Cardiovascular Medicine Book

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Aortic StenosisAka: Valvular Aortic Stenosis

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  1. Etiology
    1. Congenital Bicuspid Valve (Most common)
      1. Twice as common in men
      2. Slow increase in stenosis (progressive sclerosis)
        1. Childhood: mild stenosis and asymptomatic
        2. Ages 20-40: moderate stenosis develops
        3. Over age 40: severe stenosis develops
    2. Atherosclerosis
      1. Normal tricuspid valve becomes rigid with age
      2. Develops over age 70
      3. Rarely severe
    3. Rheumatic Fever
      1. Slowly progressive stenosis
    4. Subacute Bacterial Endocarditis
  2. Symptoms
    1. Mild to Moderate stenosis
      1. Asymptomatic
    2. Severe Obstruction
      1. Syncope
      2. Exercise induced Angina
      3. Dyspnea on exertion to Dyspnea at rest
      4. Congestive Heart Failure
  3. Signs
    1. Classic Murmur
      1. Harsh crescendo-decrescendo Systolic Murmur
      2. Medium pitch
      3. Heard best at right upper sternum
      4. May also be heard at apex
    2. Mild aortic stenosis
      1. Loud ejection click (best heard at apex)
      2. Short, early Systolic Murmur
      3. Loud A2 heart sound (best heard at aortic area)
    3. Moderate aortic stenosis
      1. Ejection click (best heard at apex)
      2. Early Systolic Murmur (loudest at aortic area)
        1. Transmitted to Supraclavicular, Carotids, Apex
        2. Harsh
        3. Ends well before A2 heart sound
      3. Arterial Pulse altered
        1. Upstroke of the pulse has shudder, and is prolonged
      4. Apex impulse may be abnormal, accentuated
        1. Slightly sustained
        2. Presystolic shoulder ("a wave")
          1. Precedes major systolic impulse
      5. Systolic thrill may be palpated at base
    4. Severe aortic stenosis
      1. Ejection click NO longer present
      2. A2 heart sound is markedly diminished
      3. Systolic Murmur
        1. Variable loudness (may be quiet despite severity)
        2. Long, nearly holosystolic
        3. Harsh (especially at aortic area)
      4. Carotid pulse very abnormal
        1. Very slow and long upstroke
        2. Overall small quality to pulse
      5. Apical impulse abnormal
        1. Strong and sustained for all of systole
  4. Associated conditions
    1. AV Node Block (often concurrent with aortic stenosis)
    2. Aortic Coarctation
    3. Aortic Dissection
  5. Diagnosis
    1. Electrocardiogram (only abnormal in severe stenosis)
      1. Left Ventricular Hypertrophy
      2. T Wave reduction in leads I, avL, V5, V6
      3. Left Anterior Hemiblock or Left Bundle Branch Block
      4. Complete AV Block
    2. Chest XRay
      1. Apical Contour abnormal suggests large left ventricle
      2. Prominent ascending aorta
      3. Aortic valve calcification
    3. Echocardiogram
      1. Repeat every 2 years
      2. Can distinguish normal tricuspid valve from:
        1. Bicuspid valve
        2. Mildly obstructed valve
        3. Thickened, sclerotic valve
      3. Criteria for critical stenosis
        1. Valve area less than 0.8 cm2
        2. Gradient >50 mmHg
    4. Cardiac Catheterization (Angiogram)
  6. Differential Diagnosis
    1. Supravalvular aortic stenosis
    2. Membranous supravalvular aortic stenosis
    3. Hypertrophic Cardiomyopathy (IHSS)
    4. Mitral Regurgitation
  7. Management
    1. General
      1. SBE Prophylaxis
    2. Symptomatic and severe stenosis (>50 mmHg across valve)
      1. Avoid strenuous Exercise or activity
      2. Salt restriction
      3. Digoxin (Digitalis)
        1. Indicated for Congestive Heart Failure
      4. Diuretics
        1. Indicated for Congestive Heart Failure
        2. Use with caution (lowers LV filling pressure)
      5. Use Nitroglycerin only with caution
        1. Monitor Blood Pressure carefully
        2. Volume expansion may be required
      6. Use Beta Blockers with caution
        1. Risk of Congestive Heart Failure
      7. Surgical evaluation ASAP (risk of sudden death)
        1. May be indicated even if ejection fraction low
        2. Not effective if low EF and low valve gradient
        3. Carabello (2002) N Engl J Med 346:677
    3. Asymptomatic patients with severe aortic stenosis
      1. Surgical indications (guidelines up to 2005)
        1. Aortic valve gradient >75 mmHg
        2. Aortic valve orifice <0.8 to 0.9 cm2
      2. New data suggests surgery at earlier stage
        1. Aortic valve gradient >60 mmHg
        2. Aortic valve orifice <0.6 cm2
        3. Reference
          1. Nishimura (2005) Mayo Reviews Lecture, Rochester
  8. Monitoring
    1. Repeat echocardiogram every 2 to 5 years
  9. Prognosis
    1. Mild aortic Stenosis: Good (slow progression)
      1. Anticipate active and asymptomatic for 10-50 years
    2. Severe asymptomatic aortic stenosis
      1. At 5 years, 72% will die or have symptoms
      2. Recent data suggests sudden death rate is high
      3. Pellikka (2005) Circulation 111:3290
    3. Symptomatic Aortic stenosis: Poor prognosis
      1. Most patients will have symptom progression
      2. Anticipate death within 3 years in most patients
  10. References
    1. Kondos (1998) CMEA Medicine Review Lecture, San Diego
    2. Assi (1998) Postgrad Med 104(6):99
    3. Bonow (1998) Circulation 98:1949
    4. Carabello (1997) N Engl J Med 337(1):32
    5. Lester (1998) Chest 113:1109
    6. Shipton (2001) Am Fam Physician 63(11):2201

Aortic Valve Stenosis (C0003507)

Definition (MSH)A pathological constriction that can occur above (supravalvular stenosis), below (subvalvular stenosis), or at the AORTIC VALVE. It is characterized by restricted outflow from the LEFT VENTRICLE into the AORTA.
Definition (CSP)constriction in the opening of the aortic valve or of the supravalvular or subvalvular regions.
Definition (NCI)Narrowing of the orifice of the aortic valve or of the supravalvular or subvalvular regions.
Definition (NCI)Narrowing of the orifice of the aortic valve or of the supravalvular or subvalvular regions.
ConceptsDisease or Syndrome (T047)
EnglishAortic Stenosis, Aortic Valve Stenoses, Stenosed aortic valve, Valvular aortic stenosis
Spanishestenosis de la válvula aórtica, estenosis de la valvula aortica
CreditsDerived from the NIH UMLS (Unified Medical Language System)



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