What type of surgery is recommended for a patient with Tetralogy of Fallot (TOF)?

Surgical Management of Tetralogy of Fallot

Primary Surgical Approach

Complete surgical repair should be performed in infancy, typically between 3-6 months of age, consisting of VSD closure and relief of right ventricular outflow tract (RVOT) obstruction, achieving hospital mortality of 0-2.1% and 30-year survival exceeding 90%. 1, 2

The definitive repair addresses all four anatomic components simultaneously: 1, 2

• VSD closure using a patch technique
• Relief of RVOT obstruction through infundibulotomy and resection of obstructive muscle bundles
• Pulmonary valve management (preservation when feasible vs. transannular patch)
• Extracardiac conduit placement when necessary

Surgical Technique Selection

Two main approaches exist for RVOT reconstruction, with critical implications for long-term outcomes: 1

Valve-Sparing Approach (Preferred When Anatomically Feasible)

• Combined transatrial-transpulmonary approach should be employed when pulmonary valve anatomy permits preservation 3
• This technique minimizes long-term RV volume overload and reduces need for reintervention 1, 4
• Freedom from RVOT reintervention is significantly higher (100% at 8 years vs. 40% with transannular patch) 4

Transannular Patch Repair

• Required when valve preservation is not feasible (approximately 66% of cases) 3
• This approach inevitably causes severe pulmonary regurgitation and subsequent RV volume overload 1
• Should be avoided when anatomically possible to minimize long-term complications 1

Preoperative Imaging Requirements

Prior to any surgical intervention: 1, 2

• Cardiac MRI is essential to evaluate detailed anatomy, ventricular function, valve function, hemodynamics, and tissue characterization with late gadolinium enhancement for prognostication
• Coronary angiography is mandatory when anomalous coronary artery is suspected to delineate the course before RVOT interventions and avoid coronary compression during repair 2

Expected Surgical Outcomes

Contemporary results demonstrate: 1, 2, 3

• Hospital mortality: 0-2.1%
• 30-year survival: >90%
• Mean postoperative RVOT gradient: 15 mm Hg
• Mean post-repair peak RV/systemic pressure ratio: 0.48

Reintervention Surgery (Pulmonary Valve Replacement)

Indications for Reoperation

Pulmonary valve replacement (surgical or percutaneous) is recommended for: 5

Class I (Symptomatic Patients):

• Moderate or greater pulmonary regurgitation with cardiovascular symptoms not otherwise explained (dyspnea, chest pain, exercise intolerance)

Class IIa (Asymptomatic Patients):

• Moderate or greater pulmonary regurgitation PLUS any of the following: 5
  • Progressive or severe RV enlargement (RVEDVI ≥160 mL/m² or RVESVI ≥80 mL/m²)
  • RV or LV systolic dysfunction
  • RVEDV ≥2× LVEDV
  • Progressive reduction in objective exercise tolerance
  • Sustained tachyarrhythmias

Class IIb:

• Moderate or greater pulmonary regurgitation with other lesions requiring surgical interventions 5
• Moderate or greater pulmonary regurgitation with ventricular tachyarrhythmia (in addition to arrhythmia management) 5

Surgical Options for Reintervention

Heterograft (porcine or pericardial) or homograft is preferred for pulmonary valve replacement 5, 6

Additional procedures that may be required during reintervention: 5

• Resection of subvalvular obstruction and/or patch augmentation of RVOT, pulmonary annulus, main or branch pulmonary arteries
• Residual/recurrent VSD closure (direct suture or patch revision)
• Tricuspid valve repair for significant regurgitation
• Aneurysm or pseudoaneurysm resection of RVOT with patch replacement
• Arrhythmia surgery (modified right atrial maze procedure or ablation)
• Closure of residual PFO or ASD, especially with cyanosis or history of paradoxical embolism

Mechanical PVR should only be used in patients who require warfarin anticoagulation for other reasons, as this has been associated with late malfunction from pannus formation 5

Lifelong Surveillance Requirements

All patients require annual follow-up with an adult congenital heart disease (ACHD) specialist including: 1, 2, 6

• History and physical examination
• 12-lead ECG
• Comprehensive echocardiography
• Cardiac MRI for precise RV volume quantification and pulmonary regurgitation assessment (essential because severity is often underestimated by clinical examination) 1
• Periodic Holter monitoring (frequency individualized based on hemodynamics and clinical suspicion) 6

Critical Pitfalls to Avoid

The transannular patch approach inevitably causes severe pulmonary regurgitation - valve-sparing techniques should be employed when anatomically feasible to minimize long-term RV volume overload and reduce reintervention rates 1, 4

Delayed recognition of RV dysfunction is common because the severity of pulmonary regurgitation is often underestimated by clinical examination alone, requiring serial CMR imaging for accurate assessment 1

Coronary artery compression testing is mandatory before right ventricle-to-PA conduit stenting or transcatheter valve placement to avoid catastrophic complications 5