Abstract 17918: Using Cardiac MRI to Evaluate Liver Disease in Adult Fontan Patients: What Can We Learn?
Background: The extent of hepatic dysfunction in adults with a Fontan repair is poorly characterized. Evaluation of Fontan anatomy with cardiac magnetic resonance (CMR) can provide an opportunity to assess the liver and detect unrecognized abnormalities. We assessed the hypothesis that CMR would detect sub-clinical hepatic disease in adult patients with a Fontan.
Methods: A retrospective review of all adult patients with a Fontan at our Center who underwent CMR was performed. Clinical data, CBC, liver function tests (LFTs) and ultrasound (US) findings were recorded. Linear hepatic dimensions, IVC and right hepatic vein (RHV) size were assessed on CMR and compared to controls without hepatic or right-sided cardiac disease. Severity of hepatic congestion was evaluated by a radiologist with expertise in hepatic imaging using post-gadolinium images and graded from 1 to 4.
Results: Forty-two adults (57% male) with a Fontan underwent CMR, and 15 underwent abdominal US. Nineteen patients (45%) had a classic RA-PA Fontan and 23 (55%) had a lateral tunnel. Mean age of Fontan was 8.2 years. Mean age at the time of CMR was 28.3 years.
Hepatic congestion was assessed in 34 patients (81%) with a Fontan. Thirty-three (97%) had evidence of at least mild congestion on CMR while only 40% of patients had abnormalities on US. Moderate or severe congestion (grade 3 and 4) was present in 11 patients (32%). Elevated ALT and AST were present in 18 of 34 patients (45%) and were associated with moderate or severe hepatic congestion on CMR (p=0.004).
Patients with a Fontan had larger lateral to medial linear dimensions (204 mm vs. 169 mm, p=0.00), and larger RHV diameters (13 mm vs. 9 mm, p=0.00) than controls. RA-PA Fontan was associated with larger RHV diameters (15 mm vs. 11 mm, p=0.0004) than the lateral tunnel Fontan, but did not differ significantly in terms of hepatic congestion, liver size, or LFTs.
Conclusion: CMR appears to be more sensitive than laboratory studies or abdominal ultrasound in detecting sub-clinical liver disease and enlargement in adult Fontan patients. Extending the MRA field to include hepatic imaging during CMR of adult Fontan patients should be considered as a cost effective method to detect early liver disease in this population.
- © 2013 by American Heart Association, Inc.