What are the criteria for surgery in a patient with Ebstein anomaly?

Surgical Criteria for Ebstein Anomaly

Surgical repair or reoperation for adults with Ebstein anomaly and significant tricuspid regurgitation is recommended when one or more of the following are present: heart failure symptoms, objective evidence of worsening exercise capacity, or progressive right ventricular systolic dysfunction by echocardiography or CMR. 1

Class I (Strongest) Indications for Surgery

Symptomatic patients with significant tricuspid regurgitation should undergo surgical intervention when:

• Heart failure symptoms are present (dyspnea, fatigue, exercise intolerance) 1
• Objective evidence of worsening exercise capacity is documented on formal exercise testing 1
• Progressive RV systolic dysfunction is demonstrated by echocardiography or CMR 1

These represent Class I, Level B-NR recommendations from the 2018 AHA/ACC guidelines, meaning surgery is definitively recommended based on the best available evidence. 1

Class IIa (Reasonable) Indications for Surgery

Surgery can be beneficial in patients with significant tricuspid regurgitation when:

• Progressive RV enlargement is documented on serial imaging 1
• Systemic desaturation from right-to-left atrial shunt is present (cyanosis, hypoxemia) 1
• Paradoxical embolism has occurred 1
• Atrial tachyarrhythmias are present and refractory to medical management 1

These represent Class IIa, Level B-NR recommendations, indicating that surgery is reasonable and can improve outcomes in these scenarios. 1

Specific Criteria Defining "Significant" Tricuspid Regurgitation

Severe TR is defined by echocardiographic criteria including:

• Central jet ≥50% of right atrium area 2
• Vena contracta width ≥7 mm 1, 2
• PISA radius >9 mm 2
• EROA ≥0.4 cm² 2
• Regurgitant volume ≥45 mL/beat 2
• Hepatic vein systolic flow reversal 2
• Dilated right heart chambers 2

Objective Markers of RV Dysfunction

Progressive RV dysfunction is indicated by:

• **TAPSE <17 mm** (normal >17 mm) 2
• **S' velocity <10 cm/s** (normal >10 cm/s) 2
• RV free wall longitudinal strain deterioration on speckle-tracking echocardiography 2
• Progressive RV dilation on serial CMR or echocardiography 1

Special Consideration: Bidirectional Cavopulmonary (Glenn) Anastomosis

A Glenn shunt at the time of Ebstein repair may be considered when:

• Severe RV dilation is present 1
• Severe RV systolic dysfunction is documented 1
• LV function is preserved 1
• Left atrial pressure and LV end-diastolic pressure are not elevated 1

This represents a Class IIb, Level B-NR recommendation for patients at high risk of RV failure after standard repair. 1, 3

Arrhythmia Management Before Surgery

Electrophysiological study and catheter ablation should be performed:

• Before tricuspid valve surgery even in the absence of preexcitation or documented supraventricular tachycardia (Class IIa) 1
• Definitively indicated for high-risk pathway conduction or multiple accessory pathways (Class I) 1

Approximately 25% of Ebstein patients have accessory pathways, with nearly 50% having multiple pathways. 4 Addressing these before valve surgery reduces perioperative arrhythmia risk. 1

Critical Contraindications to Surgery

Surgery should NOT be performed when:

• Severe irreversible RV dysfunction is present 2
• Irreversible pulmonary hypertension exists 2
• Irreversible liver dysfunction from chronic hepatic congestion is documented 2

These conditions predict futility of surgical intervention and are associated with prohibitive mortality. 2, 5

Age-Specific Considerations

Neonatal patients (highest mortality 23.4%): 6

• Surgery indicated for critically ill neonates with poor RV function using RV/RA exclusion combined with modified BT shunt 7
• Primary biventricular repair reserved for those with good RV function 7

Older children and adults (mortality 0.7-1.1%): 6

• Standard criteria apply as outlined above 1
• Tricuspid valve repair preferred over replacement when feasible 2, 5

Common Pitfalls to Avoid

Do not delay surgery in symptomatic patients with preserved RV function, as progressive RV dysfunction worsens surgical outcomes and may render patients inoperable. 2, 5

Do not ignore objective exercise testing in subjectively "asymptomatic" patients—exercise capacity is often abnormal and provides critical prognostic information. 1

Do not overlook accessory pathways—preoperative electrophysiological evaluation prevents perioperative arrhythmic complications. 1, 4

Do not use increased hematocrit/hemoglobin as a reason to defer surgery—elevated values indicate chronic hypoxemia and are actually associated with worse outcomes, making earlier intervention more appropriate. 5