Heart Murmurs - Exercise Pharmacology

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					Heart Murmurs

 A LearnTheHeart.com
Slideshow Presentation
   What are heart murmurs?
A heart murmur is an audible sound within the heart due
to turbulent blood flow across a valve. Murmurs can occur
in systole or diastole. If a murmur-like sound occurs
outside of the heart (peripherally), it is called a “bruit”. In
general, murmurs occur due to valve stenosis, valve
regurgitation, or congenital cardiac defects.
How to listen to the heart

               A = aortic listening post
               P = pulmonic listening post
           E
               T = tricuspid listening post
               M = mitral listening post
               E = “Erb’s point”
      The stethoscope basics

The stethoscope
•   Every stethoscope has a “bell” and a “diaphragm”.
•   The bell is used to hear low pitched sounds and the
    diaphragm is used to hear high pitched sounds.
                          Murmurs

How to describe a murmur?
•   Timing
•   Intensity
•   Shape
•   Pitch
•   Location
•   Radiation
•   Dynamic Auscultation (changes with maneuvers)
                             Murmurs

 Describing murmurs - Timing
 •   Murmurs may occur in systole, diastole, or may be continuous.
      Systolic murmurs                    Diastolic murmurs
• Aortic stenosis (AS)              • Aortic regurgitation (AR)
• Pulmonic stenosis (PS)            • Pulmonic regurgitation (PR)
• Mitral regurgitation (MR)         • Mitral stenosis (MS)
• Tricuspid regurgitation (TR)      • Tricuspid stenosis (TS)
• Mitral valve prolapse (MVP)             Continuous murmurs
• Atrial septal defect (ASD)        • Patent ductus arteriosus
• Ventricular septal defect (VSD)   • Combination murmurs
                        Murmurs

Describing murmurs - Timing
•   Systolic murmurs occur between S1 and S2
•   Diastolic murmurs occur between S2 and S1
•   Remember can you tell S1 and S2 apart?
                                Murmurs

  Describing murmurs – Intensity
  •   Systolic murmur intensity is graded on a scale of 6.

                      Systolic murmur grading
Grade I/VI            • Barely audible
Grade II/VI           • Audible, but soft
Grade III/VI          • Easily audible
Grade IV/VI           • Easily audible and associated with a thrill
Grade V/VI            • Easily audible with a thrill and heard with the
                      stethoscope lightly on the chest
Grade VI/VI           • Easily audible with a thrill and heard with the
                      stethoscope off of the chest
                          Murmurs

 Describing murmurs – Intensity
 •   Diastolic murmur intensity is graded out of 4, a mistake
     made by many people (they often use the systolic scale).
                 Diastolic murmur grading
Grade I/IV        • Barely audible
Grade II/IV       • Audible, but soft
Grade III/IV      • Easily audible
Grade IV/IV       • Loud
                             Murmurs

Describing murmurs - Shape
•   Murmurs can be described as creshendo, decreshendo, creshendo-
    decreshendo, or uniform (holosystolic).
•   Murmurs are also classified as either a systolic ejection murmurs
    (SEM) or holosystolic. SEMs include creshendo and creshendo-
    decreshendo murmurs. A SEM does not overwhelm the S1 and S2
    heart sounds while a holosystolic murmur does.
                            Murmurs

Describing murmurs - Pitch
•   Murmurs are classified as either high or low pitched.
•   High pitched murmurs result when there is a large difference in
    pressures on either side of the anomaly causing the murmur.
•   For example, the murmur of AS is high pitched since pressure
    gradients between the LV and aorta are large in this setting. On
    the other hand, the murmur of MS is low pitched since pressure
    gradients between the LA and LV are relatively small.
•   Remember, high pitched sounds are heard with the diaphragm
    and low pitched sounds are heard with the bell!
           Murmurs - Location

Describing murmurs - Location
                     • The location that the murmur is
                     best heard is crucial to
                 E   determining its etiology.
                     • Aortic murmurs are heard at
                     the aortic listening post,
                     pulmonic murmurs are heard
                     best at the pulmonic listening
                     post etc…
                            Murmurs

Describing murmurs - Radiation
•   Certain murmurs radiate to listening posts and other areas far
    away from which the murmur originates.
•   For example, on occasion, the murmur of AS can radiate to the
    apex, although the aortic listening post is at the base. Also, the
    murmur of AS radiates to the carotid arteries and is sometimes
    mistaken for a carotid bruit.
•   Other murmurs, such as mitral regurgitation, radiate to the
    axillary region.
      Murmurs – Dynamic auscultation

Describing murmurs – Dynamic auscultation
•   Many physical maneuvers exists to alter the hemodynamics
    within the heart and circulation.
•   These maneuvers have specific effects on specific murmurs and
    are frequently used to help determine the etiology of the
    murmur.
•   Some non-physical maneuvers are also sometimes used. These
    include inhaling amyl nitrate or simply listening to the effect that
    a PVC (premature ventricular contraction) has on a murmur.
                Murmurs – Dynamic auscultation
 Maneuver                            Effect of maneuver
 Valsalva__________                  • Multiple effects, but most importantly a decrease in
 _                                   venous return to RV and LV, decreased afterload.
 Respiration                         • Inspiration increases venous return to RV and
 ________                            decreases LV filling, expiration does opposite
 Squat/Leg raise                     • Increases afterload and venous return to RV and LV
 Standing                            • Decreases venous return to RV and LV
 Post PVC/afib                       • Post PVC pause or pauses in afib result in increased
 ______                              LV filling due to increased time of diastole.
 Handgrip/TAO                        • Increases afterload
 Amyl nitrite                        • Reduces afterload (arterial vasodilator)
TAO = transient arterial occlusion   afib = atrial fibrillation   PVC = premature ventricular contraction
                             List of Murmurs

     Basic murmurs
Systolic                             Diastolic
Systolic ejection murmurs            Early diastolic murmurs
  - Aortic stenosis                    - Aortic regurgitation
  - Pulmonic stenosis                  - Pulmonic regurgitation
  - HOCM                             Mid/late diastolic murmur
Pansystolic murmurs                    - Mitral stenosis
  - Mitral/tricuspid regurgitation     - Tricuspid stenosis
  - Ventricular septal defect        Other murmurs
Late systolic murmur                   - ASD, VSD, PDA, other rare murmurs
  - Mitral valve prolapse
        The murmur of aortic stenosis

Basic murmurs – aortic stenosis (AS)
•   The murmur of AS is a systolic, creshendo-decreshendo,
    high pitched murmur located at the aortic listening post
    (right upper sternal border or RUSB), and it radiates to the
    carotid arteries.
•   Depending on the severity of AS, the murmur may change.
    As AS worsens, the murmur peaks later in systole.
•   Also, in severe AS, the closing of the aortic valve is
    delayed, often resulting in a paradoxical split S2 heart
    sound (if the S2 is audible).
        The murmur of aortic stenosis

Basic murmurs – aortic stenosis (AS)
•   When AS worsens, the intensity of the A2 (and thus S2) heart sound
    decreases. In severe AS, the S2 heart sound is almost absent!
        The murmur of aortic stenosis

Basic murmurs – aortic stenosis (AS)
•   Note: The murmur of AS often also radiates to the apex of
    the heart (the mitral listening post) where it may actually
    sound holosystolic!
•   As you can imagine, this makes it difficult to tell if there is
    coexistent AS and MR, or simply radiation of the AS to the
    apex. Dynamic auscultation is used to determine which
    valvular lesion is present (see later section).
•   This phenomenon of AS radiating to the apex confusing
    the examiner is called the “Gallavaradin effect”.
     The murmur of pulmonic stenosis

Basic murmurs – pulmonic stenosis (PS)
•   The murmur of PS is similar to that of AS, however since
    the A2 usually comes before P2, the murmur of PS extends
    through the A2 sound making it difficult (mild PS) or
    impossible (severe PS) to hear.
•   The murmur of PS is best heard at the pulmonic listening
    post (left upper sternal border or LUSB) and does not
    radiate to the carotids.
•   The PS murmur may, however, radiate to the left shoulder
    and supraclavicular region.
     The murmur of pulmonic stenosis

Basic murmurs – pulmonic stenosis (PS)
•   As a general rule, all right sided heart murmurs will
    increase in intensity with inspiration due to the increase in
    venous return, although this change is most pronounced in
    tricuspid regurgitation (TR) and minimal in PS.
•   As PS worsens, the time that it takes for RV ejection
    increases, thus delaying the closure of the pulmonic valve.
    This results in a delayed P2 and thus a widened split S2.
•   As PS worsens, the mobility of the pulmonic valve leaflets
    decreases. This diminishes the intensity of the P2 sound.
     The murmur of pulmonic stenosis

Basic murmurs – pulmonic stenosis (PS)
•   Pulmonic stenosis is much less common than aortic
    stenosis (except in pediatrics).
The murmurs of AS and PS




       Note: AS is much more common than PS!
     The murmur of mitral regurgitation

Basic murmurs – mitral regurgitation (MR)
•   The murmur of MR is a holosystolic, uniform, high pitched
    murmur heard best at the mitral listening post (apex)
    radiating to the axilla.
•   The intensity of the murmur does not change with
    respiration (helps to distinguish from TR).
•   Since the intensity of the murmur is loud immediately after
    the onset of S1 and extends to just before the S2, often
    the S1 and S2 sounds is overwhelmed by the murmur and
    are completely inaudible.
     The murmur of mitral regurgitation

Basic murmurs – mitral regurgitation (MR)
•   Remember there are three different holosystolic murmurs
    which may be difficult to distinguish: MR, TR, and VSD.
        The murmur of tricuspid regurgitation

Basic murmurs – tricuspid regurgitation (TR)
•   The murmur of TR is holosystolic in indistinguishable from
    the murmur of MR, except TR radiates to the right lower
    sternal border (not the left axilla), and the murmur of TR
    increases with inspiration (Carvallo’s sign).
                The murmur of a VSD

Basic murmurs – VSD
•   A ventricular septal defect (VSD) is a congenital hole in the
    part of the heart that separates the LV from the RV.
•   Blood abnormally flows from the LV (high pressure) to the RV
    (low pressure) creating turbulent blood flow and a holosystolic
    murmur heard best at “Erb’s point”.
               The murmur of a ASD

Basic murmurs – ASD
•   An atrial septal defect (ASD) is a congenital hole in the
    part of the heart that separates the LA from the RA.
•   Blood abnormally flows from the LA (high pressure) to the
    RA (low pressure) creating turbulent flow and a typical
    “flow murmur” across the pulmonic valve.
•   The murmur is a systolic ejection murmur (SEM) located at
    the pulmonic listening post without radiation.
•   Remember that an ASD is almost always associated with a
    fixed split S2.
               The murmur of a ASD

Basic murmurs – ASD
•   During inspiration there is increased venous return to the
    right side of the heart leading to increased pulmonic valve
    flow and thus delay in the closure of pulmonic valve (P2).
•   During expiration there is less venous return to the right
    heart decreasing right sided pressures thus allowing more
    blood to flow through the ASD resulting in increased flow
    through the pulmonic valve and again a delayed P2.
•   So the P2 is always delayed resulting in a fixed split S2!
              The murmur of a ASD

Basic murmurs – ASD
•   Note the fixed split S2 and note that the murmur extends
    through to the P2 heart sound.
               The murmur of a PDA

Basic murmurs – PDA
•   A patent ductus arteriosus (PDA) refers to a persistent
    communication between the pulmonary artery and the
    aorta which normally closes shortly after birth.
•   Since the aortic pressure always exceeds the pulmonic
    artery (PA) pressure, blood is always moving from the
    aorta to the pulmonary artery (during both systole and
    diastole) creating turbulent blood flow and thus a
    continuous murmur.
The murmur of a PDA
               The murmur of a PDA

Basic murmurs – PDA
•   This continuous murmur is often referred to as a
    “machinery murmur” or Gibson’s murmur.
•   The murmur peaks at the S2 heart sound (which is often
    heard to hear) and is creshendo-decreshendo in shape.
    The murmur of mitral valve prolapse

Basic murmurs – mitral valve prolapse (MVP)
•   The murmur of MVP does not start until mid-systole and
    occurs due to mitral valve regurgitation after the abnormal
    valve prolapses into the LA.
•   The sudden tensing of the valve and the chordae
    tendineae causes a “click” to occur just before the murmur.
     The murmur of mitral valve prolapse

Basic murmurs – mitral valve prolapse (MVP)
•   The timing of the click heard in MVP can be altered using
    dynamic auscultative maneuvers.
•   Sudden standing from a squatting position will decrease venous
    return to the heart and thus decrease LV volume. This moves
    the click earlier in systole.
•   Sudden squatting from a standing position will increase venous
    return to the heart and thus increase LV volume. This moves the
    click later in systole.
     The murmur of mitral valve prolapse

Basic murmurs – mitral valve prolapse (MVP)
•   Extreme increases in LV volume can actually eliminate the click
    and the murmur of MVP. Conversely, extreme decreases in LV
    volume can cause MVP to sound holosystolic! So these
    maneuvers can be helpful to distinguish MVP from pure MR.
    The murmur of aortic regurgitation

Basic murmurs – aortic regurgitation (AR)
•   The murmur of AR is a high pitched, early diastolic
    murmur usually heard best NOT at the aortic listening
    post, but at the left lower sternal border.
•   If the AR is due to aortic root disease (see valvular heart
    disease section), then the murmur may be heart at the
    aortic listening post.
•   This murmur is heard best at end-expiration with the
    patient sitting up and leaning forward.
    The murmur of aortic regurgitation

Basic murmurs – aortic regurgitation (AR)
•   AR is often associated with a separate murmur termed the
    “Austin-Flint murmur”. This occurs when the regurgitent jet
    from the aortic valve strikes the anterior leaflet of the
    mitral valve causing it to vibrate.
•   Often, a systolic flow murmur is also heard since there is a
    large amount of forward flow through the aortic valve in
    the setting of severe AR.
    The murmur of aortic regurgitation

Basic murmurs – aortic regurgitation (AR)
•   As the AR worsens, it takes less time for the aortic
    pressure and the LV pressure to equalize, thus the murmur
    shortens.
     The murmur of pulmonary regurgitation

Basic murmurs – pulmonary regurgitation (PR)
•   The murmur of PR is exactly the same as the murmur of
    AR, except it is heard best at the pulmonic listening post
    and the intensity may increase with inspiration. This
    murmur is called the “Graham-Steell murmur”.
        The murmur of mitral stenosis

Basic murmurs – mitral stenosis (MS)
•   The murmur of MS is a low pitched, uniquely shaped
    diastolic murmur heard best at the mitral listening post
    and often times associated with an “opening snap”.
                The murmur of HOCM

Basic murmurs – HOCM
•   The murmur of Hypertrophic Obstructive Cardiomyopathy
    (a.k.a. IHSS) is similar to that of AS.
•   It is a high-pitched creshendo-decreshendo systolic ejection
    murmur heard best at the left lower sternal border.
•   The murmur of HOCM does not radiate to the carotid arteries,
    unlike AS.
•   The S2 heart sound is clearly audible, unlike severe AS.
•   Like AS, paradoxical splitting of the S2 heart sound may be
    present.
The murmur of HOCM
                The murmur of HOCM

Basic murmurs – HOCM
•   Maneuvers are crucial to distinguish HOCM from AS. Any
    maneuver that decreases LV volume will worsen the obstruction
    thus increasing the murmur. The opposite is also true.
•   The Valsalva maneuver decreases LV volume which increases
    the murmur of HOCM while decreasing that of AS. Standing
    from a squatting position would do the same.
•   Squatting from a standing position increases LV volume thus
    relieving the obstruction and decreasing the murmur of HOCM,
    however the murmur of AS increases since more blood must be
    forced through the stenotic aortic valve.
         The murmur of HOCM

Basic murmurs – Comparing AS and HOCM
Summary – Systolic murmurs
Summary – Diastolic murmurs
                Dynamic auscultation
                MR/VSD   AS   HOCM   MVP   TR/PR
Valsalva                                
Inspiration        -     -     -      -     
Squat              -                      -
Standing           -     -                 -
Post PVC/afib      -                -      -
Handgrip                -                 -
Amyl nitrite                 -      -      -

				
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