Due to lack of enrollment this study was permanatly closed March 2022. The incidence of FONTAN patients being referred for liver biospsies and occurance of COVID effected participants enrolled.

In this research study, the investigators will conduct a prospective cross-sectional study of pediatric and adult Fontan patients that will correlate a variety of quantitative MRI biomarkers with histopathologic data.

The purpose of this study is to develop noninvasive MRI methods for detecting, discriminating, and measuring liver fibrosis and congestion in the adolescent and adult Fontan population by correlating quantitative imaging measurements with histopathologic data, using a cross-sectional approach.

Over 5 years, approximately 40 pediatric and adult subjects (approximately 8 subjects per year) undergoing clinically-indicated liver biopsy for the evaluation of either 1) focal liver lesions/masses, or 2) suspected liver fibrosis/parenchymal disease will be recruited to participate in this study. Subjects will undergo research MR imaging within ±2 weeks of the liver biopsy procedure. A variety of MRI biomarkers will be correlated with histopathologic data obtained from the clinically indicated liver biopsy.

Inclusion Criteria:

• Single ventricle physiology congenital heart disease status post Fontan palliation
• Undergoing clinically-indicated liver biopsy
• Ability to tolerate 60 minutes in an MRI scanner without sedation

Exclusion Criteria:

• Known contraindication to MR imaging (e.g., implanted non-MRI compatible device)
• Known or suspected pregnancy. Female subjects of child bearing potential will undergo urine pregnancy testing prior to imaging

Eligible subjects will be identified through Cincinnati Children's Hospital Medical Center's (CCHMC) cardiology or hepatology clinics, or through CCHMCs Fontan Management Program