Prospective observational study comparing the outcomes of fenestrated and non-fenestrated extracardiac Fontan...

Fenestration in the Fontan procedure was introduced to improve early postoperative outcomes by reducing systemic venous pressure and augmenting preload to the systemic ventricle. It is believed to decrease pleural drainage, shorten hospital stay, and reduce complications. However, fenestration may result in systemic desaturation and carries a potential risk of paradoxical thromboembolism. The benefits of routine fenestration remain controversial. This study aimed to evaluate whether adding a fenestration influences early postoperative outcomes.

Between March 2024 and November 2025, 52 patients underwent Fontan completion at our institution. Forty patients met the inclusion criteria and were prospectively divided into two equal groups: non-fenestrated (Group 1, n = 20) and fenestrated (Group 2, n = 20). Twelve patients were excluded due to a primary Fontan procedure, elevated pulmonary vascular resistance, increased transpulmonary gradient, or significant branch pulmonary artery distortion. Demographic and perioperative parameters, including ventilation duration, inotrope duration, chest drain duration and volume, ICU stay, and total hospital stay, were analysed.

Baseline demographic and intraoperative variables were comparable between groups. Duration of mechanical ventilation, ICU stay, total chest drainage, and cardiopulmonary bypass time were similar. Chest drain duration was shorter in the fenestrated group (8.1 ± 4.2 vs. 10.2 ± 5.3 days), but this difference was not statistically significant (p = 0.173). Discharge oxygen saturation was significantly lower in the fenestrated group (88.9 ± 5.6% vs. 93.3 ± 3.5%; p = 0.0072).

In the present cohort, fenestration was not associated with a statistically significant improvement in most early perioperative outcomes. Larger studies are needed to define its role.