Microcirculatory Alterations and Endothelial Glycocalyx in Fontan Circulation: Association With Central Venous...

Fontan circulation is characterized by chronically elevated central venous pressure (CVP) and reduced cardiac output, which may adversely affect the systemic microcirculation. We investigated whether Fontan circulation is associated with alterations of the endothelial glycocalyx.

Forty-four patients with congenital heart disease undergoing postoperative endothelial glycocalyx evaluation were included. The perfused boundary region (PBR), an inverse indicator of glycocalyx dimensions, was measured noninvasively using GlycoCheck. PBR was compared between patients with Fontan and biventricular circulation, and its relationship with CVP was evaluated.

Fourteen patients had Fontan circulation, including three with bidirectional Glenn circulation, and 30 had biventricular circulation. PBR was significantly higher in patients with Fontan circulation than in those with biventricular circulation (2.07 ± 0.15 vs. 1.72 ± 0.17 μm, p < 0.0001). CVP was also significantly higher in the Fontan group (13.0 ± 2.2 vs. 7.1 ± 2.8 mmHg, p < 0.0001). PBR was positively correlated with CVP (r = 0.58, p < 0.0001).

Fontan circulation is associated with an increased PBR, suggesting alterations of the endothelial glycocalyx. The association between PBR and CVP suggests that chronic venous hypertension may be associated with systemic microcirculatory alterations in Fontan circulation.