In their prior works the investigators could show that there is evidence of a proinflammatory condition in a certain subgroup of patients with complex congenital heart disease and a so called Fontan circulation. Those patients are also prone to develop hepatic and myocardial fibrosis as well as to reveal collateral vessel formation. The investigators' hypothesis is that this pro-inflammatory condition is not only reflecting pre-stages of one or more of those 3 issues, but that this is also a main driving mechanism to develop and hepatic or myocardial fibrosis and collateral vessels.~The objective of the here proposed study thus is to identify the mechanisms that promote hepatic and myocardial fibrosis, and collateral vessel formation, and thus provide insight into the determination of those Fontan patients that tend to develop those conditions. The investigators attempt to link the issues of hepatic and myocardial fibrosis and collateral vessel formation by directing our focus on the phospholipid, amino acid and bile acid metabolism and on cell surface markers, cytokines, and chemokines as surrogates for proinflammatory, profibrotic and proangiogenic conditions.~This study would thereby allow for a deeper insight into Fontan pathophysiology and sequelae and might provide first steps towards the identification of possible diagnostic or eventually therapeutic targets.
Out objective is to identify the mechanisms that promote hepatic and myocardial fibrosis, and collateral vessel formation in patients with complex congenital heart disease and Fontan circulation.