Novel technique to reduce the size of a Fontan Diabolo stent fenestration

To develop an effective catheter technique to reduce the size of a Diabolo stent fenestration in the failing Fontan circulation.

Diabolo stent fenestration is employed by many centers in the treatment of the failing Fontan patient. With subsequent recovery, exercise tolerance may be impaired by significant desaturation secondary to the right to left shunt across the fenestration. Complete fenestration closure carries the risk of recurrence of the initial symptoms and, hence, reduction of the size of fenestration should be the preferred technique.

Twenty-eight patients with failing Fontan circulations (16 early and 12 late) underwent Diabolo stent fenestration for relief of symptoms. Five of these patients remained very limited by severe desaturation even at rest, after complete recovery from symptoms. Further cardiac catheterization with crimping/reduction of the size of the waist of the stent was carried out using a technique whereby a snare catheter was placed over the waist of the stent aided by an arterio-venous guidewire loop and a balloon catheter placed within the stent.

All 5 patients had successful stent reduction with improvement in saturations, whilst still maintaining a small residual fenestration. No complications were encountered.

This novel technique of reduction of a diabolo stent fenestration, in a failing Fontan circulation, offers the advantages of avoidance of implanting further devices in the circulation and the ability to redilate the stent should symptoms recur.