Fate of the Fontan connection: Mechanisms of stenosis and management

Abstract

Background: Stenosis of the venous connections and conduits is a well-known late complication of the Fontan procedure. Currently, data on the outcomes of percutaneous intervention for the treatment of extra- or intracardiac conduits and lateral tunnel baffles obstruction are limited. In an attempt to better define the nature and severity of the stenosis and the results of catheter interventional management, we reviewed Fontan patients with obstructed extra- or intracardiac conduits and lateral tunnel baffles.

Methods: Retrospective review of all Fontan patients who had cardiac catheterization from January 2002 to October 2018 was performed. Hemodynamic and angiographic data that assessed extra- or intracardiac conduit, or lateral tunnel baffle obstruction/stenosis were evaluated.

Results: Twenty patients underwent catheter intervention because of conduit stenosis, including calcified homografts, stenotic Gore-Tex conduits and obstructed lateral tunnels. Six other patients had Fontan obstruction but were referred for surgical revision. After stenting, there was a significant reduction in the connection gradient [2.0 mm Hg (IQR 2; 3) vs 0 mm Hg (IQR 0; 1), P < .0001]. Fontan conduit/connection diameter increased [10.5 mm (IQR 9; 12) vs 18 mm (IQR 14.9; 18); P < .0001] and New York Heart Association class [III (IQR II; III) vs I (IQR II; III); P = .03) with stent placement.

Conclusions: We demonstrated the hemodynamics and angiographic subtypes of conduit stenosis in patients after Fontan, We showed that calcified homografts, stenotic Gore-Tex conduits and lateral tunnels pathways can be safely and effectively stented to eliminate obstruction. Percutaneous stenting is associated with a decrease in connection gradients and improvement in functional capacity.

Keywords: cirrhosis; conduit; stenosis; stenting.

Figure 1

A, Shows lateral tunnel stenosis in a 26‐year‐old male with cirrhosis. The narrowing is approximately 13 mm in diameter. B, Illustrates the same lateral tunnel after placement of a 35‐cm length covered Cheatham Platinum stent. The final diameter is approximately 18 mm in diameter

Figure 2

A, B, Show anteroposterior and lateral images of a Gore‐Tex intracardiac conduit in a 31‐year‐old female patient with history of mitral atresia and presenting with congestive hepatopathy. The conduit is diffusely narrowed by most severely distally at 10‐11 mm. Also a previously placed occlusive device produces stenosis. C, Illustrates the significant conduit enlargement after placement of two 26 mm eV3 stents with an increase in size to 13.5 mm

Figure 3

A, Illustrates the calcific diffuse stenosis of a homograft conduit in a 24‐year‐old male. The 20‐mm homograft is now 13 mm in diameter. B, After placement of two 40 mm Palmaz stents the conduit is increased to 18 mm in diameter

Figure 4

Panel A illustrates a long diffusely narrowed Gore‐Tex ECC in an 18‐year‐old male with pulmonary atresia with intact ventricular septum. The conduit was 14 mm when placed 16 years earlier. B, Illustrates the enlargement of the Gore‐Tex conduit to 16‐17 mm after placement of two 4010 Palmaz stents

Figure 5

Anteriopostior (A) and lateral images (B) of an 18 mm Gore‐Tex conduit initially placed in a 3‐year‐old o male Fontan patient. At 23 years of age, severe stenoses to 11‐14 mm are present. The central conduit is also narrowed to 15 mm. The entire conduit was stented with 3 eV3 36 mm stents and dilated to 20 mm. The final stent diameter in the lower panels (C, D) is 19 mm

Figure 6

Anteroposterior (A) projection illustrating a 9.4 mm stenosis at the IVC anastomosis of an originally 18 mm homograft conduit. This was effectively dilated to 18 mm with a 34 mm covered CP stent (B). (C) Angiogram obtained in a 26‐year‐old patient with cirrhosis illustrates a severe focal stenosis at the PA anastomosis of a calcified 22 mm homograft conduit originally placed 21 years previously. It is also diffusely narrowed. It was dilated to 20 mm with a 55 mm long covered CP stent

Figure 7

Changes in Fontan IVC pathway diameter pre‐ and poststenting