Incidence and factors influencing the spontaneous closure of Fontan fenestration

Introduction: The Fontan operation is the final stage of single ventricle palliation in patients with complex congenital heart disease. Fenestration in the Fontan conduit, providing an atrial level right to left shunt, has been shown to reduce early postoperative morbidity. However, there is limited data on the long-term fate of this fenestration. The aim of this study is to define the rate of spontaneous closure of the fenestration in the Fontan conduit and factors predictive of the fate of the fenestration. Methods: This was a retrospective study reviewing the medical records of the patients who underwent fenestrated Fontan operation at our center. Preoperative, intraoperative and postoperative variables including the status of the Fontan fenestration were extracted and analyzed. Results: Of 67 patients included in the study, 15 (22%) had spontaneous closure of the fenestration. Of the remaining 52 patients, 11 (20%) had procedural closure of this fenestration (10 via cardiac catheterization and 1 via surgery) at a median duration of 3 months after the Fontan operation. Patients with higher preoperative pulmonary vascular resistance and a history of postoperative systemic venous thromboembolism had higher likelihood of having persistence of the fenestration with P value of.045 and.037, respectively. Conclusions: The rate of spontaneous closure of the Fontan fenestration was 22% in our study. Elevated preoperative pulmonary vascular resistance and history of systemic venous thromboembolism are predictive of persistent Fontan fenestration.