Related Experiment Video
Updated: Oct 13, 2025
A Model of Reverse Vascular Remodeling in Pulmonary Hypertension Due to Left Heart Disease by Aortic Debanding in Rats
Published on: March 1, 2022
Adverse fibrosis remodeling and aortopulmonary collateral flow are associated with poor Fontan outcomes
Andrea Pisesky1, Marjolein J E Reichert2, Charlotte de Lange3,4
1Department of Paediatrics, Division of Cardiology, The Hospital for Sick Children, University of Toronto, Labatt Family Heart Center, 555 University Avenue, Toronto, ON, M5G 1X8, Canada. andrea.pisesky@sickkids.ca.
Insights
Pediatric Fontan patients show significant cardiac remodeling, including ventricular dysfunction and fibrosis. Increased aortopulmonary collateral flow is linked to worse outcomes, highlighting the need for closer monitoring in these patients.
Area of Science:
- Cardiology
- Pediatric Cardiology
- Cardiovascular Imaging
Background:
- Cardiac remodeling is a significant concern in Fontan patients, but its extent and implications remain unclear.
- This study investigates cardiac function, fibrosis, and hemodynamics in young Fontan patients using cardiovascular magnetic resonance (CMR) imaging.
Purpose of the Study:
- To assess cardiac remodeling, function, and fibrosis in pediatric Fontan patients compared to healthy controls.
- To identify factors associated with adverse cardiac remodeling and clinical outcomes in Fontan survivors.
Main Methods:
- A retrospective cohort study comparing 55 Fontan patients with 44 healthy controls using cardiovascular magnetic resonance (CMR).
- Analysis included ventricular volumes, ejection fraction (EF), strain (circumferential, radial, longitudinal), extracellular volume fraction (ECV), and native T1 values.
- Correlations were examined between cardiac parameters, surgical variables (bypass, cross-clamp, circulatory arrest times), and aortopulmonary collateral (APC) flow.
Main Results:
- Fontan patients exhibited enlarged ventricles (EDVI), reduced EF, and impaired strain compared to controls.
- Increased ECV and native T1 values in Fontan patients indicate myocardial fibrosis.
- Longer bypass and cross-clamp times correlated with worse EF and strain.
- APC flow was independently associated with adverse composite outcomes (readmission, reintervention, failure, arrhythmia).
Conclusions:
- Pediatric Fontan patients demonstrate ventricular dysfunction, altered mechanics, and fibrotic remodeling.
- Cumulative exposure to cardiopulmonary bypass and increased APC flow are linked to myocardial dysfunction and fibrosis.
- Cardiac dysfunction, fibrosis, and APC flow are associated with adverse clinical outcomes in Fontan survivors.
Background:
The extent and significance in of cardiac remodeling in Fontan patients are unclear and were the subject of this study.
Methods:
This retrospective cohort study compared cardiovascular magnetic resonance (CMR) imaging markers of cardiac function, myocardial fibrosis, and hemodynamics in young Fontan patients to controls.
Results:
Fifty-five Fontan patients and 44 healthy controls were included (median age 14 years (range 7-17 years) vs 13 years (range 4-14 years), p = 0.057). Fontan patients had a higher indexed end-diastolic ventricular volume (EDVI 129 ml/m2 vs 93 ml/m2, p < 0.001), and lower ejection fraction (EF 45% vs 58%, p < 0.001), circumferential (CS - 23.5% vs - 30.8%, p < 0.001), radial (6.4% vs 8.2%, p < 0.001), and longitudinal strain (- 13.3% vs - 24.8%, p < 0.001). Compared to healthy controls, Fontan patients had higher extracellular volume fraction (ECV) (26.3% vs 20.6%, p < 0.001) and native T1 (1041 ms vs 986 ms, p < 0.001). Patients with a dominant right ventricle demonstrated larger ventricles (EDVI 146 ml/m2 vs 120 ml/m2, p = 0.03), lower EF (41% vs 47%, p = 0.008), worse CS (- 20.1% vs - 25.6%, p = 0.003), and a trend towards higher ECV (28.3% versus 24.1%, p = 0.09). Worse EF and CS correlated with longer cumulative bypass (R = - 0.36, p = 0.003 and R = 0.46, p < 0.001), cross-clamp (R = - 0.41, p = 0.001 and R = 0.40, p = 0.003) and circulatory arrest times (R = - 0.42, p < 0.001 and R = 0.27, p = 0.03). T1 correlated with aortopulmonary collateral (APC) flow (R = 0.36, p = 0.009) which, in the linear regression model, was independent of ventricular morphology (p = 0.9) and EDVI (p = 0.2). The composite outcome (cardiac readmission, cardiac reintervention, Fontan failure or any clinically significant arrhythmia) was associated with increased native T1 (1063 ms vs 1026 ms, p = 0.029) and EDVI (146 ml/m2 vs 118 ml/m2, p = 0.013), as well as decreased EF (42% vs 46%, p = 0.045) and worse CS (- 22% vs - 25%, p = 0.029). APC flow (HR 5.5 CI 1.9-16.2, p = 0.002) was independently associated with the composite outcome, independent of ventricular morphology (HR 0.71 CI 0.30-1.69 p = 0.44) and T1 (HR1.006 CI 1.0-1.13, p = 0.07).
Conclusions:
Pediatric Fontan patients have ventricular dysfunction, altered myocardial mechanics and increased fibrotic remodeling. Cumulative exposure to cardiopulmonary bypass and increased aortopulmonary collateral flow are associated with myocardial dysfunction and fibrosis. Cardiac dysfunction, fibrosis, and collateral flow are associated with adverse outcomes.
More Related Videos
06:29Wireless Telemetry Device Implantation in a Fontan Ovine Model for Continuous and Long-Term Hemodynamic Monitoring
Published on: May 2, 2025
12:45Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
Related Concept Videos
01:29Heart Failure II: Pathophysiology
01:15Aortic Regurgitation I: Introduction
01:22Mitral Stenosis I: Introduction
01:23Rheumatic Heart Disease I: Introduction
01:17Aortic Regurgitation IV: Nursing Management
01:25Aortic Regurgitation III: Medical Management