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A. Basic Heart Soundsnavigator

  1. S1 (lub): precedes systole. Mitral and tricuspid valves close. Ventricles contract
  2. S2 (dub): precedes diastole. Aortic and pulmonic valves close (A2 then P2). Atria contract
  3. S3 Gallop (lub-dub-sh): early diastole (see below)
  4. S4 Gallop (bu-lub-dub): atrial contraction to non-compliant (stiff, thick) ventricle
  5. Murmurs - usually due to rapid flow (often normal) or to valvular down (abnormal)
  6. Rubs - pericardial inflammation causes rubbing against adjacent structures (abnormal)
  7. Clicks - common, may correlate with mitral valve prolapse (midsystolic click)

B. Schematic of Heart Soundsnavigator

BuLubDubSshBuLub
(S4) -- S1---systole---S2 -- (S3)--diastole--(S4) -- S1

C. Heart Murmurs [1]navigator
  1. Introduction
    [Figure] "Cardiac Cycle"
    1. Indicate valve problems in some cases
    2. Many cases of systolic ejection murmurs (SEM) are normal
    3. Flow murmurs are best heard with diaphragm of stethoscope, usually at apex
    4. Cardiologists are able to detect systolic murmurs correctly about 45% of the time [1]
  2. Types of Murmurs
    1. Diastolic
    2. Systolic
    3. Holosystolic: Regurgitation Murmur (in most cases)
    4. Crescendo-Decrescendo: Stenosis Murmur (in most cases)
    5. Flow Murmur (normal finding or high output condition)
  3. Location on Chest of Valve Sounds
    1. Aortic outflow tract: central/right upper region of chest (T2)
    2. Tricuspid sounds: center lower region of chest (T3/4)
    3. Pulmonic outflow tract: left upper region of chest (T2)
    4. Mitral valve: at apex or heart (T5)
    5. Normal point of maximal impact: Midclavicular line T5; palpate apex, LV

D. Causes of Murmursnavigator

  1. Valve Stenosis
    1. Valve is hardened; decreased flow across
    2. Therefore, valve fails to open completely
    3. Result is that downstream pump must hypertrophy to pump across higher gradient
  2. Valve Regurgitation (Insufficiency)
    1. Valve fails to close completely
    2. Result is that upstream pump will dilate, possibly hypertrophy
    3. Downstream pump will dilate without hypertrophy
    4. Holosystolic murmurs (not systolic ejection murmurs)
  3. Normal Variant
    1. Usually in young persons
    2. "Flow Murmur" usually without radiation, no other cardiac abnormalities
    3. Loud murmurs (>II/VI systolic, >II/IV diastolic) should generally be evaluated further

E. Specific Valvular Abnormalities and Their Murmurs [1]navigator

  1. Aortic Insufficiency
    1. Diastolic murmur
    2. Right Upper Sternal Border (RUSB)
  2. Aortic Stenosis [1]
    1. Systolic murmur, RUSB radiating to Carotids
    2. Significant stenosis is accompanied by delayed rise in carotid pulse
    3. Decreased intensity of S2 is also found
  3. Mitral Regurgitation [1]
    1. Holosystolic murmur LLSB/Apex radiating to Left Axilla
    2. May be a late systolic murmur
  4. Mitral Stenosis
    1. S1 loud (closure of stenotic valve)
    2. Opening Snap follows A2
    3. Low pitched diastolic murmur ("rumble")
  5. Tricuspid Regurgitation
    1. Mid aortic outflow tract - lower left sternal border
    2. Increased murmur on inhalation
  6. Pulmonic Stenosis
    1. L sternal border, T2 area
    2. Holosystolic, radiates to back
  7. Bruits: sounds in arteries, usually due to stenosis (atherosclerosis in most cases)
  8. Split S2
    1. Normally occurs due on inspiration
    2. Normally, aortic valve closure (sound A2) precedes pulmonic (P2) closure on inspiration
    3. Inspiration causes delayed closing of pulmonic valve from increased filling of RV
    4. P2 sound is best heard over the pulmonic area (2nd left intercostal space)
    5. Pathological increase or fixed splitting may be due to failure of RV and LV to contract together
    6. Widened split S2 due to delayed closure of pulmonic valve, right bundle branch block, atrial septal defect, pulmonic stenosis, early closure of aortic valve, mitral regurgitation
    7. Often due to Right sided CHF or dilation; especially if dependent on respirations
    8. Paradoxical (P2 precedes A2) splitting in left bundle branch block, aortic stenosis, most pronounced on expiration

E. Eliciting Murmursnavigator

  1. Maneuvers
    1. Venous Return decrease: expiration, valsalva, standing
    2. Venous Return increase: inspiration, squatting, supine leg elevation
    3. Left Side down: Mitral Murmurs
    4. Sitting Up: Right Sided and Aortic Murmurs
    5. Afterload increase: hand clasping, straining
  2. Hypertrophic Cardiomyopathy
    1. Increases with valsalva maneuver (pressures in thorax increased obstruction)
    2. Decreases with squatting (improved flow through obstruction causes more normal sound)
    3. Increases with standing (lower LV filling with increased obstruction)
  3. Right Sided Murmurs
    1. Increases with Inspiration and Squatting
    2. Decrease with Expiration and Valsalva Maneuver

F. Summary of Causes of Valve Disease navigator

  1. Ischemic Heart Disease: failure of valve tissue (eg. chordae tendinea)
  2. Myocardial Infarction: rupture of tendons leads to acute valvular insufficiency
  3. Calcific Degeneration: mainly in older persons; common in rheumatic fever
  4. Infection: endocarditis. Mainly in IVDA - subacute bacterial endocarditis
  5. Trauma: rupture of chordae, papillary mm, most common
  6. Rheumatoid Disease: systemic lupus, systemic sclerosis, rheumatoid arthritis
  7. Rheumatic Fever: mitral > aortic stenosis
  8. Marfan Syndrome - aortic regurgitation most common

G. Gallops (Diastolic Heart Sounds) [4]navigator

  1. Called third (S3) and fourth (S4) heart sounds, usually refers to LV sounds
  2. Both S3 and S4 (LV) are best heard at apex of the heart with the bell (they are low pitch)
  3. With S3, heart sounds resemble "Ken--tuck-y"
    1. S3 is somewhat blowing
    2. Must distinguish from split S2 (A2-P2)
  4. With S4, heart sounds resemble "Ten-a--see"
  5. S3 is nearly always abnormal [2,4]
    1. Indicates severe hemodynamic alterations in most cases
    2. May be present and physiologic in younger persons, particularly <40 years of age
    3. Pathologically generated during rapid fill of LV, in dilated hearts
    4. Early diastolic filling leads to dilated LA with Dilated LV
    5. This is seen in heart failure, often accompanies pulmonary edema
    6. In most patients with an S3, the ejection fraction is <25%
    7. May be heard in patients with dilated cardiomyopathy who are not in pulmonary edema
    8. Associated with ~30% increased risk of poor outcomes in CHF [3]
    9. Should always be evaluated comprehensively
    10. About 50% sensitivity and ~90% specificity for detection of abnormal cardiac function when phonocardiographic detection is used; human detection likely reduces accuracy [4]
  6. S4 may be normal
    1. Often heard normally in children and young adults
    2. May be present in hypertrophic LV disease
    3. Signifies atrial contraction into non-compliant (usually hypertrophied) ventricle
    4. That is, indicates increased LV filling pressures (elevated LA pressure/LA hypertrophy)
    5. About 40% sensitivity and ~80% specificity for detection of abnormal cardiac function when phonocardiographic detection is used; human detection likely reduces accuracy [4]

References navigator

  1. Etchells E, Bell C, Robb K. 1997. JAMA. 277(7):564 abstract
  2. Tribouilloy CM, Enriquez-Sarano M, Mohty D, et al. 2001. Am J Med. 111(2):96 abstract
  3. Drazner MH, Rame JE, Stevenson LW, Dries DL. 2001. NEJM. 345(8):574 abstract
  4. Marcus GM, Gerber IL, McKeown BH, et al. 2005. JAMA. 293(18):2238 abstract