What is the clinical significance and management of Faget's sign in relation to aortic regurgitation?

Faget's Sign in Aortic Regurgitation

Faget's sign, characterized by a relative bradycardia despite fever, is not a typical clinical finding in aortic regurgitation and has no established clinical significance in this condition based on current guidelines.

Understanding Faget's Sign and Aortic Regurgitation

Faget's sign (pulse-temperature dissociation) is classically associated with certain infectious diseases like yellow fever and typhoid fever, not with valvular heart conditions such as aortic regurgitation (AR). The current guidelines on aortic regurgitation management from the European Society of Cardiology and American College of Cardiology do not mention Faget's sign as a relevant clinical finding in AR 1.

Key Clinical Findings in Aortic Regurgitation

Instead of Faget's sign, the following are important clinical manifestations of AR:

• Wide pulse pressure
• Bounding peripheral pulses
• Systolic hypertension
• Diastolic murmur
• Water-hammer pulse (Corrigan's pulse)
• Head bobbing (de Musset's sign)
• Pistol shot sounds over femoral arteries (Traube's sign)
• Quincke's pulse (capillary pulsations)

Diagnostic Approach for Aortic Regurgitation

The primary diagnostic modality for AR is echocardiography, which provides critical information about:

• Etiology of AR
• Severity assessment
• Impact on left ventricular size and function
• Hemodynamic consequences 1, 2

Severity Assessment Criteria

Severe AR is defined by:

• Vena contracta >0.6 cm
• Regurgitant volume ≥60 mL/beat
• Effective regurgitant orifice area (EROA) ≥0.3 cm²
• Holodiastolic flow reversal in descending aorta
• Pressure half-time <200 ms
• Regurgitant fraction ≥50% on CMR 1

Management Considerations

Management of AR should focus on:

1. Regular monitoring:

   • Mild AR: Every 3-5 years
   • Moderate AR: Every 1-2 years
   • Severe asymptomatic AR: Every 6-12 months 1

2. Medical therapy:

   • Afterload reduction with vasodilators
   • ACE inhibitors or dihydropyridine calcium channel blockers for hypertensive patients
   • Guideline-directed heart failure therapy for symptomatic patients with LV dysfunction 1

3. Surgical intervention is indicated for:

   • Symptomatic severe AR
   • Asymptomatic severe AR with:
     • LVEF <50-55%
     • LVESD >50 mm or >25 mm/m²
     • LVEDD >65 mm
     • Progressive decline in LVEF 1, 2

Special Considerations

Exercise Testing in AR

Exercise echocardiography can be valuable to:

• Reveal symptoms in apparently asymptomatic patients with severe AR
• Assess left ventricular contractile reserve (lack of contractile reserve defined as <5% increase in LVEF predicts LV dysfunction) 2

Mixed Valve Disease

When AR coexists with aortic stenosis:

• The assessment of each individual lesion becomes more challenging
• Monitoring should occur every 6 months as half of patients become symptomatic within 1 year
• Moderate mixed disease has poorer prognosis than moderate AS or AR alone 2, 3

Conclusion

While Faget's sign is not a recognized clinical finding in aortic regurgitation, clinicians should focus on established diagnostic criteria and management strategies outlined in current guidelines. The presence of AR requires careful monitoring and timely intervention based on symptoms, left ventricular function, and chamber dimensions to prevent irreversible cardiac damage and adverse outcomes.