What is the recommended surveillance and management approach for patients with aortic stenosis?

Surveillance Protocol for Aortic Stenosis

For patients with aortic stenosis, surveillance should be conducted using transthoracic echocardiography (TTE) with frequency determined by disease severity: every 3-5 years for mild AS, every 1-2 years for moderate AS, and every 6-12 months for severe asymptomatic AS. 1

Initial Evaluation

• When aortic stenosis is identified, a comprehensive assessment should include evaluation of aortic valve anatomy and function, aortic root dimensions, and ascending aorta diameters using TTE 1
• CCT (cardiac computed tomography) or CMR (cardiac magnetic resonance) is recommended to confirm TTE measurements, rule out aortic asymmetry, and determine baseline diameters for follow-up 1
• Assessment of the entire aorta is recommended at baseline when an aortic aneurysm is identified at any location 1
• When a thoracic aortic aneurysm (TAA) is identified, assessment of the aortic valve (especially for bicuspid aortic valve) is recommended 1

Surveillance Intervals Based on AS Severity

Mild Aortic Stenosis

• TTE every 3-5 years is recommended 2
• More frequent monitoring (every 1-2 years) is appropriate for patients with significant valve calcification 1

Moderate Aortic Stenosis

• TTE every 1-2 years is recommended 1, 2
• Annual assessment is recommended for patients with significant calcium burden 1
• Consider more frequent monitoring in patients with risk factors for rapid progression (severe valve calcification, rapid change in peak jet velocity, disproportionate LV hypertrophy) 1, 3

Severe Asymptomatic Aortic Stenosis

• TTE every 6-12 months is recommended 2
• Exercise testing/exercise stress echo may be valuable to unmask symptoms in apparently asymptomatic patients 1
• Consider serum BNP measurement as an additional tool for risk stratification 1

Special Considerations

• Patients with bicuspid aortic valves require surveillance of both the valve and the aorta due to associated aortopathy 1
• Apparently asymptomatic patients may subconsciously curtail their activities to avoid symptoms; carefully monitored exercise stress testing can confirm true asymptomatic status 4
• Multimodality imaging biomarkers (global longitudinal strain, T1 mapping indices, late gadolinium enhancement) may help identify subclinical LV decompensation in asymptomatic patients 1
• For patients with concomitant aortic stenosis and transthyretin cardiac amyloidosis, more aggressive surveillance may be warranted due to higher all-cause mortality 1

Post-Intervention Surveillance

After Surgical Aortic Valve Replacement

• TTE before discharge and yearly thereafter 1
• For patients with aortic root repair, TTE before discharge and yearly thereafter 1

After Transcatheter Aortic Valve Replacement (TAVR)

• TTE before discharge and at regular intervals thereafter (similar to surgical AVR) 5
• More frequent imaging may be necessary in younger patients who received TAVR, as long-term durability data are still emerging 5

Common Pitfalls to Avoid

• Underestimating the importance of regular surveillance in asymptomatic patients with severe AS, as sudden cardiac death can occur 4
• Failing to recognize that patients may unconsciously limit their activities to avoid symptoms 4
• Relying solely on symptoms without objective measurements of valve gradient and ventricular function 4
• Neglecting to assess the entire aorta when an aneurysm is identified at any location 1
• Using TTE alone for surveillance of aneurysms in the distal ascending aorta, aortic arch, or descending thoracic aorta (CMR or CCT is recommended) 1

By following these evidence-based surveillance protocols, clinicians can optimize the timing of interventions and improve outcomes for patients with aortic stenosis.