Magnetic resonance quantification of regional blood flow and oxygen delivery to the brain, gut, kidneys, and lower extremities in adolescents with a Fontan circulation compared to biventricular controls

Sep 30, 2026

Uploaded by Hazel

Background: Progressive extracardiac disease is common in single-ventricle patients after Fontan palliation, but its mechanisms remain unclear. Limited flow reserve in the Fontan circulation may reduce oxygen and nutrient delivery to tissues. This study quantified regional flow volumes and oxygen delivery to key organs in children and adolescents with a Fontan circulation. Methods: In 17 Fontan subjects and 14 controls, MRI quantified arterial flow to major vessels and computed oxygen delivery from hemoglobin and pulse oximetry, comparing groups and correlating with exercise performance.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages7

Reading Time18 min

AccessFree to download

Short Communication

Introduction

Methods

Results

Conclusion

Journal of Cardiovascular Magnetic Resonance 27 (2025) 101907 Contents lists available at ScienceDirect Journal of Cardiovascular Magnetic Resonance journal [homepage:](homepage: www.sciencedirect.com/journal/joc mr)[ www.sciencedirect.com/journal/joc mr](homepage: www.sciencedirect.com/journal/joc mr) Short Communication Magnetic resonance quantification of regional blood flow and oxygen delivery to the brain, gut, kidneys, and lower extremities in adolescents with a Fontan circulation compared to biventricular controls Jennifer Romanowicza,⁎, Sungho Parkb, Jenifer Bunna, Roni M. Jacobsena, Brian Fonsecaa, Jenny E. Zablaha, Erin K. Englundb, Alex J. Barkerb,1, Jesse A. Davidsona,1 a Department of Pediatrics, Section of Cardiology, Children’s Hospital Colorado and University of Colorado Anschutz, 13123 E 16th Ave, Aurora, Colorado 80045, USA b Department of Radiology, Section of Pediatric Radiology, Children's Hospital Colorado, University of Colorado Anschutz, 13123 E 16th Ave, Aurora, Colorado 80045, USA A R T I C L E I N F O Keywords: Congenital heart disease Single ventricle Total cavopulmonary anastomosis MRI Peak VO2 Exercise performance A B S T R A C T Background: Accumulation of progressive extracardiac disease is nearly universal for patients with single ventricle heart disease palliated to a Fontan circulation; however, etiologies are poorly understood. Limited flow reserve in the Fontan circulation may underlie extracardiac disease found in Fontan physiology through reduced oxygen and nutrient delivery to the tissues. This study aimed to determine regional flow volumes and oxygen delivery to key organ systems in children and adolescents with a Fontan circulation. Methods: In 17 Fontan subjects and 14 biventricular controls, regional arterial flow volumes to the carotid, celiac, superior mesenteric, renal, and iliac arteries were quantified with magnetic resonance imaging. Arterial oxygen content was calculated using subject hemoglobin level and pulse oximetry, and regional oxygen delivery was calculated using regional flow volume and oxygen content for the above-listed arteries. Cardiac output was measured from ascending aorta flow, systemic blood flow from the caval veins, and aorto-pulmonary collateral flow was calculated as the difference between the two. Flows were compared between groups (t-test) and associations were analyzed between flows and with maximal exercise performance on clinical cardiopulmonary exercise testing (Pearson correlation). Results: On average, renal and iliac arterial flows were lower in the Fontan group, compared to controls. Carotid, celiac, and superior mesenteric arterial flows were preserved in the Fontan group. Arterial oxygen content was equivalent between groups, and thus, regional oxygen delivery followed the same pattern as regional flows. Cardiac output was no different between groups, but systemic blood flow was lower in Fontans due to loss offlow to aorto-pulmonary collaterals. Systemic blood flow correlated with iliac flow such that those with the lowest systemic flow had the least amount of iliac flow. Celiac arterial flow correlated with percent-predicted peak oxygen consumption on exercise testing. Conclusion: Our results are consistent with a limited flow reserve in the Fontan circulation with sacrifice of iliac arterial flow as global systemic blood flow decreases. Importantly, these data were measured with subjects supine and at rest. Future work requires the addition of exercise to determine how flow to specific organs is affected by increasing metabolic demand from the extremities. Abbreviations: CMR, cardiovascular magnetic resonance; CO, cardiac output; Qs, systemic blood flow; APC, aortopulmonary collateral; PC, phase contrast; BSA, body surface area; VO2, oxygen consumption; SMA, superior mesenteric artery; SVC, superior vena cava; IVC, inferior vena cava ⁎ Corresponding author. E-mail address: [jennifer.romanowicz@child

FAQs

How were regional blood flow volumes measured in the study?

Regional arterial flow volumes to the carotid, celiac, superior mesenteric, renal, and iliac arteries were quantified using magnetic resonance imaging in Fontan subjects and biventricular controls.

How was regional oxygen delivery calculated?

Arterial oxygen content was derived from each subject’s hemoglobin level and pulse oximetry, and regional oxygen delivery was calculated from regional flow volume and oxygen content for the target arteries.

What differences were found between the Fontan group and controls?

Renal and iliac arterial flows were lower in the Fontan group, while carotid, celiac, and superior mesenteric flows were preserved. Oxygen content was equivalent between groups, so oxygen delivery followed the same flow pattern.

Sep 30, 2026

Uploaded by Hazel