Valvular Heart Disease Aortic Stenosis



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Valvular Heart Disease Aortic Stenosis


Aortic Stenosis

  • Etiology

  • Physical Examination

  • Assessing Severity

  • Natural History

  • Prognosis

  • Timing of Surgery



Common Clinical Scenarios



Innocent Murmurs

  • Common in asymptomatic adults

  • Characterized by

    • Grade I – II @ LSB
    • Systolic ejection pattern


An 83 year old man with exertional dyspnea

  • Previously well

  • Gradual onset Class 2/4 dyspnea

  • Occasional lightheadedness with exertion

  • O/E: 2/6 ejection murmur



An 83 year old man with exertional dyspnea

  • Is there significant valvular heart disease?

  • Which valve?

  • Is the valve playing a role in his dyspnea?

  • How do you distinguish AV sclerosis from stenosis?

  • What are the clinical signs of severe AS?

  • What tests are appropriate?

  • When is surgery indicated?



Aortic Stenosis: Symptoms

  • Cardinal Symptoms

    • Chest pain (angina)
      • Reduced coronary flow reserve
      • Increased demand-high afterload
    • Syncope/Dizziness (exertional pre-syncope)
      • Fixed cardiac output
      • Vasodepressor response
    • Dyspnea on exertion & rest
    • Impaired exercise tolerance
  • Other signs of LV failure

    • Diastolic & systolic dysfunction


Common Murmurs and Timing (click on murmur to play)

  • Systolic Murmurs

  • Aortic stenosis

  • Mitral insufficiency

  • Mitral valve prolapse

  • Tricuspid insufficiency

  • Diastolic Murmurs

  • Aortic insufficiency

  • Mitral stenosis



Aortic Stenosis: Physical Findings



Aortic Stenosis: Physical Findings

  • Intensity DOES NOT predict severity

  • Presence of thrill DOES NOT predict severity

  • “Diamond” shaped, harsh, systolic crescendo-decrescendo

  • Decreased, delay & prolongation of pulse amplitude

  • Paradoxical S2

  • S4 (with left ventricular hypertrophy)

  • S3 (with left ventricular failure)



Recognizing Aortic Stenosis



An 83 year old man with exertional dyspnea



Aortic Stenosis - Etiology

  • Young patient think congenital

    • Bicuspid
      • 2% population
      • 3:1 male:female distribution
      • Co-existing coarctation 6% of patients


Aortic Stenosis: Etiology

  • Congenital bicuspid valve is the most common abnormality

  • Rheumatic heart disease and degeneration with calcification are found as well



Bicuspid Aortic Valve





Severity of Stenosis

  • Normal aortic valve area 2.5-3.5 cm2

  • Mild stenosis 1.5-2.5 cm2

  • Moderate stenosis 1.0-1.5 cm2

  • Severe stenosis < 1.0 cm2

  • Onset of symptoms

    • 0.9 cm2 with CAD
    • 0.7 cm2 without CAD


Echocardiogram

  • Etiology

  • Valve gradient and area

  • LVH

  • Systolic LV function

  • Diastolic LV function

  • LA size

  • Concomitant regional wall motion abnormalities

  • Coarctation associated with bicuspid AV





Figure 1: Principles of the Use of Doppler Ultrasonography and the Continuity Equation in Estimating Aortic-Valve Area. For blood flow (A1 x V1) to remain constant when it reaches a stenosis (A2), velocity must increase to V2. Doppler examination of the stenosis detects the increase in velocity, which can be used to calculate the aortic-valve gradient or to solve the continuity equation for A2. A denotes area, and V velocity



Aortic Stenosis: Prognosis



Natural History of Aortic Stenosis

  • Heart failure reduces life expectancy to less than 2 years

  • Angina and syncope reduce life expectancy between 2 and 5 years

  • Rate of progression  @ 0.1 cm2/year



Operative mortality of AVR in the elderly

  • ~ 4-24%/year

  • Risk factors for operative mortality

    • Functional class
    • Lack of sinus rhythm
    • HTN
    • Pre-existing LV dysfunction


Prosthetic Heart Valves



Caged-Ball Valve



Disc Valve



Bio-prosthetic Valve



Prosthetic Valves

  • MECHANICAL

    • Durable
    • Large orifice
    • High thromboembolic potential
    • Best in Left Side
    • Chronic warfarin therapy



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