What are the management options for aortic stenosis?

Management of Aortic Stenosis

The management of aortic stenosis requires valve intervention (TAVR or SAVR) for all symptomatic patients with severe aortic stenosis, with the choice between transcatheter and surgical approaches determined primarily by age, surgical risk, and anatomical considerations. 1, 2

Diagnosis and Classification of Aortic Stenosis

Defining Severe Aortic Stenosis

• Valve area <1.0 cm²
• Mean gradient ≥40 mmHg
• Maximum velocity ≥4 m/s

Special Considerations

• Low-flow, low-gradient AS: Requires dobutamine stress echocardiography to distinguish true-severe from pseudo-severe AS 1
• Asymptomatic severe AS: Regular monitoring every 6 months with echocardiography 2
• Moderate AS: Monitoring every 12 months 2

Management Algorithm

1. Symptomatic Severe Aortic Stenosis

• Intervention is mandatory for patients with symptoms (dyspnea, heart failure, angina, syncope) and severe AS 1
• Urgent intervention required for patients with cardiogenic shock 2

2. Asymptomatic Severe Aortic Stenosis

• Intervention recommended when:

  • Left ventricular ejection fraction (LVEF) <50-55% 1, 2
  • Rapid progression (velocity increase >0.3 m/s/year) 1
  • Very severe AS (velocity >5 m/s) 1
  • Abnormal exercise test (symptoms, blood pressure drop) 2
  • Elevated BNP levels 1

• Recent evidence: Early TAVR in asymptomatic severe AS showed superiority over clinical surveillance in reducing death, stroke, or unplanned cardiovascular hospitalizations 3

3. Choice Between TAVR and SAVR

Age-based approach:

• <65 years: SAVR preferred 1, 2, 4
• 65-75 years: SAVR generally preferred over TAVR 1, 2
• 75-80 years: Either SAVR or TAVR (individualized) 1
• >80 years: TAVR preferred 1, 2

Surgical risk approach:

• STS-PROM >8%: TAVR preferred 1, 2
• STS-PROM ≤8%: Either SAVR or TAVR appropriate 1

Anatomical considerations:

• Bicuspid valve: SAVR may be preferred 2, 4
• Hostile calcium: Heart Team decision 4
• Need for concomitant procedures (CABG, mitral valve surgery): SAVR 1

Valve Selection for SAVR

• <50 years: Mechanical valve 1
• 50-60 years: Mechanical valve preferred over bioprosthetic 1
• 60-65 years: Either mechanical or bioprosthetic 1
• >65 years: Bioprosthetic valve 1

Medical Management

For Patients Awaiting Intervention

• Hypertension management: Start antihypertensives at low doses and titrate gradually 2
  • ACE inhibitors/ARBs may be advantageous
  • Use beta-blockers for patients with reduced EF, prior MI, arrhythmias, or angina
  • Use diuretics cautiously in patients with small LV chambers

For Patients Not Candidates for Intervention

• Balloon aortic valvuloplasty: May be considered as a bridge to definitive therapy 2
• Palliative care: For patients with life expectancy <1 year or <25% chance of survival with benefit at 2 years 1

Monitoring and Follow-up

Post-Intervention Follow-up

• Echocardiography to evaluate:
  • Maximum aortic velocity
  • Mean aortic valve gradient
  • Aortic valve area
  • Paravalvular and valvular regurgitation
  • LV function and geometry 1

Long-term Considerations

• Bioprosthetic valve durability: Concern for younger patients, with SAVR having more proven long-term durability than TAVR 4
• Valve thrombosis and deterioration: Monitor for signs of valve failure (3.3% for TAVR and 3.8% for SAVR at 5 years) 5

Special Scenarios

Aortic Stenosis with Heart Failure

• Optimization of guideline-directed medical therapy may be challenging 6
• Multidisciplinary management involving heart failure specialists is crucial 6
• Dedicated pre-procedural assessment and careful post-procedural follow-up are essential 6

Moderate Aortic Stenosis with LV Dysfunction

• Current guidelines do not recommend AVR for moderate AS with LV dysfunction 1
• Ongoing trials (TAVI UNLOAD) are evaluating whether early TAVR might be beneficial in this population 1

Common Pitfalls and Caveats

1. Misdiagnosis of symptom status: Exercise testing can unmask symptoms in supposedly asymptomatic patients
2. Underestimating severity in low-flow states: Low-dose dobutamine stress echocardiography is essential
3. Delaying intervention in symptomatic patients: Once symptoms develop, mortality increases dramatically without intervention
4. Overestimating surgical risk: STS score alone may not capture all relevant factors; comprehensive assessment by Heart Team is crucial
5. Neglecting heart failure management: Patients with AS and heart failure require specialized care before and after valve intervention

By following this structured approach to aortic stenosis management, clinicians can optimize outcomes by ensuring timely and appropriate interventions based on patient characteristics and disease severity.