Cardiac Murmurs in the Newborn Infant Carrie Phillipi MD, PhD

Cardiac Murmurs in the
Newborn Infant
Carrie Phillipi MD, PhD
Prevalence of Congenital Heart
Disease (CHD)
• <1 per 100 live births
Most cardiac murmurs are benign!
Risk Factors for CHD
(when is CHD more likely)
• Family history of CHD
• Increased maternal age: increased risk for
chromosomal abnormalities
• Genetic syndromes (Down syndrome, Turner’s)
• Finding of other major anomalies (VATER, cleft
palate, neural tube, etc.)
• Plurality (multiple gestation)
Maternal Risk Factors for CHD
• Maternal Diabetes: 3-5% risk of CHD
– VSD, conotruncal defects, d-TGA
– Risk reduced with good diabetic control
– Importance of supplemental vitamins
• Maternal systemic lupus
– Complete heart block
– Transplancental passage of maternal antiSS-A or anti-SS-B autoantibodies
Genetic Risk for CHD
• Chromosome Disorders
– Trisomy 21 (Down Syndrome)
• ~50% have CHD
– Trisomy 18 and 13
• >90% have CHD
• VSD, DORV, PDA, conotruncal defects
Genetic Risk for CHD
• Chromosome Disorders
– 45X deletion syndrome (Turner syndrome):
35% have CHD: coarctation, bicuspid aortic
valve, potential for developing aneurysm of
– 22q11 deletion (DiGeorge syndrome; Velocardio-facial syndrome, CATCH-22)
• Truncus, Tetralogy, Interrupted Aortic Arch
• Need to screen parents.
Neonatal Manifestations of
Congenital Heart Disease
• Heart Murmur (~ 50%)
• Cyanosis and/or Arterial Desaturation using
pulse oximetry
• Pallor or Poor Perfusion
• Tachypnea
• Tachycardia
• Slow growth (FTT)
Heart Murmurs
• ~50% of newborns with significant CHD have
minimal or no murmur at birth (large VSD, single
ventricle, transposition, TAPVR)
• Left to right shunt defects such as large VSD do
not develop murmurs until the PVR drops (days to
Cardiac murmur is an insensitive marker for CHD
Grading Heart Murmurs
1 Softer than Heart Sounds
2 Equal to Heart Sounds
Louder than Heart Sounds
The Cardiac Exam
• Observation
• Palpation (precordium, pulses, perfusion,
• Auscultation
Listening is just one step. Be as descriptive as
Heart Murmurs
Remember most cardiac murmurs are benign,
• Factors that increase likelihood of CHD
– Persistence
– Intensity
– Association with any symptoms
Unexplained Tachypnea
• Persistent resting tachypnea (greater than
60/minute) and no murmur
• Need to rule out cardiac etiology
• ~10% of CHD presents with this finding
• Importance of chest X-ray and Pulse Oximetry
Screening tests
• Pulse oximetry
• Chest X-ray
• 4 extremity blood
• EKG: best used when
concern is cardiac rhythm
Infant with Cardiomegaly
Cyanotic vs. Acyanotic CHD
• Pulse Oximetry!
• The cyanotic infant needs immediate
Cyanotic Infant
Oxygen challenge
Lung vs. Heart???
Oxygen supplementation will not correct
pulse oximetry to 100% with cyanotic
congenital heart disease.
Transient Ductus Murmur of
the Healthy Newborn
• Soft systolic murmur, grade 1-2 in intensity, often
higher pitched
• Caused by flow in closing ductus. Typically heard
best at 4-16 hours of life
• Studies indicate that it can be heard in most
newborn infants
• Hallmark of this murmur is its transient nature
• Infants are asymptomatic (normal feeding;
breathing comfortably)
• The Auscultation Assistant - Systolic Murmurs
Delayed closure of PDA in
Premature Infants
• Risk factors include lower gestational age
and finding of RDS
• Should be suspected in any preemie with
respiratory symptoms and new onset murmur
• Larger PDA’s in the sickest preemie infants
are often silent
• CXR: ground-glass or “wet” appearance
Physiologic Peripheral
Pulmonary Stenosis (PPS)
• Murmur of PPS is high pitched
• Heard well in both axillae and into posterior
lung fields
• More common in infants born prematurely
• Infants are asymptomatic
• Resolves by 3-6 months
• CXR, EKG, & Pulse oximetry: normal
Innocent (Still’s) Murmur
• Lower pitched
• Soft, grade 1-2 in intensity
• Described as “musical”, “vibratory”, “twanging”or
“barking seal”
• Often heard best at cardiac apex
• CXR and pulse oximetry normal
• The Auscultation Assistant - Systolic Murmurs
Infant Heart Murmurs
• Asymptomatic Infant with persistent murmur
(feeding well, normal pulse oximetry and
CXR): needs close follow-up, echo/cardiac
referral when appropriate
• Infant with murmur and any other clinical
sign: (tachypnea, decreased pulses,
abnormal CXR, arterial desaturation): needs
evaluation ASAP!
CHD with Left to Right Shunts
(common cause of early cardiac murmurs)
AVSD (AV canal defect)
50% of children with CHD will
have one of these defects!
Ventriculoseptal Defect (VSD)
• Most Common Cardiac Defect (35% of all
cardiac defects)
• 50% male:female
• Small defects are detected earlier (1st days of
life) than larger defects
• Murmur is due to systolic pressure difference
between LV and RV
• The Auscultation Assistant - Systolic Murmurs
VSD: Natural History
• ~ 50%: close spontaneously
• ~ 25%: persistent small shunts that do not
require surgery (risk for SBE)
• ~ 25%: require surgical closure
• Soft systolic murmur, grade 1-2 intensity,
heard in pulmonary listening area (can mimic
the murmur of PPS)
• Typically not heard for several weeks
• Most infants with ASD are asymptomatic
• Mild cardiomegaly on CXR
• Normal Pulse Oximetry
• The Auscultation Assistant - Systolic
ASD: Clinical Findings and
Natural History
• 65% female prevalence
• Murmur frequently sounds benign and is
often overlooked!
• Murmur: due to increased flow across
pulmonary valve
• Spontaneous closure occurs in those
diagnosed in 1st month of life
• PFO (defects < 3 mm) is common and benign
• No risk for SBE
AV Septal Defect
• Also called AV Canal defect or Endocardial
Cushion defect
• ASD, VSD, and commonly AV regurgitation
• Large VSD allows systemic pressure
transmission into pulmonary vascular bed
• Associated with high PVR and systemic RV
pressure (and hence, absent or soft murmur)
Coarctation: Clinical Findings
• Systolic murmur, grade 2 intensity, at left midclavicular area to mid-scapular area
• Diminished lower extremity pulses
• Need for 4-extremity blood pressures
• Difficult diagnosis in the newborn prior to ductal
• 65% male prevalence
• Think possible Turners syndrome in girls with
Critical Coarctation (or IAA)
• All pulses diminished with cool mottled
extremities, delayed capillary refill, pallor,
poor perfusion, acidosis, low cardiac output
• Cardiac murmur often minimal; listen for
• Need for PGE infusion
• Need for cardiac operation
Heart Sounds & Murmurs
• The Auscultation Assistant - Systolic