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Congenital Heart Disease
Seth Malin, MD
Bronson Methodist Hospital
MSU KCMS, College of Human Medicine
What is congenital heart disease?
Congenital heart defects are structural problems with
the heart present at birth. They result when a mishap
occurs during heart development soon after
conception and often before the mother is aware that
she is pregnant. Defects range in severity from simple
problems, such as "holes" between chambers of the
heart, or “extra” vessels, to very severe
malformations, such as complete absence of one or
more chambers or valves.
Many of these defects are simple conditions that are
easily fixed or need no treatment. A small number of
babies are born with complex congenital heart defects
that require special medical care soon after birth.
Over the past few decades, the diagnosis and treatment
of these complex defects has greatly improved. As a
result, almost all children who have complex heart
defects survive to adulthood and can live active,
productive lives.
National Heart Lung and Blood Institute, 2009
How serious is the problem?
Congenital heart defects are the most common birth defect and are the
number one cause of death from birth defects during the first year of
life. Nearly twice as many children die from congenital heart disease in
the United States each year as die from all forms of childhood cancers
combined. In 2005, 192,000 life-years were lost before age 55 in the
United States due to congenital heart disease. In 2004, hospital costs
totaled $2.6 billion.
American Heart Association, 2009
Where to start?
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Congenital heart disease occurs in from 2.5 to 8.8
babies per 1000 live born infants. The low incidence
is for severe disease only; the higher is for all
diagnoses including mild problems.
There is probably regional variation; some mild
disease is asymptomatic and is only diagnosed later
in life.
Severe disease almost always presents early.
Where to start?
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In a policy statement in 2009, the AAP and the AHA
estimated that the incidence of cyanotic congenital
heart disease in newborn infants to be 9 per 1000
live births.
The American Heart Association estimates that
about 35000 babies with CHD are born each year
Where to start?
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Michigan has a birth rate of about 125000 births per
year.
If the incidence of CHD is 9 per 1000, then about
1125 babies with heart disease will be born in
Michigan each year.
The NIH estimates that about 1000000 people are
living with congenital heart disease (2009).
How do we know?

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Prenatal ultrasound helps. Pediatric cardiologists can
perform fetal echocardiograms.
About 96 percent sensitivity for accurate diagnosis if
the physician and tech are skilled and experienced.
How do we know?

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Screening of “normal” newborn infants is somewhat
controversial.
We obviously can't perform an ECHO on all
newborns.
Use of postnatal pulse oximetry may be useful but is
still controversial (Pediatric Cardiology
2002;23:403-409). Only 4 infants were identified in
18 months using oximetry (sat <92) while 32 were
identified in 6 months using other means.
Let's talk about signs and symptoms
Symptom:
1. any phenomenon or circumstance accompanying something and
serving as evidence of it.
2.a sign or indication of something.
3.Pathology. a phenomenon that arises from and accompanies a particular
disease or disorder and serves as an indication of it.
Sign:
4.Medicine/Medical: the objective indications of a disease.
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
So most of my patients have signs but not symptoms
except as reported by the parents.
So....what are the signs that a patient may have a
congenital heart disease?
How do we know?

Most infants with cardiac disease have one of four
presentations:

Murmur

Cyanosis (with or without a murmur)

Progressive symptoms of heart failure

Catastrophic heart failure and shock
PedsReview 2007; 28(4):123-131
Murmur

Sound produced by turbulent blood flow through the
heart or valves

May be due to increased cardiac output in
conditions such as anemia

May be “innocent” and insignificant

May be due to abnormal valves (eg, aortic stenosis)

May be due to a hole (eg, VSD)

May be due to regurgitant flow (backflow through
a valve)
Murmurs
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Abnormal blood of low velocity or low volume may
not cause a murmur.
High-pitch or harsh murmurs, or those associated
with a thrill are pathologic.
A thrill is a palpable murmur; the thrill is caused by
highly turbulent blood flow directed towards the
chest wall.
Cyanosis
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From the Greek for BLUE
The term cyanide comes from the iron compound
(iron ferrocyanide) found in Prussian blue dye
Human poisoning causes the skin to become pink
due to cyanohemoglobin (according to wikipedia)
and causes death by blocking cytochrome oxidase
and blocking oxidative metabolism.
Cyanosis
Cyanosis is a blue color of the skin and mucous
membranes due the presence of deoxygenated
hemoglobin in the capillaries near the skin surface.
Deoxygenated Hemoglobin

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Deoxyhemoglobin is blue.
When the concentration of deoxyHb exceeds about
5mg/dl the blood and hence the tissues will have a
bluish cast.
Where the capillaries are near the skin, and not
obscured by hair or pigment, the skin and mucous
membranes will be bluish.
Cyanosis
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In the delivery room, babies are supposed to start
out blue and become pink. The first part to pink-up
is the head, and the easiest place to see the pink
color is in the lips and tongue.
Making babies pink too fast may not be good; the
NRP suggests using 40% oxygen for resuscitation to
avoid oxygen toxicity
Remember that Oxygen above RA is a drug!
Cyanosis
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Mixing of oxygenated and deoygenated blood
(arterial and venous) causes cyanosis in CHD.
Failure of oxygenated blood to get to the systemic
circulation will also cause cyanosis.
Cyanotic heart disease
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Remember the “Five Ts”
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Transposition
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Tetralogy of Fallot
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Tricuspid atresia

Total anomalous pulmonary venous return
(TAPVR)

Truncus arteriosus
These are the “classic” cyanotic heart diseases.
Cyanotic heart disease
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The fiveTs don't necessarily present the same, and
may not present with cyanosis.
Only transposition of the great arteries is associated
with severe cyanosis in the first hours of life. The
cyanosis occurs because the oxygenated pulmonary
venous blood can't reach the systemic circulation.
Cyanotic heart disease
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In the other lesions, the degree of admixture of the
“arterial” and “venous” blood determines the degree
of cyanosis.
If pulmonary blood is increased, patients with these
“admixture” lesions can have room air saturations of
90% or more.
Cyanotic CHD

Defects preventing right ventricular outflow can
present with earl cyanosis

Pulmonary atresia

Ebstein's anomaly (apical displacement of the
tricuspid valve into the RV decreases the amount
of blood that the RV can pump and also causes a
shunt across the atrial septum). Severe Ebstein's
can present in the DR or soon after.
The PDA
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Two topics: the PDA in the small premature infant
and the PDA in the infant with cyanotic heart
disease.
We will discuss the premie situation later...
The PDA
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The PDA acts to shunt blood to and from the
pulmonary and the systemic circulations. If the
ductal flow is high, the admixture can be enough to
minimize cyanosis.
Conversely when the ductus closes like it is
supposed to, the babies will begin to have
difficulties.
Heart Failure
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Due to excessive pulmonary blood flow or
inadequate systemic blood flow.
Large VSDs, endocardial cushion defects
(atrioventricular septal defects), or large PDA with
normal heart are associated with signs of heart
failure after the pulmonary vascular resistance drops,
as it is supposed to do in the days after birth.
Heart Failure
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Tachypnea
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Diaphoresis, especially of the forehead
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Poor feeding
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Failure to thrive
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Gallop rhythm on auscultation
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Hepatomegaly
Presenting as shock
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Infants with inadequate development of the left
ventricle will present with catastrophic heart failure
and shock as the ductus arteriosus closes.
The closure of the ductus results in decreased/ing
systemic blood flow.
The right heart is supplying the entire systemic
blood flow (HLH) or the systemic flow to the lower
body (coarctation, interrupted aortic arch)
Heart Failure
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In the nursery, the only sign of these lesions may be:

Single and loud S1 ,
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Increased precordial activity on palpation,
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Mildly abnormal postductal oximetry
Decreased femoral pulses usually not present until the
ductus closes
After the nursery and sometimes in it!
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Sepsis-like picture with poor color and perfusion
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Tachypnea
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Mottling
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Gray or cyanotic pallor
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Decreased central and peripheral pulses
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(This where assessment comes in again....and
sometimes it helps if someone says “could this be
cyanotic heart disease?”)
The premie ductus
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The ductus in the premie is supposed to close. When
it doesn't, the result is increased pulmonary blood
that we think causes increased oxygen needs,
increased rerspiratory support needs etc. If premie
has a PDA and we can't wean O2, vent, or CPAP we
blame the ductus and treat the duct with
Indomethacin or Ibuprofen
The premie ductus
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Both medications have side effects and require that
the baby be NPO for the duration of treatment and a
bit more.
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Gut perforation?
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Renal failure?
The Ductus in CCHD
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Keeping the ductus open will allow the admixture of
blood and will maintain systemic and/or pulmonary
blood flow
An intravascular infusion of Prostaglandin E1
(alprostadil)will keep the ductus open
Bonus points: where was alprostadil developed?
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Right down the street at Upjohn!
Assessment
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Look for other findings on exam that may suggest an
associated diagnosis

For example, trisomy 21 babies have an increased
incidence of AV canal defects and need an Echo to
rule out that diagnosis.
And now for some pictures, because they are easier to
understand.
Cincinnati Children's Hospital (U of Cincinnati)
and CS Mott Children's Hospital (U of M)
Both have great websites with nice pictures and
descriptions of the surgical repair options.
Normal Heart
Fetal Circulation
Persistent Pulmonary Hypertension
Transposition
TGA Repair
Tetralogy of Fallot
Tricuspid Atresia
Tricuspid Atresia
TAPVR
Total Anomalous Pulmonary Venous Return
Truncus Arteriosus
Hypoplastic Left heart
HLH Repair
Atrioventricular Septal Defect
AV Canal
Atrioventricular Septal Defect
AV Canal Valves
AV Canal Repair
Ebstein's Malformation
Coarctation of the Aorta
Ventricular Septal Defect
Thanks for your attention
Are there any questions?
References
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Any neonatal text
Hany A. Respiratory Disorders in the Newborn:
Identification and Diagnosis. Peds In Review,2004,
25(6):201-208
Silberbach M, Hannon D: Prsentation of Congenital
Heart Disease in the Infant and Young Infant. Peds
in Review, 2007,28(4):123-131
References
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AHA website
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Cincinnati Children's Hospital website
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U of M , Mott Children's Hospital website
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NIH website
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Texas Children’s Hospital/Texas Heart Institute
website