Ebstein anomaly can occur with other defects including ASD, VSD, and PS. A patent foramen ovale, otherwise usually considered normal, may have signif- icant impact in Ebstein anomaly. Accessory pathways and arrhythmias are relatively common. Patient sur- veillance and management varies depending on age, severity of the lesion, and associated abnormalities including HF, cyanosis, and arrhythmias. Surveillance includes echocardiographic and other advanced imag- ing to assess RV size and function, rhythm assessment, pulse oximetry, and stress testing. Treatments include medical and surgical therapy for patients with manifest symptoms as well as catheter-based structural and elec- trophysiological interventions when indicated. Table 25. Double-Chambered Right Ventricle: Routine Follow-Up and Testing Intervals Frequency of Routine Follow-Up and Testing Physiological Stage A* (mo) Physiological Stage B* (mo) Physiological Stage C* (mo) Physiological Stage D* (mo) *See Tables 3 and 4 for details on the ACHD AP classification system. 6-minute walk test or CPET, depending on clinical indication. ACHD indicates adult congenital heart disease; CPET, cardiopulmonary exercise test; ECG, electrocardiogram; and TTE, transthoracic echocardiogram. Recommendations for Ebstein Anomaly (Continued) COR LOE Recommendations CLINICAL STATEMENTS AND GUIDELINES See Section 3.3 for recommendations on who should perform surgeries, cardiac catheterization, and other procedures in these patients; Section 3.4 for rec- ommendations on diagnostic evaluation; and Table 26 for routine testing and follow-up intervals. Recommendation-Specific Supportive Text 1. Deciphering the anatomy and size of the right atrium and right ventricle in Ebstein anomaly is often difficult using echocardiography alone, par- ticularly in adults. Data obtained from CMR can inform clinical care and surgical planning or de- cision-making, because CMR data correlate well with intraoperative findings. 2. 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. 