Aortic Regurgitation

See Also

Heart Valve Disorder

Pathophysiology

Cardiovascular effects of chronic Aortic Regurgitation
1. Increased Stroke Volume
2. Systolic Hypertension
3. High Pulse Pressure (due to low diastolic pressure)
4. Increased Afterload
Outcome
1. Left ventricular dilatation and hypertrophy
2. Left Ventricular Failure
3. Increased myocardial oxygen demand

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
1. Systemic Lupus Erythematosus
2. Marfan's Syndrome
3. Turner's Syndrome
4. Pseudoxanthoma elasticum
5. Ankylosing Spondylitis
6. Ehlers-Danlos Syndrome
7. Polymyalgia Rheumatica

Causes
Acute

Bacterial Endocarditis or other valvular infection
Aortic Dissection
Chest Trauma
Myxomatous aortic valve

Predisposing Factors

Bicuspid aortic valve

Symptoms

Asymptomatic until severe Left Ventricular Failure
Initial
1. Decreased functional capacity
2. Weakness or Fatigue
Left Ventricular Failure symptoms
1. Dyspnea on exertion
2. Orthopnea
3. Anginal pain

Signs

Early Diastolic Murmur
1. Characteristics
  1. Initial: High-pitched blowing decrescendo murmur
  2. Later: Lower pitched, loud, and throughout diastole
2. Murmur localizes to sternal border
  1. Right second interspace
  2. Left third interspace
Accentuated systolic activity
1. Accentuated precordial thrust at the apex
2. Accentuated A2 heart sound
Wide Pulse Pressure
1. High systolic Blood Pressure due to increase Stroke Volume
2. Low diastolic pressure from aortic run-off
3. Collapsing Pulse (Water-Hammer Pulse)
  1. Rapid systolic upstroke and rapid diastolic downstroke
Large Artery Findings
1. Pistol-Shot Sound (femoral artery or Carotid Artery)
  1. Loud, booming sound with systole when auscultating femoral artery
2. Duroziez's Sign (femoral artery)
  1. Auscultation of femoral artery
  2. Systolic Murmur when femoral artery compressed proximally
  3. Diastolic Murmur when femoral artery compressed distally
3. Corrigan's Pulse (Carotid Artery)
  1. Jerky Carotid Artery pulse (strong onset that rapidly diminishes)
4. Pulsus Bisferiens (Carotid Artery)
  1. Double peak pulse (two peaks in systole) seen in severe Aortic Regurgitation
Synchronous Body Movements with Cardiac Cycle
1. Musset's Sign of DeMusset's Sign
  1. Head bobbing in rhythm with pulse
2. Landolfi's Sign
  1. Alternating Pupil Dilation and constriction
3. Becker Sign
  1. Accentuated Retinal artery pulsations
4. Lighthouse Sign
  1. Alternating forehead and face blanching and Flushing
5. Quincke's Pulse
  1. Gentle pressure at nail bed applied
  2. Nail bed alternates between blanching and erythema
6. Abdominal Organ Pulsations
  1. Rosenbach's Sign (liver pulsations)
  2. Gerhardt's Sign (enlarged Spleen pulsations)
Hill's Sign
1. Popliteal systolic pressure > brachial systolic pressure (>20 mmHg)
2. Interpretation: Mild AR >20 mmHg, moderate AR >40 mmHg, severe AR >60 mmHg
Mayne's sign
1. Listed for historical purpose only
2. Diastolic BP drops more than 15 mmHg with arm raised
3. Not pathognomonic for Aortic Insufficiency
4. Abbas (1987) South Med J 80:1051-2 [PubMed]

Imaging
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
1. Left ventricular dilatation
2. Left Ventricular ejection fraction

Monitoring

Echocardiogram yearly or earlier for change in symptoms

Management

SBE Prophylaxis
Medical therapy: Afterload reduction with vasodilators
1. May delay surgical intervention 2 to 3 years
2. Agents

Management
Aortic Valve Replacement

General
1. Early surgical intervention results in better outcome
2. Goals of surgical intervention
  1. Symptoms more than mild
  2. Keep Ejection fraction >55%
  3. Keep end systolic dimension <55 mm
Class I AHA Indications for Aortic Valve Replacement
1. NYHA Class III or IV Heart Failure symptoms
2. NYHA Class II Symptoms with LVEF >50%, but decline
  1. Progressive LV dilatation
  2. Decreasing LV ejection fraction on serial echo
  3. Decreasing Exercise tolerance on stress testing
3. Canadian Heart Association Class II Angina
4. Mild to moderate LV dysfunction (LVEF 25 to 49%)
5. Moderate to severe Aortic Regurgitation and Pre-op
  1. Coronary Artery Bypass Graft
  2. Other valvular surgery
Class IIA AHA Indications for Aortic Valve Replacement
1. NYHA Class II Symptoms with stable LVEF >50%
2. Severe left ventricular dilatation
  1. End diastolic diameter >75 mm
  2. End systolic diameter >55 mm
Class IIB AHA Indications for Aortic Valve Replacement
1. Severe Left Ventricular Dysfunction (LVEF <25%)
2. Moderate and progressive left ventricular dilatation
  1. End diastolic diameter 70 to 75 mm
  2. End systolic diameter 50 to 55 mm

Course of Chronic Aortic Regurgitation

Asymptomatic with LV Ejection Fraction >50%
1. Progression to symptoms: <6% per year
2. Progression to LV Dysfunction: <3.5% per year
3. Sudden death risk: 0.2% per year
Asymptomatic with LV Ejection Fraction <50%
1. Progression to symptoms: >25% per year
Symptomatic with LV Ejection Fraction <50%
1. Mortality: 10% per year

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]