Evaluating the Longevity of the Fontan Pathway

Abstract

Children born with single ventricle physiology who undergo Fontan palliation face a diverse set of long-term complications. However, patient follow-up has in large part been limited to single institutional experiences without uniform application of diagnostic modalities to screen for relevant outcomes. Additionally, the use of different graft materials and variable surgical technique as part of the Fontan procedure has further complicated the evaluation of single ventricle patients. The purpose of this review is to define the changes in the Fontan pathway specific to the graft material used and its relationship to patient outcomes. As a means of introduction, we briefly review the historical evolution of the Fontan procedure with a focus on the intent behind design changes and incorporation of different biomaterials. We further delineate changes to the Fontan pathway which include the development of stenosis, differential growth, thrombosis, and calcification. Ultimately, the recognition of the changes noted within the Fontan pathway need to be assessed relative to their impact on patient hemodynamics, functional capacity, and Fontan-associated comorbidities.

Keywords: Calcification; Fontan; Stenosis; Thrombosis.

Fig. 1

Variability in conduit stenosis of ePTFE EC Fontan. a demonstrates long segment narrowing compared to b demonstrating anastomotic stricture. Use of figure courtesy of Congenital Heart Disease. Originally published by Hagler et al. [13]

Fig. 2

Axial contrast-enhanced CT image with thrombosis within the Fontan conduit and bilateral pulmonary embolus. Use of figure courtesy of the Radiological Society of North American. Original published by Fredenburg et al. [12]

Fig. 3

Axial and coronal CT images demonstrating calcification along the entire length of the Fontan graft. Use of the figure courtesy of Elsevier Press. Originally published by Hayabuchi et al. [58]