Spectrum of Fontan-associated liver disease assessed by MRI and US in young adolescents

Abstract

Purpose Patients with Fontan circulation are at risk of developing hepatic fibrosis/cirrhosis. The mechanisms and disease development are unclear and early secondary liver cancer is a concern. This study will describe hepatic imaging findings in a national cohort of adolescents with Fontan circulation. Methods The patients prospectively underwent abdominal contrast enhanced magnetic resonance imaging (MRI) including diffusion-weighted imaging. Images were assessed for criteria of fibrosis/cirrhosis including characterization of hepatic nodules. These nodules were in addition, assessed by ultrasonography (US). Nodules ≥ 1 cm were investigated and monitored to evaluate malignant transformation. Clinical and hepatic serological data were recorded. Results Forty-six patients, median age of 16.5 years (15.4–17.9 years) were enrolled. All patients underwent US examination and MRI was performed in 35/46 patients. On MRI, 60% had hepatomegaly and 37% had signs of fibrosis/cirrhosis. Seven patients had together 13 nodules ≥ 1 cm in diameter. Only 4/13 (17%) where seen on US. Nodules had variable MRI signal characteristics including hepatobiliary contrast enhancement and two nodules revealed portal venous phase ‘wash-out’ on the first examination. No further imaging signs of malignancy were revealed during the follow-up period of median 24.4 (7–42) months. Conclusion The majority of adolescents with Fontan circulation had imaging findings of fibrosis/cirrhosis of varying severity. US had low detection rate of hepatic nodules compared to MRI. The imaging work-up before transition to adult cardiology care did not reveal findings suggestive of malignancy. However, the high prevalence of Fontan-associated liver disease calls for surveillance strategies even in childhood.

Semiquantitative characterization of dynamic magnetic resonance perfusion of the liver in pediatric Fontan patients

“…However, it is in contrast to the findings of Thrane et al [32], where only 28.6% of patients showed heterogeneous contrast enhancement on MRI. The low incidence of abnormal contrast enhancement in the study of Thrane et al [32] may be related to the injection of contrast medium for time-resolved angiography before dynamic liver MRI so, by the time of the dynamic liver MRI, there may already have been some equilibrium phase hepatic enhancement obscuring reticular hypoenhancement. The fact that all enhancement abnormalities in our study eventually became isointense to surrounding liver parenchyma on successive dynamic images supports the theory that these areas of hypoenhancement are related to delayed perfusion of parenchyma surrounding the small hepatic veins, similar to a Budd-Chiari-type phenomenon.…”

“…Our findings are in line with previous studies showing abnormal liver enhancement in most patients with Fontan palliation and in patients with other causes of congestive hepatopathy [29,31]. However, it is in contrast to the findings of Thrane et al [32], where only 28.6% of patients showed heterogeneous contrast enhancement on MRI. The low incidence of abnormal contrast enhancement in the study of Thrane et al [32] may be related to the injection of contrast medium for time-resolved angiography before dynamic liver MRI so, by the time of the dynamic liver MRI, there may already have been some equilibrium phase hepatic enhancement obscuring reticular hypoenhancement.…”

Fontan‐associated liver disease

“…Another study of 35 patients, US detected only 17% of nodules that were found at MRI. [96,108,109] Cross-sectional F I G U R E 4 A 20-year-old female with complex congenital heart disease who had undergone the Fontan procedure. MRI images showing heterogeneous texture of the liver and heterogeneous enhancement due to congestive changes from the Fontan circulation.…”

“…Another study of 35 patients, US detected only 17% of nodules that were found at MRI. [ 96,108,109 ] Cross‐sectional imaging, particularly MRI, has the additional advantage of better characterizing nodules for guiding further management.…”

Fontan-Associated Liver Disease: Pathophysiology, Staging, and Management

“…Liver nodules are frequently detected in patients with FALD. 39,43,55,[65][66][67][68][69] In the only prospective study conducted to date, the prevalence of hepatic nodules was as high as 50%, and they were usually small (< 2 cm), multiple, and located in the periphery of the liver. 40 Postmortem series and biopsy studies have shown that most of these lesions correspond to focal nodular hyperplasia (FNH) or benign regenerative nodules.…”