What is the management of double outlet right ventricle (DORV)?

Management of Double Outlet Right Ventricle (DORV)

Management of DORV must be individualized based on the specific anatomic variant, as this heterogeneous condition encompasses lesions ranging from tetralogy of Fallot-like physiology to transposition-type anatomy, with surgical approaches including VSD closure with intraventricular tunneling, right ventricle-to-pulmonary artery conduit placement, Rastelli-type repair, or single-ventricle palliation depending on the underlying anatomy. 1

Anatomic Classification and Surgical Strategy

The surgical approach to DORV is fundamentally determined by the relationship between the ventricular septal defect (VSD) and the great arteries 1:

Subaortic or Doubly Committed VSD (TOF-like)

• When the aorta is closely related to the VSD, management follows principles similar to tetralogy of Fallot repair 1
• Surgical repair involves intraventricular tunnel creation from the VSD to the aorta 2
• If right ventricular outflow tract obstruction exists, augmentation of the RVOT or conduit placement from RV to pulmonary artery is necessary 1, 2
• Critical caveat: DORV patients have higher risk of residual left ventricular outflow tract obstruction compared to standard TOF 1

Subpulmonary VSD (Taussig-Bing Anomaly)

• When the pulmonary artery is more closely related to the VSD than the aorta, management resembles d-transposition of the great arteries with VSD 1
• Arterial switch operation is indicated with tunneling of the VSD to the neoaorta 2
• These patients have demonstrated excellent early results, though long-term surveillance for neoaortic valve regurgitation is required 2

Complex Anatomy Requiring Single-Ventricle Palliation

• Remote VSD location, complex atrioventricular valve abnormalities, or unbalanced ventricles necessitate staged single-ventricle palliation 1, 2
• Staged approach culminates in Fontan physiology 2

Long-Term Surveillance and Follow-Up

Routine Monitoring Schedule (Physiological Stage C and D)

For Stage C patients 1:

• ACHD cardiologist visits every 6-12 months
• ECG every 12 months
• Transthoracic echocardiography every 12 months
• Pulse oximetry at each visit
• CMR imaging as needed for assessment of RV function and anatomy
• Exercise testing (6-minute walk or CPET) every 6-12 months
• Cardiac catheterization as clinically indicated

For Stage D patients 1:

• ACHD cardiologist visits every 3-6 months
• ECG every 12 months
• Transthoracic echocardiography every 12 months
• Pulse oximetry at each visit
• CMR imaging as needed
• Exercise testing every 6-12 months
• Cardiac catheterization as clinically indicated

Critical Surveillance Targets

Pulmonary hypertension screening 1:

• Adults with septal or great artery shunts require periodic screening for pulmonary hypertension with TTE (Class I, Level B-NR)
• Cardiac catheterization to assess pulmonary vascular hemodynamics is recommended for patients with clinical symptoms, signs, or echocardiographic findings suggestive of pulmonary hypertension (Class I, Level B-NR)
• Patients with pulmonary vascular resistance ≥2.5 Wood units (>4 Wood units×m²) should be assessed collaboratively by an ACHD cardiologist and pulmonary hypertension expert (Class I, Level B-NR)

Conduit surveillance 2:

• Patients requiring RV-to-PA conduit placement will need subsequent surgery for conduit replacement
• Serial imaging to assess conduit function and stenosis is essential

Subaortic obstruction monitoring 2:

• Complex intraventricular tunnels carry risk for developing subaortic obstruction
• Regular assessment of LVOT gradients is mandatory

Common Pitfalls and Management Challenges

Residual LVOT Obstruction

• DORV patients are at significantly higher risk for residual LVOT obstruction compared to standard conotruncal repairs 1
• Requires vigilant echocardiographic surveillance with specific attention to subaortic gradients
• May necessitate reoperation if hemodynamically significant

Reoperation Risk

• Complex biventricular intracardiac repairs have been associated with higher risk of reoperation 2
• Conduit-dependent repairs universally require eventual conduit replacement 2
• Neoaortic valve regurgitation after arterial switch operations may require subsequent intervention 2

Single-Ventricle Complications

• For patients with Fontan physiology, long-term complications include arrhythmias and protein-losing enteropathy 2
• Despite improved early and late survival in recent decades, these patients require specialized ACHD center follow-up 2

Cardiac Catheterization Indications

Hemodynamic assessment is beneficial 1:

• Before or at time of shunt closure to assess suitability for closure (Class I, Level B-NR)
• When clinical symptoms, signs, or echocardiographic findings suggest pulmonary hypertension (Class I, Level B-NR)
• BNP, chest x-ray, 6-minute walk test, and cardiac catheterization are useful for initial and follow-up evaluation of ACHD patients with pulmonary arterial hypertension (Class I, Level C-EO)

Specialized Care Requirements

• All DORV patients should be managed in specialized ACHD centers with access to congenital cardiac surgeons, ACHD cardiologists, cardiac anesthesiologists with CHD expertise, and advanced imaging capabilities including CMR and CCT 1
• Multidisciplinary team approach is essential given the anatomic heterogeneity and complexity of surgical repairs 3, 2