What is the treatment for tricuspid valve atresia?

Treatment of Tricuspid Valve Atresia

Tricuspid atresia requires staged surgical palliation culminating in the Fontan procedure, which directs systemic venous return directly to the pulmonary arteries, bypassing the absent right atrioventricular connection. 1, 2

Understanding the Defect

Tricuspid atresia is a congenital heart defect where the tricuspid valve is completely absent, eliminating direct communication between the right atrium and right ventricle. 1 This creates obligatory right-to-left shunting at the atrial level and requires an alternative pathway for pulmonary blood flow. 3 The condition represents approximately 1% of all congenital heart disease cases. 2

Surgical Management Strategy

Initial Palliation in Infancy

The first surgical intervention typically involves creating an aortopulmonary shunt to ensure adequate pulmonary blood flow. 2 This palliative procedure stabilizes the patient and allows growth before definitive repair. 4

• Glenn anastomosis (superior vena cava to right pulmonary artery connection) may be performed as an intermediate stage, reducing volume load on the single functional ventricle. 5
• The timing and type of initial palliation depend on the adequacy of pulmonary blood flow and the presence of associated defects. 3

Definitive Repair: The Fontan Procedure

The Fontan operation is the definitive treatment, connecting systemic venous return directly to the pulmonary arterial circulation. 2, 4 This procedure effectively "ventriculizes" the right atrium to direct blood flow to the lungs without passing through a right ventricle. 4

Prerequisites for Fontan Surgery:

• Adequate pulmonary artery size and low pulmonary vascular resistance are essential for successful outcomes. 4
• Sufficient patient development and growth must be achieved before attempting definitive repair. 4
• Normal left ventricular function is critical since the left ventricle must support the entire cardiac output. 2

Surgical Technique:

The modern Fontan involves creating a pathway where:

• Inferior vena caval blood is directed to the left lung 4
• Superior vena caval blood reaches the right pulmonary artery through cava-pulmonary anastomosis 4
• Only oxygenated blood returns to the left heart 4

Patient Selection and Timing

Children who are too young or have inadequately sized pulmonary arteries should receive palliative procedures first, with definitive repair delayed until optimal conditions exist. 4

Key anatomic considerations include:

• Ventricular and great vessel relationships must be defined by left ventriculography, particularly using biplane imaging with long axial views. 3
• Associated congenital defects (ventricular septal defects, pulmonary stenosis, transposition) influence surgical approach. 3, 6

Long-Term Outcomes

Long-term results of the Fontan procedure have been very good, with successful palliation allowing survival into adulthood. 2 However, patients face lifelong complications requiring ongoing management. 1

• Some patients with naturally balanced pulmonary and systemic circulations have survived to ages 21-41 years without surgery, though this is exceptional. 3
• Prudent surgical decisions based on accurate anatomic diagnosis and optimal pulmonary blood flow are critical for favorable prognosis. 3

Critical Pitfalls to Avoid

• Do not attempt Fontan procedure in patients with elevated pulmonary vascular resistance or inadequate pulmonary artery size—this leads to poor outcomes and right atrial hypertension. 4
• Do not delay initial palliation in severely cyanotic infants—early shunt procedures prevent complications from chronic hypoxemia. 2
• Ensure comprehensive anatomic assessment before any surgical intervention—unrecognized associated defects can compromise surgical success. 3

Lifelong Follow-Up Requirements

All patients require specialized lifelong cardiac care in grown-up congenital heart disease (GUCH) centers, even after successful Fontan completion. 1 Complications include arrhythmias, ventricular dysfunction, protein-losing enteropathy, and thromboembolic events requiring ongoing surveillance and management. 1