[II-JCKAP4-2] Impact of Optimal Fenestration Size on Outcomes of High-Risk Fontan Patients
Background: We aimed to analyze mid-term outcomes of the fenestrated Fontan procedure, focusing on the fenestration size.Methods: We retrospectively reviewed the outcomes of the fenestrated Fontan procedure. Among 165 patients who underwent the Fontan procedure, fenestration was created in 27 patients with the highest risks, including those with hypoplastic left heart syndrome, hypoplastic pulmonary arteries, heterotaxy syndrome with high pulmonary vascular resistance, and pulmonary arterial pressure >15mmHg. The patients underwent the procedure at a median age of 3years (body weight, 11.4kg; body surface area (BSA), 0.54m2). Fenestration sizes were 3.5 to 5mm.Results: Spontaneous fenestration closure occurred within 1year postoperatively in nine patients. Among them, three experienced Fontan failure, necessitating re-fenestration. The size corrected by BSA at the time of surgery was smaller in patients with fenestration closure (6.4mm/m2 vs. 8.3mm/m2, p<0.05). Patients with a fenestration >9mm/m2 were more likely to show severe desaturation and require home oxygen therapy following discharge.Conclusions: Spontaneous fenestration closure affected the frequency of Fontan complications. A very small fenestration size corrected by BSA was a significant risk factor for spontaneous closure. Conversely, a very large fenestration size corrected by BSA resulted in severe desaturation. The optimal fenestration size to prevent early spontaneous closure and severe desaturation is approximately 8mm/m2.