Device Closure of Fontan Fenestrations

Abstract

Since the late 1980 s, essentially all Fontan operations at Children’s Hospital Boston have been done using a fenestrated technique. The rationale behind this modification is as follows: For a Fontan circulation to function properly, it is critical that the pulmonary vascular resistance be low and that the mean PA pressures also be low. In particular, it is desirable to have a mean PA pressure below 20 mmHg. Cardiopulmonary bypass invariably results in an increase in PVR in the immediate postoperative period. To increase cardiac output and possibly reduce the pressure in the Fontan pathway, a small hole is created in the Gore-Tex baffle that makes up part of the lateral tunnel. This fenestration is 4 mm in diameter and is directed anteriorly and leftward. It allows some of the systemic venous return to enter the systemic circulation (right-to-left shunt across the baffle) and bypass the lungs. This results in maintenance of forward cardiac output at the expense of oxygen saturation. The fenestration technique has resulted in a much more stable postoperative ICU course as well as a decreased incidence and duration of pleural effusion following Fontan surgery (1).