When should a patient with mild stenosis be referred to cardiology?

When to Refer Patients with Mild Aortic Stenosis to Cardiology

Patients with mild aortic stenosis should be referred to cardiology when they develop symptoms, have reduced left ventricular ejection fraction (<60%), or show evidence of rapid progression of stenosis severity. 1, 2

Risk Stratification for Patients with Mild Stenosis

Symptoms and Clinical Presentation

• Patients with mild stenosis who develop symptoms (NYHA class II-IV) should be promptly referred to cardiology, as symptom severity is independently associated with increased mortality 2
• Patients with severe ongoing ischemia, major arrhythmias, or hemodynamic instability require urgent cardiology referral within the first hour 1
• Even mild symptoms (NYHA class II) in patients with mild stenosis are associated with increased risk of adverse events and warrant cardiology evaluation 2

Cardiac Function Assessment

• Left ventricular ejection fraction (LVEF) is a strong predictor of outcomes - patients with LVEF <60% have increased mortality risk and should be referred 2, 1
• Resting echocardiography is recommended for all patients to assess:
  • Regional wall motion abnormalities suggestive of CAD
  • LVEF measurement for risk stratification
  • Evaluation of diastolic function 1

Disease Progression Indicators

• Refer patients showing signs of rapid progression:
  • Moderate-severe valve calcification
  • Gradient increase >10 mmHg per year
  • Aortic jet velocity increase >0.4 m/s per year 3
• Patients with mild stenosis and established coronary artery disease (CAD) have a significantly higher risk of cardiac mortality (62% increased risk) and should be referred 4

Diagnostic Evaluation Before Referral

Non-invasive Testing

• Non-invasive functional imaging for myocardial ischemia or coronary CTA is recommended as the initial test for diagnosing CAD in symptomatic patients 1
• Functional imaging is recommended if coronary CTA has shown CAD of uncertain functional significance 1
• In asymptomatic patients with mild stenosis, serial Doppler echocardiography is recommended every 3-5 years 5

Risk Assessment Tools

• CAD-RADS classification can help determine referral need:
  • CAD-RADS 3 (50-69% stenosis): Consider functional assessment 1
  • CAD-RADS 4 (70-99% stenosis): Consider invasive coronary angiography (ICA) or functional assessment 1

Special Considerations

Coexisting Coronary Artery Disease

• Patients with mild stenosis and established CAD should be referred to cardiology due to their 62% higher risk of cardiac mortality 4
• For patients with mild stenosis undergoing CABG, concomitant AVR may be considered for "rapid progressors" if life expectancy exceeds 5 years 3
• Pathophysiological links between degenerative calcific AS and CAD suggest an active, progressive process with shared risk factors 3

High-Risk Features

• Patients with high-risk clinical profiles and symptoms inadequately responding to medical treatment should be referred for ICA with invasive physiological guidance (FFR) 1
• Asymptomatic patients with high event risk on non-invasive risk stratification should be referred for ICA with invasive physiological guidance 1
• Patients with FFR ≤0.75 or CFR ≥2.0 have hemodynamically significant stenosis that may benefit from intervention 1

Follow-up Recommendations

• For asymptomatic patients with mild stenosis without high-risk features:

  • Echocardiography every 3-5 years 5
  • Statin therapy should be considered as it may improve long-term prognosis 4
  • Educate patients about the importance of promptly reporting new symptoms 5

• For patients with mild stenosis and intermediate-risk features:

  • More frequent monitoring with echocardiography (1-2 years) 5
  • Consider stress testing to evaluate for inducible ischemia 1

• Cardiology referral is recommended for all patients with:

  • Symptomatic mild stenosis
  • Left ventricular systolic dysfunction (LVEF <60%)
  • Evidence of rapid progression
  • Coexisting significant CAD 5, 2