What is the treatment for double outlet right ventricle?

Treatment of Double Outlet Right Ventricle

The treatment of double outlet right ventricle (DORV) is fundamentally determined by the anatomic relationship between the ventricular septal defect (VSD) and the great arteries, with surgical options ranging from biventricular repair with intraventricular tunneling to single-ventricle palliation, and all patients must be managed in specialized adult congenital heart disease (ACHD) centers. 1

Surgical Strategy Based on VSD Position

The surgical approach is dictated by VSD location and its relationship to the great vessels 1, 2:

Subaortic or Doubly Committed VSD (Without RVOT Obstruction)

• Perform intraventricular tunnel repair from the VSD to the aorta 1, 2, 3
• This approach has demonstrated 83% actuarial survival at 15 years with current hospital mortality of 5% 3
• When the aorta is closely related to the VSD, management principles mirror tetralogy of Fallot repair 1

Subaortic VSD With Right Ventricular Outflow Tract Obstruction

• Augment the RVOT or place a right ventricle-to-pulmonary artery conduit 1, 2
• Recognize that conduit placement necessitates subsequent surgeries for conduit replacement 2
• DORV patients carry higher risk of residual left ventricular outflow tract obstruction compared to standard tetralogy of Fallot, requiring vigilant surveillance 1

Subpulmonary VSD (Taussig-Bing Anomaly)

• Perform arterial switch operation with VSD tunneling to the neoaorta 2, 3
• Arterial switch has shown excellent results to date 2
• Monitor for potential neoaortic valve regurgitation requiring reoperation 2
• Consider intraventricular tunnel repair when the distance from tricuspid to pulmonary valve exceeds the distance from tricuspid to aortic valve; otherwise, spiral intraventricular tunnel or arterial switch is preferred 3

Remote VSD, Complex AV Valve Abnormalities, or Unbalanced Ventricles

• Pursue staged single-ventricle palliation culminating in Fontan physiology 1, 2
• This pathway includes initial systemic-to-pulmonary artery shunt or ventricular-to-pulmonary artery (Sano) shunt, followed by bidirectional superior cavopulmonary connection at 3-6 months, and completion Fontan at 2-5 years 4
• Long-term complications include arrhythmias and protein-losing enteropathy 2

Specialized Care Requirements

All DORV patients require management in specialized ACHD centers with the following capabilities 1:

• Access to congenital cardiac surgeons
• ACHD cardiologists
• Cardiac anesthesiologists with congenital heart disease expertise
• Advanced imaging including cardiac magnetic resonance (CMR) and cardiac computed tomography (CCT)

Diagnostic Imaging Strategy

Pre-operative Assessment

• Echocardiography is typically sufficient for anatomic and hemodynamic characterization in the native state 4
• CMR is indicated when echocardiography inadequately delineates pulmonary artery or pulmonary venous anatomy, or when determining feasibility of 1- versus 2-ventricle repair in borderline cases 4
• Cardiac CT may be considered as an alternative when only anatomic information is needed (without ventricular function or flow data), though radiation risk must be weighed 4

Intraoperative Monitoring

• Transesophageal echocardiography (TOE) is not routinely required unless coexisting atrioventricular valve pathology necessitates complete morphology and function evaluation before and after repair 4
• TOE may offer superior visualization of left ventricular outflow tract obstruction morphology, particularly with 3D imaging 4

Long-Term Surveillance Protocol

Stage C Patients (Moderate Complexity)

The following surveillance schedule is recommended 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 clinically indicated
• Exercise testing every 6-12 months
• Cardiac catheterization as clinically indicated

Stage D Patients (High Complexity)

More intensive monitoring is required 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

Pulmonary Hypertension Screening

Periodic screening for pulmonary hypertension with transthoracic echocardiography is mandatory for all adults with septal or great artery shunts 1

Indications for Cardiac Catheterization

• Perform cardiac catheterization when clinical symptoms, signs, or echocardiographic findings suggest pulmonary hypertension 1
• Hemodynamic assessment before or at the time of shunt closure to determine suitability for closure 1
• 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 1

Management of Elevated Pulmonary Vascular Resistance

• Patients with pulmonary vascular resistance ≥2.5 Wood units (>4 Wood units×m²) require collaborative assessment by an ACHD cardiologist and pulmonary hypertension expert 1

Critical Pitfalls to Avoid

• Complex biventricular intracardiac repairs carry higher reoperation risk 2
• Complex intraventricular tunnels are at risk for developing subaortic obstruction requiring ongoing surveillance 2
• Failure to recognize the need for specialized ACHD center management can compromise outcomes 1
• Inadequate long-term follow-up may miss development of pulmonary hypertension, arrhythmias, or conduit dysfunction 1, 2