ORIGINAL ARTICLE Effects of Transcatheter Closure of Fontan Fenestration on Exercise Tolerance Tarek S. Momenah Æ Haifa Eltayb Æ Reida El Oakley Æ Howeida Al Qethamy Æ Yahya Al Faraidi Received: 14 July 2007 / Accepted: 26 October 2007 / Published online: 11 December 2007 Ó Springer Science+Business Media, LLC 2007 Abstract Baffle fenestration is associated with a signifi- cantly better outcome in standard and high-risk patients undergoing completion of Fontan. We report the effects of subsequent transcatheter closure of fenestration on exercise capacity and oxygen saturation. Sixteen patients with a mean age of 10.3 years underwent Amplatzer septal occluder (ASO) device transcatheter closure of Fontan fenestration. All had a fenestrated Fontan operation 6 month to 8 years prior to the procedure. A stress test was performed before and after device closure of fenestration in 14 patients (2 patients did not tolerate stress test before the procedure). The fenestrations in all patients were success- fully occluded with the use of the Amplatzer device occluder. No complications occurred during or after the procedure. O 2 saturation increased from a mean 85.1 ± 7.89% to 94.5 ± 3.63% (p \ 0.01) at rest and from 66.2 ± 12.86% to 87.2 ± 8.64% (p \ 0.01) following exercise. Exercise duration has also increased from 8.22 ± 2.74 min to 10.29 ± 1.91 min (p \ 0.05). Trans- catheter closure of Fontan fenestration increases the duration of exercise capacity and increases O 2 saturation at rest and after exercise. Keywords Fontan procedure Á Fenestration closure Á Transcatheter closure Introduction Three- to-six-millimeter fenestration of the Fontan is associated with better early survival and less perioperative complications after a Fontan operation [1, 2, 6]. This is attributed to the reduction of systemic venous pressure and to the augmentation of the systemic ventricular preload in the presence of high pulmonary artery pressure [1, 6, 8]. However, these short-term benefits come at the expense of systemic oxygen saturation and the potential hazards of right-to-left shunt such as endocarditis and paradoxical embolism, in the long term. Delayed postoperative trans- catheter closure of Fontan fenestration is considered an option to prevent such long-term sequelae [4, 9]. The effects of such a procedure on exercise duration and oxygen satu- ration at rest and following exercise are reported here. Materials and Methods Patient Population The study was approved by the Internal Review Board at the Prince Sultan Cardiac Centre. The mean age was 10.3 years (6–13 years) and a mean weight of 34.1 kg (15.6– 61.7 kg). All participated in the study 6 months to 8 years from the date of operation. The pre-operative diagnosis is summarized in Table 1. Patients had bidirectional Glenn shunts constructed 2–8 years before the completion of Fontan. The Fontan operation consisted of using direct bicaval cannulation and aortic return, keeping the heart perfused and beating while allowing mild systemic hypo- thermia. All existing aortopulmonary shunts were closed and the main pulmonary artery (MPA) was transected. The pulmonary artery confluence was enlarged with a bovine T. S. Momenah (&) Á H. Eltayb Á R. E. Oakley Á H. A. Qethamy Á Y. A. Faraidi Prince Sultan Cardiac Center, P.O. Box 7897, Riyadh 1159, Kingdom of Saudi Arabia e-mail: kidecho@yahoo.com 123 Pediatr Cardiol (2008) 29:585–588 DOI 10.1007/s00246-007-9154-3