II. Pathophysiology
- Cardiovascular effects of chronic Aortic Regurgitation
- Increased Stroke Volume
- Systolic Hypertension
- High Pulse Pressure (due to low diastolic pressure)
- Increased Afterload
- Outcome
- Left ventricular dilatation and hypertrophy
- Left Ventricular Failure
- Increased myocardial oxygen demand
III. Causes: Chronic
- Rheumatic Heart Disease (Rheumatic Fever)
- Congenital Heart Disease (e.g. bicuspid aortic valve)
- Aneurysm of Valsalva's sinus
- Aortitis (e.g. Syphilis)
- Weight loss medications (e.g. Dexfenfluramine)
- Collagen Vascular Disease or Connective Tissue Disease
IV. Causes: Acute
- Bacterial Endocarditis or other valvular infection
- Aortic Dissection
- Chest Trauma
- Myxomatous aortic valve
V. Predisposing Factors
- Bicuspid aortic valve
VI. Symptoms
- Asymptomatic until severe Left Ventricular Failure
- Initial
- Decreased functional capacity
- Weakness or Fatigue
- Left Ventricular Failure symptoms
VII. Signs
- Accentuated precordial thrust at the apex
- Early Diastolic Murmur
- Characteristics
- Initial: High-pitched blowing decrescendo murmur
- Later: Lower pitched, loud, and throughout diastole
- Murmur localizes to sternal border
- Right second interspace
- Left third interspace
- Characteristics
- Accentuated A2 heart sound
- Pistol-Shot Sound
- Collapsing Pulse
- High Pulse Pressure
- Duroziez's Sign
- Quincke's Pulse
- Gentle pressure at nail bed applied
- Nail bed alternates between blanching and erythema
- Musset's Signs (head bobbing)
- Mayne's sign
- Listed for historical purpose only
- Diastolic BP drops more than 15 mmHg with arm raised
- Not pathognomonic for Aortic Insufficiency
- Abbas (1987) South Med J 80:1051-2 [PubMed]
VIII. Radiology: Echocardiogram
- Small regurgitant aortic jet may be normal
- Assess aortic valve morphology
- Assess aortic root size
- Estimate Aortic Regurgitation severity
- Assess left ventricular size and function
- Left ventricular dilatation
- Left Ventricular ejection fraction
IX. Monitoring
- Echocardiogram yearly or earlier for change in symptoms
X. Management
- SBE Prophylaxis
- Medical therapy: Afterload reduction with vasodilators
- May delay surgical intervention 2 to 3 years
- Agents
XI. Management: Aortic Valve Replacement
-
General
- Early surgical intervention results in better outcome
- Goals of surgical intervention
- Symptoms more than mild
- Keep Ejection fraction >55%
- Keep end systolic dimension <55 mm
- Class I AHA Indications for Aortic Valve Replacement
- NYHA Class III or IV Heart Failure symptoms
- NYHA Class II Symptoms with LVEF >50%, but decline
- Progressive LV dilatation
- Decreasing LV ejection fraction on serial echo
- Decreasing Exercise tolerance on stress testing
- Canadian Heart Association Class II Angina
- Mild to moderate LV dysfunction (LVEF 25 to 49%)
- Moderate to severe Aortic Regurgitation and Pre-op
- Coronary Artery Bypass Graft
- Other valvular surgery
- Class IIA AHA Indications for Aortic Valve Replacement
- NYHA Class II Symptoms with stable LVEF >50%
- Severe left ventricular dilatation
- End diastolic diameter >75 mm
- End systolic diameter >55 mm
- Class IIB AHA Indications for Aortic Valve Replacement
- Severe Left Ventricular Dysfunction (LVEF <25%)
- Moderate and progressive left ventricular dilatation
- End diastolic diameter 70 to 75 mm
- End systolic diameter 50 to 55 mm
XII. Course of Chronic Aortic Regurgitation
- Asymptomatic with LV Ejection Fraction >50%
- Progression to symptoms: <6% per year
- Progression to LV Dysfunction: <3.5% per year
- Sudden death risk: 0.2% per year
- Asymptomatic with LV Ejection Fraction <50%
- Progression to symptoms: >25% per year
- Symptomatic with LV Ejection Fraction <50%
- Mortality: 10% per year
XIII. References
- Kondos (1998) CMEA Medicine Review Lecture, San Diego
- Assi (1998) Postgrad Med 104(6):99-110
- Bonow (1998) Circulation 98:1949-84 [PubMed]
- Carabello (1997) N Engl J Med 337(1):32-41 [PubMed]
- Cheitlin (2001) Am Fam Physician 64(10):1709-14 [PubMed]
- Shipton (2001) Am Fam Physician 63(11):2201-8 [PubMed]