Assessment of liver T1 mapping in fontan patients and its correlation with magnetic resonance elastography-derived liver stiffness.

Objectives: To explore the utility of liver T1 mapping in Fontan patients and its correlation to magnetic resonance elastography (MRE)-derived liver stiffness.
Background and Aims: Liver disease is a major long-term extra cardiac complication in the Fontan population. MRE is frequently used to quantify liver stiffness in Fontan patients; however, it has certain limitations. Native T1 mapping by cardiac magnetic resonance (CMR) is useful in assessment of cardiac fibrosis, but its potential in evaluating liver fibrosis and its correlation to MRE-derived liver stiffness in Fontan patients have not been reported.
Methods: Fontan patients who underwent CMR and MRE were included. Liver Native T1, extracellular volume (ECV) and delta coefficients were measured and correlated with MRE-derived liver stiffness in all Fontan patients. Native liver T1 in Fontan patients were compared to normal controls with biventricular circulation and no known liver disease.
Results: A total of 17 Fontan patients and 7 normal controls were included in this study. Fontan patients had significantly higher liver native T1 (690 ± 41 ms vs 620 ± 35 ms; p < 0.001) as compared to controls. There was strong positive correlation between MRE derived liver stiffness and liver native T1 (r = 0.81, p < 0.001).
Conclusions: Liver native T1 was significantly elevated in Fontan patients compared to controls and strongly correlated with MRE-derived liver stiffness. This technique may prove to be a useful noninvasive imaging biomarker for assessing liver fibrosis in the Fontan population.