End-organ injury in patients with a Fontan circulation
End-organ injury in patients with a Fontan circulation
A small but important proportion of children born in the Netherlands are born with a functionally univentricular heart. These hearts are characterized by chronic volume overload of the functioning ventricle and cyanosis. Many of the children born with a functionally univentricular heart undergo a series of operations resulting in a Fontan circulation, in which the caval veins are directly connected to the pulmonary arteriess. The introduction of the Fontan circulation has greatly improved the survival of children born with a functionally univentricular heart. However, this circulation gradually deteriorates over time, resulting in reduced organ perfusion and eventually organ failure. This progressive decline is known as Fontan failure. This thesis of Gaston van Hassel investigated the long-term effects of the Fontan circulation on the lungs, liver, blood, and kidneys.
The main findings of this thesis showed that pulmonary restriction occurs in one-third of Fontan patients. Lower FVC was associated with reduced exercise capacity and FVC declined more rapidly with age than in the general population. No association was found between liver abnormalities on MRI and clinical outcomes, raising questions about the need for intensive liver surveillance. In addition, iron deficiency and kidney dysfunction were common. Iron deficiency without anemia was associated with poorer exercise tolerance. Kidney function declined more rapidly than in the general population, and worsening kidney function was associated with a higher risk of mortality.
By characterizing the multiorgan manifestations of the Fontan circulation on different organs, this thesis provides insights for more targeted treatment and monitoring of patients with a Fontan circulation.