Two-dimensional and 3D TEE can better define the anatomy and function of the tricuspid valve before surgery and provide valuable information in planning surgical repair. 3. Approximately one third of adults with Ebstein anomaly and ventricular preexcitation have multiple accessory pathways, associated with a high risk of SCD. Adults with Ebstein anomaly also have a high prevalence of atrial tachyarrhythmia.S4.3.4-3,S4.3.4-4 In the setting of ventricular preexcitation, atrial tachyarrhythmia may expose the patient to a higher risk of lethal ventricular arrhythmia. In patients with clinical supraventricular tachycardia, management is according to existing GDMT.S4.3.4-19 A Pediatric & Congenital Electrophysiology Society (PACES)/HRS expert consensus document provides additional information on the manage- ment of arrhythmias.S4.3.4-20 4. Concealed accessory pathways are common in Ebstein anomaly and may coexist with manifest accessory pathways. In addition, preexcitation may be present but difficult to appreciate on the surface ECG. Tricuspid valve surgery can hinder transcatheter access to right-sided accessory pathways and the slow pathway in AV node reen- try, such that it may be reasonable to assess for arrhythmia substrates and proceed with catheter ablation if identified, before surgery. 5. Data demonstrate that delay of surgery until HF or RV systolic dysfunction ensues is associated with poorer outcomes; surgery before either of those develops is recommended.S4.3.4-6,S4.3.4-7,S4.3.4-10 Ebstein anomaly is understood as not just valve di- sease but also a myopathic process. Consequently, threshold for operation may be different than in other RV volume-loading lesions, because there is more concern regarding the capacity of the myo- pathic Ebstein right ventricle to tolerate a volume load. Also, there are cohort series of Ebstein patients to inform decisions.S4.3.4-6,S4.3.4-7,S4.3.4-10 Surgical repair generally consists of tricuspid valve repair (preferred when feasible) or replacement, selective plication of atrialized right ventricle, re- duction atrioplasty, arrhythmia surgery, and/or closure of atrial level shunt. 