What is the optimal management for a patient with Tricuspid Valve Atresia, hypoplastic right ventricle, Left Ventricular (LV) hypertrophy, right atrial enlargement, good left ventricular systolic function, patent Ductus Arteriosus (PDA), and severe pulmonic stenosis?

Management of Tricuspid Valve Atresia with Complex Cardiac Anatomy

This patient requires urgent referral to a specialized congenital cardiac surgery center for staged single-ventricle palliation, with immediate prostaglandin E1 infusion to maintain ductal patency and prevent circulatory collapse.

Immediate Medical Management

Prostaglandin E1 (PGE1) infusion must be initiated immediately to maintain patency of the 0.2cm PDA, which is the sole source of pulmonary blood flow given the severe pulmonic stenosis with minimal forward flow 1. The small pulmonary arteries (0.3cm) and hypoplastic right ventricle make this patient entirely dependent on ductal flow for oxygenation.

• Start PGE1 at 0.01-0.05 mcg/kg/min and titrate to maintain adequate oxygen saturation (typically 75-85% in ductal-dependent lesions) 1
• Monitor for PGE1 side effects including apnea, hypotension, and fever
• Avoid supplemental oxygen, which can cause ductal constriction and precipitate cardiovascular collapse

Surgical Strategy: Single-Ventricle Pathway

This anatomy—tricuspid atresia, hypoplastic right ventricle, and severe pulmonic stenosis—mandates single-ventricle palliation following the Fontan pathway 2, 1.

Stage 1: Neonatal/Initial Palliation

The first intervention should be either PDA stenting or a modified Blalock-Taussig shunt to establish reliable pulmonary blood flow 1.

• PDA stenting is preferred when the ductus anatomy is favorable (straight course, adequate length), as it avoids thoracotomy and preserves pulmonary artery architecture 1
• Balloon atrial septostomy should be performed if there is any restriction at the atrial level to ensure adequate left atrial decompression 1
• Modified Blalock-Taussig shunt (3-3.5mm) is the alternative if PDA stenting is not feasible anatomically 1

Stage 2: Bidirectional Glenn Shunt (4-6 months)

Superior cavopulmonary anastomosis (bidirectional Glenn) should be performed at 4-6 months of age to reduce volume load on the single functional left ventricle 2, 1.

• This connects the superior vena cava directly to the pulmonary arteries, providing passive pulmonary blood flow from the upper body 2
• Timing depends on adequate pulmonary artery growth and low pulmonary vascular resistance
• The small initial pulmonary artery size (0.3cm) will require careful monitoring for adequate growth before proceeding 1

Stage 3: Fontan Completion (2-4 years)

Total cavopulmonary connection (Fontan procedure) should be completed when the child reaches 2-4 years of age, provided pulmonary vascular resistance remains low and ventricular function is preserved 1.

• This directs inferior vena cava blood to the pulmonary arteries via an extracardiac conduit or lateral tunnel
• Prerequisites include mean pulmonary artery pressure <15 mmHg, pulmonary vascular resistance <3 Wood units, and preserved left ventricular function (EF >55%) 1
• The current EF of 66% is favorable for eventual Fontan completion

Critical Anatomic Considerations

The severely hypoplastic pulmonary arteries (0.3cm) and annulus (0.3cm) represent the most significant risk factor for poor outcomes in this staged approach 1.

• Pulmonary artery growth must be monitored closely with serial echocardiography after Stage 1 palliation
• If pulmonary arteries fail to grow adequately, additional interventions such as pulmonary artery angioplasty or stenting may be required before Glenn or Fontan procedures 1
• The presence of LV hypertrophy with good systolic function (EF 66%) is favorable, as the left ventricle will serve as the systemic ventricle throughout life

Monitoring and Follow-up

• Serial echocardiography every 1-3 months to assess pulmonary artery growth, ventricular function, and AV valve competence 3
• Cardiac catheterization before each surgical stage to measure pulmonary artery pressures and resistance 1
• Monitor for development of aortopulmonary collaterals, which can cause volume overload and may require coil embolization

Common Pitfalls to Avoid

Do not attempt biventricular repair in this patient—the combination of tricuspid atresia and hypoplastic right ventricle makes this anatomically impossible 1, 4.

• Avoid excessive supplemental oxygen in the neonatal period, which increases pulmonary blood flow and can cause pulmonary overcirculation and heart failure
• Do not delay Stage 1 palliation—without intervention, ductal closure will be fatal 1
• The right atrial enlargement will persist and is expected in tricuspid atresia; it does not require specific intervention 4