What is the management plan for Surgical Aortic Valve Replacement (SAVR)?

Management of Surgical Aortic Valve Replacement (SAVR)

Surgical aortic valve replacement (SAVR) remains the standard intervention for severe aortic stenosis in patients with low surgical risk, those requiring concurrent cardiac procedures, or when anatomical factors make TAVR unsuitable.

Patient Selection for SAVR

SAVR is preferred over TAVI/TAVR in the following scenarios 1:

• Age-based considerations:

  • Patients aged <65 years or with life expectancy >30 years
  • Patients aged 65-80 years with low surgical risk after shared decision-making

• Anatomical factors favoring SAVR:

  • Aortic root anatomy unfavorable for TAVI (excessive calcification, annulus size out of range)
  • Need for concurrent cardiac procedures:
    • Multi-vessel coronary artery disease requiring CABG
    • Other valve pathology requiring intervention
    • Aortic root or ascending aorta pathology
    • Endocarditis

• Risk stratification:

  • Low surgical risk (STS-PROM <3-4%)
  • Absence of frailty and major comorbidities
  • No procedure-specific impediments

Preoperative Assessment

A comprehensive preoperative evaluation should include:

1. Echocardiographic assessment:

   • Confirm AS severity (valve area, mean gradient, peak velocity)
   • Evaluate LV function and dimensions
   • Assess for concomitant valve disease

2. Risk assessment:

   • Calculate surgical risk using validated scores (STS-PROM, EuroSCORE)
   • Evaluate frailty and functional status
   • Assess comorbidities that may impact surgical outcomes

3. Heart Team discussion:

   • Multidisciplinary evaluation of surgical candidacy
   • Shared decision-making with patient regarding SAVR vs. TAVI

Surgical Approach and Technique

The standard surgical approach involves:

1. Median sternotomy (traditional approach)

   • Alternative minimally invasive approaches may be considered in selected cases

2. Cardiopulmonary bypass with cardioplegic arrest

3. Valve selection:

   • Mechanical valve: preferred for younger patients (<65 years) with longer life expectancy
   • Bioprosthetic valve: preferred for older patients (>65 years) or those with contraindications to anticoagulation

4. Concomitant procedures as indicated:

   • CABG
   • Other valve repair/replacement
   • Aortic root/ascending aorta replacement

Postoperative Management

1. Immediate postoperative care:

   • Standard ICU monitoring
   • Early extubation when appropriate
   • Optimization of hemodynamics
   • Pain management

2. Anticoagulation/antiplatelet therapy:

   • Mechanical valves: Lifelong warfarin (target INR based on valve type/position)
   • Bioprosthetic valves: Aspirin (75-100 mg daily) indefinitely; consider warfarin for 3-6 months

3. Postoperative complications to monitor:

   • Bleeding
   • Infection
   • Arrhythmias (particularly atrial fibrillation)
   • Paravalvular leak
   • Prosthetic valve dysfunction

Follow-up and Surveillance

Regular follow-up is essential 1:

1. Initial follow-up:

   • 1-2 weeks after discharge: wound check, medication adjustment
   • 1-3 months: clinical assessment and echocardiography

2. Long-term surveillance:

   • Annual clinical assessment
   • Echocardiography:
     • Baseline at 3-6 months post-SAVR
     • Then every 3 years if no complications or concerns
     • More frequent if abnormalities detected

3. Monitoring for:

   • Prosthetic valve function
   • LV size and function
   • Development of symptoms
   • Complications (paravalvular leak, prosthetic valve endocarditis, thrombosis)

Special Considerations

1. Asymptomatic severe AS:

   • Recent evidence from the AVATAR trial 2 supports early SAVR in asymptomatic patients with severe AS and normal LV function
   • Early intervention may prevent LV hypertrophy and improve long-term outcomes 3

2. Valve-in-valve procedures:

   • For failed bioprosthetic valves, TAVI may be considered as an alternative to redo SAVR
   • However, in younger patients or those with long life expectancy, redo SAVR may still be preferred 4

3. Aortic regurgitation:

   • SAVR remains the standard intervention for severe AR 1
   • Intervention indicated for:
     • Symptomatic severe AR regardless of LV function
     • Asymptomatic severe AR with LV dysfunction (LVEF <50-55%) or significant LV dilation

Pitfalls and Caveats

1. Avoid delayed intervention in patients with severe symptomatic AS, as mortality increases significantly without valve replacement

2. Consider patient-specific factors when selecting valve type:

   • Mechanical valves require lifelong anticoagulation but offer greater durability
   • Bioprosthetic valves avoid long-term anticoagulation but have limited durability

3. Recognize that SAVR and TAVI are complementary rather than competing therapies:

   • SAVR remains the standard for younger, lower-risk patients
   • TAVI is preferred for older, higher-risk patients

4. Monitor for valve degeneration in patients with bioprosthetic valves, particularly younger patients who may require reintervention

5. Be vigilant for paravalvular leaks which may require reintervention if severe

By following these guidelines for SAVR management, clinicians can optimize outcomes for patients with severe aortic stenosis requiring surgical intervention.