What is the recommended treatment for patients with severe aortic stenosis, normal ejection fraction (EF), and high velocity and mean gradient?

Treatment for Severe Aortic Stenosis with Normal Ejection Fraction and High Velocity/Gradient

For patients with severe aortic stenosis, normal ejection fraction, and high velocity/gradient, aortic valve replacement (AVR) is strongly recommended as it significantly improves mortality and quality of life. 1

Diagnostic Criteria for Severe Aortic Stenosis

• Severe aortic stenosis is defined as:
  • Peak aortic valve velocity (Vmax) ≥4.0 m/sec
  • Mean gradient ≥40 mmHg
  • Aortic valve area (AVA) ≤1.0 cm² (or indexed AVA ≤0.6 cm²/m²)

Treatment Algorithm Based on Symptoms and Risk

Symptomatic Patients

• Symptomatic patients with severe, high-gradient aortic stenosis require immediate intervention 1
• Without intervention, symptomatic patients have a poor prognosis with average survival of only 2-3 years 2
• The choice between TAVR and SAVR should be based on:
  • Surgical risk assessment
  • Patient age
  • Anatomical considerations
  • Comorbidities

Asymptomatic Patients

For asymptomatic patients with severe AS, high gradient, and normal EF:

1. Very severe AS (Vmax ≥5 m/sec or mean gradient ≥60 mmHg):

   • AVR is appropriate (rating 7-8/9) regardless of surgical risk 1
   • No intervention is rarely appropriate (rating 2/9) for low surgical risk patients

2. Severe AS (Vmax 4.0-4.9 m/sec) with abnormal exercise stress test:

   • AVR is appropriate (rating 8/9) regardless of surgical risk 1
   • No intervention is rarely appropriate (rating 2-3/9)

3. Severe AS with predictors of rapid progression (e.g., ΔVmax >0.3 m/s/year, severe valve calcification, elevated BNP, excessive LV hypertrophy):

   • AVR is appropriate (rating 7-8/9) regardless of surgical risk 1
   • No intervention may be appropriate (rating 4/9)

4. Severe AS with no predictors of progression and negative stress test:

   • No intervention is appropriate (rating 7/9)
   • AVR may be appropriate (rating 5/9)

Special Considerations

Reduced LVEF (<50%)

• AVR is strongly recommended (rating 8-9/9) for patients with severe AS and LVEF <50% 1
• No intervention is rarely appropriate (rating 1-2/9)
• Recent evidence suggests that even LVEF <55% (but still ≥50%) may be a marker of poor outcome, suggesting earlier intervention may be beneficial 3

Low-Flow, Low-Gradient AS with Preserved EF

• For patients with AVA ≤1.0 cm² but mean gradient <40 mmHg despite normal EF:
  • Confirm measurements and rule out errors
  • Assess stroke volume index (SVI)
  • If SVI <35 mL/m², evaluate for true severe AS versus pseudosevere AS 4
  • Evidence suggests AVR improves survival in these patients regardless of gradient 5

Choice of Intervention

The Heart Team should determine the optimal intervention strategy:

1. Low surgical risk patients (STS or EuroSCORE II <4%):

   • SAVR is recommended 1

2. Intermediate to high surgical risk patients:

   • Either TAVR or SAVR may be appropriate
   • Decision should be individualized based on anatomical factors and comorbidities 1

3. Patients unsuitable for SAVR:

   • TAVR is recommended 1

Pitfalls to Avoid

1. Misclassifying symptomatic patients as "asymptomatic":

   • Patients may reduce activity to avoid symptoms
   • Exercise testing can unmask symptoms and risk

2. Delaying intervention in appropriate candidates:

   • Once symptoms develop, mortality increases dramatically without AVR
   • Even in asymptomatic patients, certain high-risk features warrant early intervention

3. Overlooking reduced LVEF:

   • Even mild reductions in LVEF (50-55%) may indicate need for earlier intervention 3

4. Ignoring flow status in patients with discordant measurements:

   • Low-flow states can mask severe AS by reducing the gradient despite severe stenosis

By following these evidence-based recommendations, clinicians can optimize outcomes for patients with severe aortic stenosis, normal ejection fraction, and high velocity/gradient.