ASD During inspiration there is increased venous return

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Heart Murmurs A LearnTheHeart.com Slideshow
Presentation
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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.
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How to listen to the heart
A aortic listening post P pulmonic listening
post T tricuspid listening post M mitral
listening post E Erbs point
E
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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.

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Murmurs

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

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Murmurs

• Describing murmurs - Timing
• Murmurs may occur in systole, diastole, or may be
  continuous.

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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?

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Murmurs

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

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Murmurs

• Describing murmurs Intensity
• Diastolic murmur intensity is graded out of 4, a
  mistake made by many people (they often use the
  systolic scale).

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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.

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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!

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Murmurs - Location
Describing murmurs - Location

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

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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.

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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.

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Murmurs Dynamic auscultation
TAO transient arterial occlusion afib
atrial fibrillation PVC premature
ventricular contraction
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List of Murmurs
Basic murmurs
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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).

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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!

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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.

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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.

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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.

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The murmur of pulmonic stenosis

• Basic murmurs pulmonic stenosis (PS)
• Pulmonic stenosis is much less common than aortic
  stenosis (except in pediatrics).

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The murmurs of AS and PS
Note AS is much more common than PS!
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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.

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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.

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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 (Carvallos sign).

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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 Erbs point.

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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.

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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!

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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.

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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.

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The murmur of a PDA
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The murmur of a PDA

• Basic murmurs PDA
• This continuous murmur is often referred to as a
  machinery murmur or Gibsons murmur.
• The murmur peaks at the S2 heart sound (which is
  often heard to hear) and is creshendo-decreshendo
  in shape.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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The murmur of HOCM
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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.

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The murmur of HOCM
Basic murmurs Comparing AS and HOCM
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Summary Systolic murmurs
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Summary Diastolic murmurs
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Dynamic auscultation