What are the indications for transcatheter tricuspid valve (TTV) intervention?

Indications for Transcatheter Tricuspid Valve Intervention

Transcatheter tricuspid valve (TTV) interventions are primarily indicated for patients with severe tricuspid regurgitation who are symptomatic despite optimal medical therapy and are at high surgical risk or inoperable. 1

Primary Indications

Severe Tricuspid Regurgitation

• Symptomatic patients with severe TR who are high-risk for surgery
  • Patients with NYHA functional class III-IV symptoms
  • Patients with right-sided heart failure despite optimal medical therapy
  • Patients with progressive right ventricular dilatation or dysfunction 1

High Surgical Risk Factors

• Advanced age (>70 years)
• Multiple comorbidities
• Previous cardiac surgeries
• Severe right ventricular dysfunction
• Liver dysfunction (elevated bilirubin)
• Renal dysfunction (GFR <30 mL/min)
• Significant pulmonary hypertension 1

Patient Selection Criteria

Anatomical Considerations

• Tricuspid regurgitation severity:
  • Quantitative assessment showing regurgitant volume ≥45 mL or regurgitant fraction ≥50% (high-risk category) 1
  • Severe TR with significant annular dilatation (≥40 mm) 1

Functional Status

• Persistent symptoms despite guideline-directed medical therapy
• Evidence of right ventricular dysfunction or progressive dilatation
• Elevated right atrial pressure (>15 mmHg) 1, 2

Risk Stratification

• TRI-SCORE can be used to assess surgical risk:
  • Low risk: <3 points
  • Intermediate risk: 4-5 points
  • High risk: ≥6 points
• Points assigned for: age >70 (+1), NYHA III-IV (+1), right-sided HF (+2), furosemide >125mg daily (+2), GFR <30 (+2), elevated bilirubin (+2), LVEF <60% (+1), moderate/severe RV dysfunction (+1) 1

Types of Transcatheter Tricuspid Interventions

1. Edge-to-edge leaflet repair - For patients with suitable leaflet anatomy and moderate coaptation defects 3

2. Annuloplasty devices - For patients with annular dilatation without severe leaflet tethering 3

3. Caval valve implantation - For patients with severe TR and right heart failure, especially with atrial functional TR 4

4. Spacer devices - For patients with large coaptation gaps 3

5. Total valve replacement - For patients with severe anatomical deformities of the valve or when repair techniques are unlikely to be successful 5

Contraindications

• Irreversible severe right ventricular dysfunction
• Irreversible liver cirrhosis
• Severe pulmonary hypertension
• Anatomical features unsuitable for specific device implantation 1

Imaging Assessment

• Multimodality imaging is essential for patient selection:
  • Echocardiography (transthoracic and transesophageal)
  • Cardiac MRI for quantitative assessment of regurgitant volume
  • CT for detailed anatomical assessment 1, 3

Clinical Outcomes

Early clinical data show that TTV interventions can:

• Reduce TR severity by 1-2 grades
• Improve NYHA functional class
• Improve quality of life
• Potentially reduce mortality compared to medical management alone 2

Current Status

It's important to note that while TTV interventions show promise, they are still evolving with multiple ongoing clinical trials including TRILUMINATE, TRI-FR, CLASP II TR, and TRISCEND II 1. Many procedures are currently performed on compassionate grounds or within clinical trials, with the field rapidly evolving as new evidence emerges 6, 2.

The optimal timing of intervention remains debated, but there is growing evidence that earlier intervention before irreversible right ventricular dysfunction occurs may lead to better outcomes 4.