Exam

Heart Murmur

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Heart Murmur, Heart Murmur Interpretation

  • Physiology
  1. Ventricles fill most rapidly in the first third of diastole
    1. Aortic Regurgitation murmur is loudest in early diastole
    2. Mitral Stenosis murmur is also loudest in early diastole (with a slight delay for mitral valve opening)
  2. Ventricles empty most rapidly in the first third of systole
    1. However, the Aortic Stenosis murmur is a crescendo decrescendo Systolic Murmur (increases, peaks and decreases)
  • Images
  1. Cardiac Cycle Volumes and Pressures (Wiggers Diagram)
    1. cvCardiacCycleWiggers.png
  • Exam
  1. Characteristics
    1. Identify beginning of systole and diastole
      1. S1 Heart Sound
      2. S2 Heart Sound
  2. Timing
    1. Determine timing of murmur
      1. Systolic Murmur
      2. Diastolic Murmur
    2. Determine Early, Middle or late in interval
  3. Severity
    1. Grade 1/6: Barely audible
    2. Grade 2/6: Just easily audible
    3. Grade 3/6:
    4. Grade 4/6:
    5. Grade 5/6: Loudest requiring a stethoscope
    6. Grade 6/6: Heard with stethoscope off chest
  4. Location
    1. Identify valve area involved
  5. Pattern
    1. Uniform: Constant
    2. Crescendo: Increasing
    3. Decrescendo (Diminuendo): Decreasing
    4. Crescendo-Decrescendo: Diamond Shaped Murmur
  6. Pitch
    1. Low pitched
      1. Best heard with bell chest-piece at light pressure
    2. High pitched
      1. Best heard with diaphragm at firm pressure
      2. Valve insufficiency murmurs are high pitched due to higher velocity Blood Flow
  7. Dynamic Maneuvers
    1. Position
      1. Supine
      2. Erect
      3. Left lateral decubitus position
    2. Exercise
  • Interpretation
  1. Benign murmur findings
    1. Murmur characteristics
      1. Crescendo-decrescend character
      2. Musical or vibratory murmur
      3. Quiet murmur (Grade 2 or less)
      4. Timing: Early systolic or mid Systolic Murmur
      5. Location: Left sternal border or pulmonic area
    2. Associated findings absent
      1. Cardiopulmonary symptoms absent
      2. Family History absent
      3. Exam (BP, pulse, auscultation) otherwise normal
      4. Normal physiologic split S2 without gallup or click
  2. Pathologic murmur findings
    1. Murmur characteristics
      1. Timing: Diastolic, mid-late systolic, holosystolic
      2. Loud murmur (Grade 3 or greater)
      3. Murmur exacerbated by Valsalva Maneuver
      4. Murmur radiates to Carotid Artery or axilla
    2. Associated findings present
      1. Arrhythmia present
      2. Symptoms: Chest Pain, Palpitation, Dyspnea, Syncope
      3. Sudden Cardiac DeathFamily History
      4. Jugular Venous Pulsation abnormal
      5. Arterial pulsation abnormal
        1. Wide Pulse Pressure
        2. Water-Hammer Pulse (rapidly rising, bounding)
        3. Weak, slow rising pulse
      6. Other abnormal precordial exam
        1. Other heart sounds (e.g. Loud S1, fixed split S2)
        2. Left ventricular heave
  • Resources
  1. University of Michigan Heart Sound and Murmur Library
    1. http://www.med.umich.edu/lrc/psb/heartsounds/