What is the treatment approach for aortic stenosis?

Treatment Approach for Aortic Stenosis

Surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR) is the only effective therapy for symptomatic patients with severe aortic stenosis, while management of asymptomatic patients requires individualized risk stratification. 1

Diagnosis and Assessment

• Echocardiography is the cornerstone of evaluation, sufficient for guiding management in 65-70% of patients 1
• Multimodality imaging may be required in 25-30% of cases where echocardiographic findings are uncertain 1
• Severe AS is defined by:
  • Aortic valve area (AVA) < 1.0 cm²
  • Mean pressure gradient > 40 mmHg
  • Peak velocity > 4 m/s 1

Treatment Algorithm Based on Symptom Status

Symptomatic Severe AS

• Valve replacement (SAVR or TAVR) is strongly recommended for all symptomatic patients with severe AS 1
• Common symptoms include angina, dyspnea, and syncope 2
• Without treatment, average survival is reduced to 2-3 years once symptoms develop 1
• Decision between SAVR vs. TAVR depends on:
  • Surgical risk assessment (STS-PROM score)
  • Patient age and frailty
  • Anatomical considerations
  • Comorbidities 1

Asymptomatic Severe AS

• Watchful waiting with regular monitoring is generally recommended 3
• Intervention is appropriate in specific high-risk scenarios:
  • Very severe AS (AVA ≤ 0.75 cm² with peak velocity ≥ 4.5 m/s or mean gradient ≥ 50 mmHg) 1
  • Positive exercise test (development of symptoms or abnormal blood pressure response) 1
  • Rapid progression of stenosis (increase in peak velocity > 0.3 m/s/year) 1
  • Severe valve calcification 1
  • Left ventricular ejection fraction < 50% 1
  • High-risk profession (e.g., airline pilot) or lifestyle (competitive athlete) 1

Surgical Risk Assessment for Intervention Type

• Low surgical risk (STS-PROM <4%): SAVR generally recommended, especially in younger patients 1, 4
• Intermediate surgical risk (STS-PROM 4-8%): Either SAVR or TAVR appropriate based on patient factors 1
• High surgical risk (STS-PROM >8%): TAVR generally preferred 1
• Additional factors favoring TAVR:
  • Advanced age (>75 years) 4
  • Frailty 1
  • Porcelain aorta or hostile chest 1
  • Significant comorbidities (lung/liver disease, malignancy) 1

Special Considerations

Low-Flow, Low-Gradient AS

• Requires confirmation of true stenosis severity using:
  • Dobutamine stress echocardiography (DSE)
  • Multi-slice computed tomography (MSCT) 1
• Intervention recommended if true severe AS is confirmed and flow reserve is present 1

Concomitant Cardiac Conditions

• For patients with severe AS and coronary artery disease:
  • SAVR plus CABG is appropriate for most patients 1
  • TAVR plus PCI may be appropriate for intermediate/high-risk patients with less complex coronary disease 1
• For severe AS with other valve disease:
  • Surgical approach generally preferred unless high surgical risk 1

Medical Management

• No medical therapy has been shown to improve survival or delay the need for valve replacement in severe AS 5
• Management of concurrent conditions:
  • Hypertension: Careful blood pressure control while avoiding hypotension 2, 3
  • Heart failure: Cautious use of diuretics; nitrates may be reasonable but avoid hypotension 2
  • For hypotensive patients: Use vasopressors at lowest effective dose 2

Follow-up Recommendations

• Asymptomatic severe AS: Echocardiography every 6-12 months 3
• Moderate AS: Echocardiography every 1-2 years 3
• Mild AS: Echocardiography every 3-5 years 3
• Patient education about prompt reporting of symptoms is crucial 3

Pitfalls and Caveats

• Symptoms may be difficult to ascertain in elderly patients due to comorbidities or reduced mobility 1
• Exercise testing can unmask symptoms in apparently asymptomatic patients 1
• Avoid hypotension in AS patients as it can lead to clinical decompensation 2
• Medical futility should be considered in patients with life expectancy <1 year or severe dementia 1
• Palliative balloon aortic valvuloplasty may be considered in select patients with limited life expectancy 1