Which patients with aortic stenosis should be considered for transcatheter therapies such as valvuloplasty or transcatheter aortic valve replacement (TAVR)?

Transcatheter Therapies for Aortic Stenosis: Patient Selection Guidelines

Transcatheter aortic valve replacement (TAVR) is strongly recommended for patients with severe, symptomatic, calcific stenosis of a trileaflet aortic valve who have prohibitive surgical risk (estimated ≥50% risk of mortality or irreversible morbidity at 30 days) and suitable aortic/vascular anatomy with predicted survival >12 months. 1, 2

Patient Selection Criteria

Recommended for TAVR:

1. Prohibitive Surgical Risk Patients:

   • Estimated ≥50% risk of mortality or irreversible morbidity at 30 days with surgery 1
   • Other factors including frailty, prior radiation therapy, porcelain aorta, severe hepatic or pulmonary disease 1, 2
   • Predicted survival >12 months 1

2. High Surgical Risk Patients:

   • STS-PROM score ≥8% 1
   • TAVR is a reasonable alternative to surgical AVR 1

3. Intermediate Surgical Risk Patients:

   • STS-PROM score between 3-8% 1
   • Heart Team determination of intermediate risk status

Anatomical Requirements:

• Suitable aortic annulus size for available TAVR devices 1
• Adequate vascular access (femoral, iliac, subclavian, axillary) or suitability for apical approach 1, 2
• Appropriate valve plane to coronary ostium height 1

Contraindications for TAVR:

• Bicuspid or non-calcified valves 1, 2
• Life expectancy <1 year 1, 2
• Severe disease of other valves requiring surgical intervention 2
• Active endocarditis 2
• Thrombus in left ventricle 2
• High risk of coronary ostium obstruction 2
• Inadequate vascular access for chosen approach 2

Balloon Aortic Valvuloplasty

Balloon aortic valvuloplasty (BAV) should be considered in limited circumstances:

• As palliation in adult patients with AS when surgical AVR cannot be performed due to serious comorbidities 1
• As a bridge to surgical AVR 1, 3

BAV alone has poor long-term outcomes due to early restenosis, with mortality rates of 50.7% at 1 year when used as standalone therapy compared to 30.7% with TAVR 4.

Heart Team Evaluation

A multidisciplinary Heart Team approach is mandatory for optimal patient selection 1:

• Cardiologists with expertise in valvular heart disease
• Structural interventional cardiologists
• Imaging specialists
• Cardiovascular surgeons
• Cardiovascular anesthesiologists
• Cardiovascular nursing professionals

Outcomes and Complications

TAVR Outcomes:

• Mortality: 3-5% (30-day) 1
• Stroke: 6-7% 1
• Access complications: 17% 1
• Pacemaker insertion: 2-9% (Sapien) or 19-43% (CoreValve) 1
• Paravalvular aortic regurgitation 1

Long-term data shows significant mortality benefit with TAVR vs. medical therapy:

• 5-year mortality: 71.8% with TAVR vs. 93.6% with standard treatment 5
• 1-year mortality: 30.7% with TAVR vs. 50.7% with standard therapy 4

Decision Algorithm for Aortic Stenosis Patients

1. Confirm severe symptomatic AS (Stage D):

   • High-gradient AS: Aortic velocity ≥4.0 m/s, mean gradient ≥40 mm Hg, AVA ≤1.0 cm² 1
   • Low-flow low-gradient AS with reduced LVEF: AVA ≤1.0 cm², velocity <4.0 m/s at rest but increases to ≥4.0 m/s with dobutamine 1
   • Low-flow low-gradient AS with normal LVEF: AVA ≤1.0 cm², velocity <4.0 m/s, mean gradient <40 mm Hg 1

2. Assess surgical risk:

   • STS-PROM score calculation
   • Frailty assessment
   • Major organ system dysfunction evaluation
   • Procedure-specific impediments

3. Risk-based recommendations:

   • Prohibitive risk: TAVR recommended 1, 2
   • High risk: TAVR is reasonable alternative to SAVR 1
   • Intermediate risk: Consider TAVR based on Heart Team assessment 1
   • Low risk: SAVR generally preferred 1

4. Evaluate anatomical suitability for TAVR:

   • Aortic annulus size and valve morphology
   • Vascular access options
   • Coronary height and risk of obstruction

Important Caveats

• TAVR is only indicated for calcific valvular AS; it has not been studied for congenital AS, rheumatic valve disease, or isolated aortic regurgitation 1
• Careful pre-procedural imaging is essential for device selection and procedural planning 2
• TAVR should only be performed in centers with cardiac surgery on-site 2
• The presence of extensive comorbidities may attenuate the survival benefit of TAVR 6
• Patients with predicted survival <12 months or <25% chance of survival with benefit at 2 years should be considered for palliative care rather than TAVR 1

By following these guidelines, clinicians can appropriately select patients who will benefit most from transcatheter therapies for aortic stenosis while minimizing procedural risks.