Fontan pathway diameter in adults undergoing exercise catheterization: Association with hemodynamics, exercise capacity, and liver scores

Authors

• Jacob Y. Cao, Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minn; Department of Cardiology, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia; Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia.
• Alexander C. Egbe, Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minn.
• C Charles Jain, Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minn.
• Christopher Francois, Department of Radiology, Mayo Clinic, Rochester, Minn.
• Patrick S. Kamath, Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minn.
• Yves D'Udekem, Division of Cardiac Surgery, Children's National Heart Institute, The George Washington University School of Medicine and Health Sciences, Children's National Hospital, Washington, DC.
• David Celermajer, Department of Cardiology, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia; Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia.
• Rachael Cordina, Department of Cardiology, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia; Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia.
• William R. Miranda, Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minn. Electronic address: [email protected].

Document Type

Journal Article

Publication Date

3-2-2026

Journal

The Journal of thoracic and cardiovascular surgery

DOI

10.1016/j.jtcvs.2026.02.027

Keywords

Fontan circulation; Fontan pathway size; exercise capacity; invasive hemodynamic assessment; liver disease

Abstract

OBJECTIVES: The Fontan pathway (inferior vena cava-pulmonary artery connection) regulates forward flow and backward pressure, but its optimal size remains uncertain. This study aimed to evaluate the relationship between Fontan pathway diameter, hemodynamics, exercise capacity, and liver disease markers. METHODS: A retrospective review of 67 adults with extracardiac conduit (EC) or lateral tunnel (LT) Fontan procedures who underwent exercise cardiac catheterization was conducted. Minimal pathway diameter was measured via angiography or computed tomography. Exercise capacity was assessed by percent predicted peak oxygen consumption. Liver disease markers included aspartate aminotransferase-to-platelet ratio, fibrosis-4, and Model for End-Stage Liver Disease excluding international normalized ratio scores. RESULTS: The mean age at catheterization was 30.4 ± 7.9 years. Minimal pathway diameter was 17.5 ± 6.0 mm. Larger diameter was associated with reduced augmentation of pulmonary and systemic blood flow during exercise (pulmonary flow, -2.3% per mm; 95% CI, -3.9 to -0.7; P = .005; systemic flow, -2.2% per mm; 95% CI, -4.1 to -0.2; P = .03), and lower percent predicted peak oxygen consumption (-0.8% per mm; 95% CI, -1.4 to -0.2; P = .009), independent of exercise mean pulmonary artery and pulmonary artery wedge pressures, and peak heart rate. No consistent association was observed between pathway diameter and markers of liver disease. Notably, the pressure gradient on the liver imposed by the pathway contributed minimally to inferior vena cava pressure at rest (0; interquartile range, 0-7.1%) or during exercise (6.4%; interquartile range, 0.5%-14.3%). CONCLUSIONS: Larger Fontan pathway diameter was paradoxically associated with impaired flow augmentation during exercise, which may contribute to reduced exercise capacity.

APA Citation

Cao, Jacob Y.; Egbe, Alexander C.; Jain, C Charles; Francois, Christopher; Kamath, Patrick S.; D'Udekem, Yves; Celermajer, David; Cordina, Rachael; and Miranda, William R., "Fontan pathway diameter in adults undergoing exercise catheterization: Association with hemodynamics, exercise capacity, and liver scores" (2026). GW Authored Works. Paper 8947.
https://hsrc.himmelfarb.gwu.edu/gwhpubs/8947

Department

Surgery