Transcript Heart Sounds Detecting and Analyzing Heart Murmurs

Murmurs:
Do you hear what I hear?
When does it matter?
Nikhil K Chanani MD
Audience Poll
 You are examining a 5 day old and find either:
• A) a 2/6 systolic murmur in an otherwise
asymptomatic child
• B) a saturation of 89% in an otherwise
asymptomatic child with no murmurs
• C) poor pulses and mottled skin in a
distressed infant with no murmurs
 Which is least likely to have hemodynamically
significant cardiac disease?
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Background
 Up to 2/3 of children will have a murmur
heard at some point in their childhood
 Incidence of congenital heart disease is
8/1000
• This means less than 2% of all murmurs
are associated with congenital heart
disease
 As many as 80% of heart lesions are missed
during initial neonatal exam*
* Emslie et al, Examination for cardiac malformations at six weeks of age. Arch. Dis.
Child Fetal Neonatal ed. 1999; 80: F46.
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
A cardiac murmur is the sound of turbulent
blood flow. A murmur does not necessarily
indicate heart disease.
 The clinician should emphasize this fact to the
patient’s family.
 A murmur is merely one part of a complete
cardiovascular assessment.
• History, vital signs, physical diagnosis,
diagnostic testing
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Auscultation
 S1: closing of mitral & tricuspid valves
• Normally single
• heard best at apex or LLSB
• Split S1 uncommon
 Conduction delay: RBBB, LBBB
 Valvular problem, ex: Ebstein’s
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Auscultation
 S2: closing of aortic & pulmonary valves
• Physiologic splitting, varies with
respiration
• Heard best at LUSB
• Physiologic demo
 Abnormal S2
• Widely split
• Narrowly split
• Single S2
• Paradoxically split
• Abnormal intensity
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Auscultation
 S3: rapid ventricular filling
• Occurs soon after S2
• Best heard at the apex or LLSB
• May be normal in older children (not
infants!)
• Dilated ventricles
 large shunts
 dilated cardiomyopathy
 myocarditis
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Auscultation
 S4: increased atrial pressure against
stiff ventricle
• Best heard at the apex
• Never normal in children
• Immediately prior to S1
• Indicates poor ventricular
compliance
 HTN,
 decreased ventricular
compliance
 HCM
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Auscultation
 Clicks
• Ejection click
 Sounds like split S1, but heard at base
 Dysplastic semilunar valve, dilated
great artery
• Midsystolic click
 Heard at apex in MVP
 Opening snap
• Early diastolic, at
apex in mitral stenosis
 Friction Rub
• Pericarditis, effusion
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Physical exam - Murmurs
 Sound created by turbulant
bloodflow through heart and
great vessels
 Murmurs
• grade/intensity
• Timing
• Location
• Radiation
• Shape
• Quality
• frequency/pitch
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Murmurs
 Systolic Murmurs
• Ejection
 interval b/w S1 & murmur
 crescendo-decrescendo
 innocent or pathologic
• Regurgitant/holosystolic
 begins with S1
 always pathologic
– VSD, TR, MR
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Murmurs
 Diastolic Murmurs: between S2 & S1
• Early: decrescendo
 AI and PI
• Mid/Late: low pitched, may start with S3
 AV valve stenosis or increased flow
 Continuous Murmurs: continue through S2
• AP or AV connections: PDA, AVM, shunts
• Combination systolic and diastolic
 To-fro murmurs: AS and AI, PS and PI
• Venous hum
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Grading Murmurs
Without thrill
Grade 1: very faint, barely audible
Grade 2: soft but easily heard
Grade 3: intermediate
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Grading Murmurs (cont.)
With thrill
Grade 4: loud, with a palpable vibration
(thrill)
Grade 5: very loud, audible with edge of
stethoscope on chest
Grade 6: very loud, audible with
stethoscope just off chest
Diastolic murmurs are graded from 1-4
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Systolic Murmurs
A systolic murmur generally represents
forward flow through the aortic or
pulmonary valve
backward flow through the mitral or
tricuspid valve
flow through the VSD
innocent (Still’s) murmur through the LV
cavity
innocent flow murmurs through aortic and
pulmonary valves with anemia, bradycardia,
fever or hyperthyroidism
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Diastolic Murmurs
A diastolic murmur generally represents
forward flow through the mitral or tricuspid
valve
backward flow through the aortic or
pulmonary valve
innocent flow murmurs across mitral or
tricuspid valve with anemia, bradycardia,
fever, or hyperthyroidism
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Continuous Murmurs
Venous hums
Patent ductus arteriosus
Collateral vessels
Coronary arterial fistulae or any arteriovenous
fistula
Surgical systemic arterial to pulmonary arterial
shunts
Aorticopulmonary windows
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Innocent Murmurs
The following is a list of innocent murmurs and
their characteristics in children and
adolescents:
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Innocent Murmurs (cont.)
Still’s murmur
Most common, vibratory, musical in nature;
LLSB-apex; louder supine; murmur
decreases with Valsalva strain; R/O VSD,
MR, sub-AS
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Innocent Murmurs (cont.)
Supraclavicular arterial bruit
Above clavicles; murmur is low intensity and
in early systole; possible associated thrill;
R/O AS, PS, VSD, coarctation
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Innocent Murmurs (cont.)
Venous hum
Continuous; gravity-dependent; due to
turbulent subclavian, innominate vein and
SVC flow; murmur disappears when patient
supine; R/O anemia, hyperthyroidism,
cerebral AVM
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Innocent Murmurs (cont.)
Peripheral pulmonary stenosis (newborn)
Base, axillae, back bilaterally; relative PA
hypoplasia and bracing; murmur persists
until three to six months; R/O ASD, PDA,
TOF
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Innocent Murmurs (cont.)
Physiologic pulmonary ejection murmur
Slightly harsh; second-third LICS; louder
supine; no click; R/O ASD, valvular PS
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Pathologic Murmurs
For any of the following pathologic murmurs,
referral to a pediatric cardiologist is indicated:
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Pathologic Murmurs (cont.)
Loud systolic murmur (> grade 4) outflow tract
obstruction; AV valve insufficiency; VSD
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Pathologic Murmurs (cont.)
Mid to late systolic murmur: MVP or TVP with
insufficiency
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Pathologic Murmurs (cont.)
Pansystolic murmur: VSD, MR, TR
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Pathologic Murmurs (cont.)
Continuous murmur other than venous hum:
blowing, crescendo-decrescendo (PDA,
collateral, shunt)
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Pathologic Murmurs (cont.)
Diastolic murmur: semilunar valve
insufficiency;
AV valve stenosis
(fixed vs. relative)
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Pathologic Murmurs (cont.)
Associated CV abnormalities; pulses,
perfusion; precordial impulse; heart sounds
(S1-S4); clicks, blood pressure; symptoms; lab
studies
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Pathologic Murmurs (cont.)
Loud murmur in delivery room/nursery: outflow
tract stenosis; AV valve insufficiency
Every baby has a large PDA after delivery.
This should not, however, cause an audible
murmur.
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Summary
“Listen in all areas for heart murmurs.
First in systole and then in diastole.
Concentrate on dissection.
After much practice, this should become
automatic.”
From “Listening to Heart Murmurs in Infants and Children”
by Jerome Liebman, MD
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