What are the management options for patients with severe symptomatic aortic stenosis?

Management of Severe Symptomatic Aortic Stenosis

Aortic valve replacement is the definitive treatment for patients with severe symptomatic aortic stenosis, as it significantly reduces mortality and improves quality of life. 1

Diagnosis and Confirmation of Severe Symptomatic Aortic Stenosis

Severe aortic stenosis is defined by:

• Aortic valve area <1.0 cm²
• Mean gradient ≥40 mmHg
• Maximum velocity ≥4.0 m/s

Symptoms that indicate intervention is needed:

• Exertional dyspnea
• Heart failure
• Angina
• Syncope or presyncope

Management Options

1. Surgical Aortic Valve Replacement (SAVR)

SAVR is indicated for:

• Symptomatic patients with severe aortic stenosis at low to moderate surgical risk 1
• Younger patients (<65 years) 1
• Patients with anatomy unfavorable for TAVI (excessive calcification, annulus size out of range) 1
• Patients requiring concomitant cardiac surgery (CABG, other valve surgery, aortic surgery) 1

2. Transcatheter Aortic Valve Implantation (TAVI)

TAVI is indicated for:

• Symptomatic patients with severe aortic stenosis at high surgical risk (STS-PROM >8%) 1
• Elderly patients (>80 years) 1
• Patients with significant comorbidities making surgery high-risk 1
• Patients with hostile chest anatomy or porcelain aorta 1

3. Balloon Aortic Valvuloplasty (BAV)

BAV has limited indications:

• Bridge to definitive SAVR or TAVI in hemodynamically unstable patients 1
• Bridge to decision when the contribution of AS to symptoms remains unclear 1
• Patients requiring urgent non-cardiac surgery who cannot undergo valve replacement immediately 2

4. Medical Management

Medical therapy has no role in treating the stenotic valve itself but may be used to manage symptoms while awaiting definitive treatment:

• Diuretics for pulmonary congestion (with caution) 2
• Avoid vasodilators (nitrates, ACE inhibitors, ARBs) due to risk of significant hypotension in severe AS 2, 3
• Avoid beta-blockers which may worsen the situation by reducing heart rate 2

Decision Algorithm for Treatment Selection

1. Assess surgical risk:

   • Low risk (STS-PROM <4%): SAVR preferred, especially in younger patients (<65 years)
   • Intermediate risk (STS-PROM 4-8%): Either SAVR or TAVI based on patient factors
   • High risk (STS-PROM >8%): TAVI preferred

2. Consider age:

   • <65 years: SAVR preferred
   • 65-75 years: SAVR generally preferred, but TAVI reasonable
   • 75-80 years: Either SAVR or TAVI based on other factors

   • 80 years: TAVI preferred

3. Evaluate anatomical factors:

   • Bicuspid valve: SAVR may be preferred
   • Porcelain aorta: TAVI preferred
   • Small annulus (<21mm): TAVI may be preferred
   • Severe calcification of aorta/annulus: Treatment depends on pattern

4. Consider comorbidities:

   • Need for concomitant cardiac surgery: SAVR preferred
   • Frailty: TAVI preferred
   • Severe lung disease: TAVI preferred
   • End-stage renal disease: TAVI may be preferred

Timing of Intervention

For symptomatic severe aortic stenosis, prompt intervention is crucial as:

• Without treatment, average survival is reduced to 2-3 years after symptom onset 1
• Mortality rates at 1,2, and 5 years in non-operated symptomatic patients are 67%, 56%, and 38%, respectively, compared to 94%, 93%, and 90% in those who undergo valve replacement 4
• A recent study showed that 54.7% of patients with symptomatic severe AS who did not receive AVR died within 1 year 5

Special Considerations

1. Low-flow, low-gradient severe AS with reduced LVEF:

   • Dobutamine stress echocardiography recommended to confirm true severe AS 1
   • AVR recommended if true severe AS is confirmed 1

2. Low-flow, low-gradient severe AS with preserved LVEF:

   • Additional testing (CT, stress echocardiography) often needed to confirm severity 1
   • Intervention should be considered if AS is confirmed as severe 1

3. Non-cardiac surgery in patients with severe AS:

   • For symptomatic patients: AVR should be performed before elective non-cardiac surgery 1
   • For asymptomatic patients with preserved LVEF: May proceed with low-risk non-cardiac surgery with careful monitoring 1, 2

Pitfalls to Avoid

1. Delaying intervention in symptomatic patients:

   • Many patients (74.4%) with severe symptomatic AS are not referred for AVR despite clear indications 5
   • Misclassification of symptoms or AS severity is common and leads to inappropriate conservative management 5

2. Inappropriate medical management:

   • Using vasodilators in severe AS can cause dangerous hypotension 2, 3
   • No medical therapy has been shown to slow progression or improve outcomes in severe AS 1

3. Incomplete evaluation:

   • Failure to involve a multidisciplinary Heart Team in decision-making 1
   • Inadequate assessment of surgical risk and anatomical factors that influence treatment choice

The evidence clearly demonstrates that prompt intervention with either SAVR or TAVI in patients with severe symptomatic aortic stenosis significantly improves survival and quality of life compared to conservative management.