Arrhythmia after cone repair for Ebstein anomaly: The Mayo Clinic experience in 143 young patients

Background: The increased incidence of preoperative and postoperative arrhythmia in Ebstein anomaly (EA) prompted some clinicians to perform an electrophysiology study (EPS) in all patients prior to surgery for EA. The cone repair (CR) is the current surgical option of choice for most young patients with EA but the effect of the CR on arrhythmia is not well established. Objectives: To assess the burden of arrhythmia in young patients after CR and to assess the utility of selective preoperative EPS. Materials and Methods: A retrospective review of all patients <21 years of age with EA who had a CR at Mayo Clinic from June 2007 to December 2015 was performed. Surveys were mailed and telephone calls were made to all individuals to assess antiarrhythmic medication use and EP/device procedures performed after CR. Results: There were 143 patients; median age, 10 years (0.1–20.9 years). Thirty-five (24%) patients had a preoperative EPS of which 26 (18%) had a preoperative ablation. Indications for EPS were Wolff–Parkinson–White (WPW), documented arrhythmia, or suspected arrhythmia. Posthospital discharge data were available for 140 (98%) patients. Mean follow-up was 2.9 years (0.1–9.2 years). At follow-up, 7 (5%) patients were receiving antiarrhythmic medications. After CR, only 3 (2%) patients who did not have a preoperative EPS have required an ablation. Conclusions: The risk of arrhythmia after CR for EA in young patients is very low when a preoperative EPS is limited to those with WPW, known arrhythmia, or suspected arrhythmia. In smaller patients, it may be reasonable to defer the EPS.