediatrics and Cardiology, Arkansas Children’s Hospital, Little Rock (D.Z.).

S

Sarah B. Clauss

Pediatrics and Cardiology, Children’s National Hospital, Washington, DC (S.B.C.).

D

Divya Suthar

Pediatrics and Cardiology, Children’s Healthcare of Atlanta, GA (D.S.).

R

Roni M. Jacobsen

Pediatrics and Cardiology, Children’s Hospital Colorado, Aurora (R.M.J.).

E

Evonne M. Morell

Pediatrics and Cardiology, Children’s Hospital of Pittsburgh of UPMC, PA (E.M.M., T.A.; T.A. now with Pediatrics and Cardiology, Children’s Health, UT Southwestern, Dallas, TX).

J

John C. Dykes

Pediatrics and Cardiology, Lucile Packard Children’s Hospital, Stanford University, Palo Alto, CA (J.C.D.).

A

Angela J. Weingarten

Medicine and Pediatrics, Divisions of Cardiovascular Medicine and Pediatric Cardiology, Monroe Carrell Jr Children’s Hospital, Vanderbilt University Medical Center, Nashville, TN (A.J.W.).

D

Deepti P. Bhat

Pediatrics and Cardiology, Phoenix Children’s Hospital, AZ (D.P.B.).

B

Benjamin E. Reinking

Pediatrics and Cardiology, University of Iowa Stead Children’s Hospital, Iowa City (B.E.R.).

T

Tarek Alsaied

C

Carole Lannon

James M. Anderson Center for Health Systems Excellence (C.L.)

K

Kiona Y. Allen

Pediatrics and Cardiology, Ann & Robert H. Lurie Children’s Hospital of Chicago, Northwestern Feinberg School of Medicine, Chicago, IL (K.Y.A.).

J

Jeff B. Anderson

Heart Institute (N.A.K., D.M.L., R.V., J. Theobald, J.B.A., A.R.O.)

L

Lacie B. Patterson

Sisters by Heart, Valley Center, CA (L.B.P.).

D

David W. Brown

Pediatrics and Cardiology, Boston Children’s Hospital, MA (R.H.R., D.W.B.).

R

Richard James

Medical Education, Library Services, Nemours Children’s Health, Wilmington, DE (R.J.).

J

Jack Rychik

Cardiology (D.J.G., J.R.), Children’s Hospital of Philadelphia, PA.

A

Alexander R. Opotowsky

Heart Institute (N.A.K., D.M.L., R.V., J. Theobald, J.B.A., A.R.O.)

J

Jeremy T. Affolter

D

Diane Aguero

A

Alaa Aljiffry

S

Saleem Almasarweh

J

Julie Bonn

J

Jamie N. Colombo

P

Paul Critser

M

Meghan A. Didier

K

Kathryn M. Dodds

F

Francine Erenberg

D

David M. Finkelstein

T

Therese M. Giglia

S

Salil Ginde

M

Molly Gord

J

Joseph N. Graziano

J

Jessica Haley

S

Stephanie S. Handler

J

Jesse Hansen

A

Anyir Hsieh

A

Alicia K. Hutson

N

Natalie M. Jayaram

O

Omar M. Khalid

M

Matthew S. Lemler

A

Andrew S. Mackie

A

Amanda McCormick

K

Kimberly L. Moore

L

Lakshmi Nagaraju

M

Melanie Parent

T

Trudy Pierick

M

Michelle S. Ploutz

P

Pierangelo Renella

K

Kate Robb

N

Nancy Rudd

I

Ilana Schwartz

K

Kavisha M. Shah

R

Rachel J. Shustak

J

Jose Silva Sepulveda

M

Megan Soohoo

E

Eileen Stewart

M

Michelle M. Steltzer

S

Sherzana Sunderji

K

Karen M. Texter

R

Rocky Tsang

C

Casey Vogel

J

Jodie K. Votava-Smith

J

Justin Weigand

A

Alicia N. Wilmoth

F

Fred Wu

A

Adel K. Younoszai