What is the management and treatment for a bicuspid (two-cusped) tricuspid valve?

Management and Treatment of Bicuspid Tricuspid Valve

Tricuspid valve replacement is the recommended treatment for bicuspid tricuspid valve, as this congenital abnormality typically causes severe tricuspid regurgitation that is not amenable to repair techniques.

Understanding Bicuspid Tricuspid Valve

A bicuspid tricuspid valve is a rare congenital heart defect where the tricuspid valve has only two cusps instead of the normal three. This anatomical abnormality:

• Is distinct from the more common bicuspid aortic valve
• Results in abnormal valve function, typically causing significant tricuspid regurgitation (TR)
• May be associated with other congenital heart defects

Diagnostic Evaluation

Imaging

• Echocardiography: Essential for assessing valve structure, measuring annular size, and quantifying TR severity 1
• Cardiac MRI: Useful for precise quantification of right ventricular volumes, function, and tricuspid valve anatomy 2
• 3D Echocardiography: May be necessary for accurate planimetry of the valve area 1

Hemodynamic Assessment

• Measure right ventricular systolic pressure and tricuspid valve gradient
• Assess right ventricular function and size
• Evaluate for associated lesions (e.g., atrial septal defects)

Treatment Algorithm

1. Surgical Management

• Tricuspid valve replacement is preferred when valve leaflets are significantly deformed or abnormal 1

  • Bioprosthetic valve is strongly preferred over mechanical valve due to high risk of thromboembolism with mechanical valves in tricuspid position 1
  • Consider insertion of permanent epicardial pacing electrode during surgery to avoid later need for transvenous lead across prosthetic valve 1

• Tricuspid valve repair may be considered only if:

  • There is a mobile anterior leaflet free of tethering 1
  • The functional right ventricle is more than one-third of the total right ventricle 1
  • However, repair is rarely feasible with congenital bicuspid valves due to significant structural abnormalities

2. Percutaneous Options

• Percutaneous tricuspid valve replacement may be considered in high-risk surgical candidates who have:
  • Prior tricuspid valve surgery 3
  • Significant stenosis and/or regurgitation of a bioprosthetic tricuspid valve 3
  • This approach has shown procedural success with reduction in mean gradient and TR 3

3. Medical Management

• Loop diuretics to reduce volume overload 2
• Aldosterone antagonists for patients with systemic congestion 2
• Regular monitoring of:
  • TR severity via echocardiography
  • Right ventricular function
  • Symptoms of right heart failure 2

Indications for Intervention

Class I (Strong) Recommendations:

• Symptomatic patients with severe primary TR without severe RV dysfunction 1, 2
• Severe TR in patients undergoing left-sided valve surgery 1, 2

Class IIa (Reasonable) Recommendations:

• Asymptomatic or mildly symptomatic patients with severe isolated primary TR and progressive RV dilatation or deterioration of RV function 2

Special Considerations

Timing of Surgery

• Early intervention is critical as delaying surgery until severe RV dysfunction develops significantly worsens outcomes 2
• Progressive right heart dilation or reduction of RV systolic function should prompt consideration for surgery 1

Contraindications for Surgery

• Severe RV dysfunction with very large annuli and significant leaflet tethering 2
• Irreversible liver cirrhosis 2

Follow-up

• Regular echocardiographic surveillance is essential post-intervention 2
• Monitor for:
  • Prosthetic valve function
  • Right ventricular function
  • Development of arrhythmias

Pitfalls and Caveats

1. Misdiagnosis: Bicuspid tricuspid valve may be mistaken for other forms of tricuspid valve disease; accurate imaging is essential for proper diagnosis

2. Delayed intervention: Waiting until severe RV dysfunction develops leads to significantly worse outcomes; early intervention is key

3. Inappropriate repair attempts: Unlike some acquired tricuspid valve diseases, congenital bicuspid valves rarely respond well to repair techniques due to fundamental structural abnormalities

4. Inadequate follow-up: Lifelong monitoring is required after diagnosis or intervention to detect deterioration in valve or ventricular function