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Congenital Heart Defects
By Kimberly Napper
Congenital Heart Disease
occurs when the heart or blood
vessels near the heart do not
develop properly before birth.
Congenital Heart Defects
may include structural defects,
congenital arrhythmias, and
cardiomyopathies
• are present in about 1% of live
births
• are the most common congenital
malformations in newborns
•
Definitions of terms:
Atresia- congenital absence or closure of
a normal body opening or tubular
structure
 Prostaglandins- hormones important in
the mediation of inflammation, platelet
aggregation, vasodilation, pain reception,
& maintenance of patent ductus arteriosus
 Prostaglandin inhibitors- nonsteroidal
& steroid anti-inflammatory agents

Definitions of terms:
Stenosis- constriction or narrowing of a
passage or orifice
 Subacute Bacterial Endocarditis
(SBE)- heart valve infection not evident
for weeks or months; usually
streptococcal; often develops on
abnormal heart valve
 SBE prophylaxis- to prevent SBE

With Normal Heart Anatomy,
oxygen-depleted
blood is pumped
from the right side
of the heart,
through the
pulmonary artery,
to the lungs where
it is oxygenated.
http://en.wikipedia.org/wiki/Congenital_heart_defects
With Normal Heart Anatomy,
the oxygen-rich
blood then returns
to the left heart,
via the pulmonary
veins, and is
pumped through
the aorta to the
rest of the body.
http://en.wikipedia.org/wiki/Congenital_heart_defects
Normal Blood Flow
http://www.wellesley.edu/Biology/Courses/111/AdultHeart.gif
Fetal Circulation
(see Wong p. 823)
Umbilical vein supplies oxygen & nutrients
from the placenta
 Right side of heart has higher pressures
than left side
 Foramen ovale allows blood to cross from
right to left atrium
 Ductus arteriosus allows most of blood
from pulmonary artery to enter the aorta

Foramen Ovale
Transition from Fetal Circulation
Clamping of umbilical cord increases
systemic pressure
 Expansion of lungs with air
 Increased oxygen

– decreases pulmonary pressure (vasodilation)
– promotes closure of ductus arteriosus

Closure of foramen ovale as
left atrial pressure > right atrial pressure
Types of Congenital Heart Defects
(Classifications) Wong p. 824
Acyanotic-
left to right shunting of blood
(↑pulmonary blood flow)
Cyanotic-
right to left shunting of blood
(↓pulmonary blood flow)
Acyanotic Defects
(based on blood flow patterns within heart)
↑pulmonary flow
• ventricular septal
defect
• atrial septal defect
• patent ductus
arteriosus
obstruction to blood
flow out of the heart
 pulmonary stenosis
 aortic stenosis
 coarctation of the
aorta
Cyanotic Defects
(based on blood flow patterns within heart)
↓pulmonary flow
 Tetralogy of
Fallot
 Tricuspid Atresia
Mixed blood flow
• Transposition of
the Great Arteries
• Truncus Arteriosus
Acyanotic Defects
Blood Flow Patterns
with left to right shunting:
(↑pulmonary blood flow)
ventricular septal defect (VSD)
(30% of all congenital heart defects)
• atrial septal defect (ASD)
• patent ductus arteriosus (PDA)
•
Acyanotic Defects
Blood Flow Patterns
without shunting:
 pulmonary stenosis (PS)
 aortic stenosis (AS)
 coarctation of the aorta (coarc)
Acyanotic Defects
Blood Flow Patterns
•
Increased Pulmonary Flow
• ASD, VSD, PDA
•
Obstructed blood flow out of the
heart
• PS, AS, Coarc
Congenital Heart Defects
Blood Flow Patterns
Obstructed blood flow out of heart
 Coarctation of aorta
 Aortic stenosis
 Pulmonic stenosis
Mixed blood flow
 Transportation of the great vessels
 Truncus arteriosus
Congenital Heart Defects
Blood Flow Patterns
Increased pulmonary blood flow
Atrial and ventricular septal defects
 Patent ductus arteriosis

Decreased pulmonary blood flow
Tetralogy of Fallot
 Tricuspid atresia

Atrial Septal Defect (ASD)
 Abnormal
opening between the atria
 Allows blood from higher-pressure
left atrium to flow into lower-pressure
right atrium (left to right shunt)
 ↑pulmonary blood flow
 right heart dilation and pulmonary
overcirculation
ASD
 May
have no symptoms until later in life
 May have a soft systolic murmur
 Repair can prevent serious problems
later in life. (May lead to…)
– Heart Failure (HF)
– Atrial dysrhythmias
– Pulmonary vascular obstructive disease
– Emboli formation
Bubble Study to Confirm ASD

http://www.youtube.com/watch?v=3dssb
Deow50

http://youtu.be/3dssbDeow50
ASD
http://www.americanheart.org/images/ImagePicker/12998-inter-full.jpg
Left to Right Shunt
(Wong 9th ed. p. 825)
The blood from the left side is spilling back to the right side, which may “flood” the lungs!
http://en.wikipedia.org/wiki/File:Atrial_septal_defect-en.png
Transcatheter Closure of ASD
http://www.rjmatthewsmd.com/Definitions/atrial_septal_defect.htm
Transcatheter Closure of ASD
http://www.rjmatthewsmd.com/Definitions/atrial_septal_defect.htm
Ventricular Septal Defect (VSD)

Abnormal opening between the ventricles

Size & location of defect may vary

Allows blood from higher-pressure left ventricle
to flow into lower-pressure right ventricle
(left to right shunt)

↑pulmonary blood flow

Wong 9th ed. p.825, 826, 834
VSD
http://www.americanheart.org/images/ImagePicker/13026-inter-full.jpg
VSD

HF is common
 due to flooding of the lungs &
right ventricle ↑ load
Heart may enlarge
from the added work
 Murmur
(sound of turbulent blood flow)

Respiratory distress
“head bobbing” & retractions
http://www.youtube.com/watch?v=q0bHwM
ayCJY
 http://www.youtube.com/watch?v=NBA9iigi
Dgk

These are signs of respiratory distress!
 If R/T CHF, what medication should you give?

VSD
Wong 9th ed. p.825, 826, 834

Increased pulmonary blood flow will cause
prominent pulmonary vasculature (seen on CXR).

High blood pressure may occur in the lungs' blood
vessels (because more blood is there)

Over time, increased pulmonary hypertension may
permanently damage the blood vessel walls
VSD may exhibit increased pulmonary vasculature.
http://www.crkirk.com/thumbnail/common/vsd.htm
VSD on Echocardiogram
http://www.crkirk.com/thumbnail/common/vsd.htm
VSD

Small defects may close without surgery.

Small defects may be repaired surgically with a
purse-string approach.

Large defects may be repaired using a Dacron patch.

Cardiopulmonary bypass is required for surgical
repair.

Requires SBE prophylaxis until repaired.
Ventricular Septal Defect
http://www.medmovie.com/cardiac1/pages/0130iVSD.htm
After Heart Surgery
Growing up pretty!!
Growing strong!
Patent Ductus Arteriosus

The 6th most common congenital heart defect
(5 to 10% of all children with congenital heart disease)

Occurs twice as often in girls as in boys

Depending on the size of the PDA and the condition
of the lungs, there may be no symptoms or severe
heart failure.
http://www.congenitalheartdefects.com/typesofCHD.html#PDA
Patent Ductus Arteriosus
(PDA)
In utero, the ductus is a normal
connection between the aorta and
the pulmonary artery
 At birth, hormonal changes normally
cause its closure
 Failure to close may cause excessive
blood flow to the lungs

Patent Ductus Arteriosus
http://en.wikipedia.org/wiki/Image:Patent_ductus_arteriosus.jpg
Patent Ductus Arteriosus (PDA)
The pressure in the aorta is higher than
that of the pulmonary artery during both
systole and diastole.
 PDA blood shunting will occur from left to
right during both systole and diastole.
 The pulmonary arteries will dilate due to
the increased pulmonary blood flow

Blood Flow through Ductus
in Fetal Circulation
http://www.wellesley.edu/Biology/Courses/111/DuctArt.gif
Patent Ductus Arteriosus (PDA)
Wong 9th ed. p.827
S/S, if hemodynamically significant
 CHF/respiratory distress
– congestion in the lungs
– prominent pulmonary vascular markings seen
on CXR
Machinery-like murmur
 Widened pulse pressure
 Bounding pulses
 Pedal & periorbital edema

Pedal Edema in Infant
http://newborns.stanford.edu/PhotoGallery/FootEdema1.html
Patent Ductus Arteriosus (PDA)
May be “ligated” in surgery
 May be closed in cath lab by inserting
specially designed coils, which block blood
flow in the vessel
 May be closed medically with
Indomethicine (blocks Prostaglandins)

– Ibuprofen as an alternative (piloted in 2003)
PDA & Indomethacin
 Inhibition
of prostaglandin synthesis
permits constriction of the PDA
 FDA-approved Indomethicine for use:
– When S/S persist after 48 hours of
conservative treatment:
 fluid restriction, diuretics, and respiratory support.
– In premature infants weighing
500 to 1750 grams
PDA & Indomethacin
Less effective after 7 days of age
 Gastrointestinal problems

– abdominal distention
– bleeding
– gastric perforation
– transient ileus
– vomiting
Renal function impairment
 Bleeding problems
 Hypoglycemia

Patent Ductus Arteriosus (PDA)
Shunting of blood can also be right to left,
depending on the difference in pressures
between systemic & pulmonary circulation
 Blood flow will follow the path of least
resistance
 PDA may be life-saving in some cases
 Prostaglandin (PGE1) will be given IV to
keep ductus from closing in these cases

Prostaglandin E 1
Studies performed prior to the initiation of
prostaglandin therapy for central cyanosis:
 Hyperoxic Challenge Test
 Chest x-ray: Decreased pulmonary
vascularity
 Serum glucose
 Hematocrit
 Adequate ventilation
 Arterial Blood Gases
http://www.uihealthcare.com/depts/med/pediatrics/iowaneonatologyhandbook/pharmacology/prostaglandine1.html
Prostaglandin E 1
Definitive echocardiography and
cardiac catheterization will clearly identify
infants with ductal dependent
pulmonary blood flow
 Prostaglandin E1 is infused continuously
by pump via a large peripheral vein or
umbilical line.

http://www.uihealthcare.com/depts/med/pediatrics/iowaneonatologyhandbook/pharmacology/prostaglandine1.html
Echocardiogram for Diagnosis
Prostaglandin E 1

Monitor
– respiratory rate
– Temperature
– blood pressure
– arterial blood gases and pH

Three common side effects
– apnea (12%)
– fever (14%)
– flushing (10%)
Obstruction to Blood Flow
out of Heart
Obstruction defects
 An obstruction is a narrowing that partly
or completely blocks the flow of blood.
 Obstructions called stenoses can occur in
heart valves, arteries or veins.
 The three most common forms are
pulmonary stenosis, aortic stenosis and
coarctation of the aorta.
Pulmonary Stenosis (PS)





The pulmonary or pulmonic valve is between the
right ventricle and the pulmonary artery.
It opens to allow blood to flow from the right
ventricle to the lungs.
A defective pulmonary valve that doesn't open
properly is called stenotic.
This forces the right ventricle to pump harder
than normal to overcome the obstruction.
If severe, may be a cyanotic defect.
Pulmonary Stenosis (PS)
http://www.americanheart.org/images/ImagePicker/13014-inter-full.jpg
Pulmonary Stenosis (PS)
Treatment is needed when the pressure in
the right ventricle is higher than normal.
 In most children, the obstruction can be
relieved by a procedure called balloon
valvuloplasty.
 Others may need open-heart surgery.
 Requires SBE prophylaxis

Critical Pulmonary Stenosis/
Pulmonary atresia
No blood flow to lungs through pulmonic
valve (total fusion of commissures)
 Decreased pulmonary vasculature
(seen on CXR)
 Hypoplastic right ventricle may accompany
 Cyanosis if PDA closes
 PDA needed for survival until surgical
repair
 Prostaglandins to keep ductus open

Aortic Stenosis (AS)
A
normal valve has three leaflets
(cusps).
 A stenotic valve may have only one
cusp (unicuspid) or two cusps
(bicuspid), which are thick and stiff.
 The left ventricle will have difficulty in
pumping blood to the body through
this abnormal valve.
Aortic Stenosis
 Symptoms
may be severe in
some infants
 Most children have no symptoms
 Some children may have chest pain,
unusual tiring, dizziness or fainting
 The need for surgery depends on
how bad the stenosis is
Aortic Stenosis
 Valve
opening may be enlarged
by balloon valvuloplasty
or surgery.
 The valve will remain deformed.
 The valve may need to be
replaced with an artificial one.
Aortic Stenosis
 Lifelong
medical follow-up is required
 AS may worsen over time, and
surgical relief of a blockage is
sometimes incomplete
 Some exercise may be restricted (like
heavy lifting)
 SBE prophylaxis is required
The Aorta
The aorta is the body's main artery
 It distributes oxygen-rich blood to all parts
of the body except the lungs
 The first branches of the aorta go to the
upper body (arms and head)
 After that, blood goes to the lower body
(abdomen and legs)

Coarctation of the Aorta
Wong 9th ed. p. 827, 828

Is a narrowing of the aorta
between the upper-body
artery branches and the
branches to the lower body

May include aortic valve
abnormalities

May be associated with other
cardiac defects

SBE prophylaxis indicated
http://www.yourdictionary.com/images/ahd/
jpg/A4aorta.jpg
Coarctation of the Aorta
http://www.medmovie.com/cardiac1/pages/0088iCoarctAo.htm
Coarctation of the Aorta

Increases blood pressure in the arms and head
– Average B/P in a newborn is 64/41.
– Average B/P in a child 1 month - 2 years is 95/58.
Reduces blood pressure in the legs
 Diminished pulses in lower extremities
 Seriously strains the heart
 Leads to cardiomegaly
 Leads to CHF (heart failure)

Severe Coarctation of Aorta
In severe cases, cyanosis if PDA closes
 Patient needs PDA for survival until surgical
repair
 Prostaglandins (PGE1) to keep ductus open

Coarctation of the Aorta
Coarctation of Aorta

Balloon repair
– Risk of restenosis or aneurysm

Surgical repair
– Preferred in infants < 7 months
…but only for 10 minutes
Cyanotic Defects
(decreased pulmonary flow)
 Tricuspid
Atresia
 Tetralogy of
Fallot
Transposition of
the Great Vessels
 Truncus Arteriosus

Tricuspid Atresia
No tricuspid valve so no blood can flow
from the right atrium to the right ventricle
 Right ventricle is small and not fully
developed
 Survival depends on presence of ASD/VSD
 At birth, the PFO and PDA provide mixing
 Prostaglandin E1 to prevent ductal closure
prior to surgical repair

Tricuspid Atresia Blood Flow:
right atrium → ASD → left atrium →
 Most of this blood flows
left ventricle → aorta → body
 The rest flows through the
VSD → small right ventricle →
pulmonary artery → lungs
 Because of poor pulmonary circulation,
the child looks blue.

Tricuspid Atresia
http://www.americanheart.org/images/ImagePicker/13022-inter-full.jpg
Tricuspid Atresia repair
requires multiple procedures
Atrial septostomy in cath lab
 Pulmonary to systemic artery anastomosis
(Blalock and Taussig (BT) shunt)
 Bidirectional Glenn shunt at 6-9 months
(2nd stage)
 Modified Fontan procedure
 Wong 9th ed. p. 831

BT Shunt for Tricuspid Atresia
http://tarheelhemangiomas.tripod.com/sitebuildercontent/sitebuilderpictures/modifiedheart.jpg
Bidirectional Glenn Shunt for
Tricuspid Atresia
http://www.severinbrenny.com/shunt.jpg
http://www.severinbrenny.com/fontan_operation.html
Nursing Considerations
re: Tricuspid Atresia repair
No blood pressures or venipunctures in
left arm of patients who had Glenn
procedure (left subclavian artery used)
 Family support & teaching regarding
multiple surgeries & mortality rate ~10%

Tetralogy of Fallot
4 Key Features:
1.
Ventricular Septal Defect (a hole between the ventricles)
2.
Pulmonary Stenosis
(obstruction from the right ventricle to the lungs)
3.
Overriding Aorta (the major artery from the heart to the
body lies directly over the ventricular septal defect)
4.
Right Ventricular Hypertrophy (thickened muscle develops)
Tetralogy of Fallot

Boot-shape on CXR

Often blue (cyanotic) since some oxygen-poor blood is
pumped to the body

Blood from both ventricles (oxygen-rich and oxygen-
poor) is pumped into the body since the aorta overrides
the ventricular defect and there's pulmonary stenosis

May have pulmonary atresia
(pulmonary valve completely obstructed)
Tetralogy of Fallot
http://www.americanheart.org/images/ImagePicker/13020-inter-full.jpg
Tetralogy of Fallot
boot-shape on CXR
http://pediatriccardiology.uchicago.edu/MP/Radiology/cxrtof.htm
Surgical Treatment of
Tetralogy of Fallot
In small and very blue infants, a shunt
operation may be done first to provide
adequate blood flow to the lungs.
 The shunt is built between the aorta and
the pulmonary artery
 The shunt is removed when a complete
intracardiac repair is done later

http://www.americanheart.org/presenter.jhtml?identifier=11071#
“Tet Spell” (hypercyanotic spell)

Wong 9th ed. p.841
http://affinity-health.adam.com/graphics/images/en/18134.jpg
Tetralogy of Fallot
Knee-Chest Positioning to relieve “Tet Spells”
http://www.bing.com/images/search?q=squatting+with+tetralogy+of+fallot&go=&qs=bs&form=QBIR&adlt=strict#view=detail&id=A56E
12D9B28879308E21CF630E9D1FA90638B697&selectedIndex=6
Tetralogy of Fallot &
Squatting Position
http://www.bing.com/images/search?q=squatting+with+tetralogy+of+fallot&go=&qs=bs&form=QBIR&adlt=strict#view=detail&id=3D6
3338F1039662ADDA61062F2CD9243B68ECAF3&selectedIndex=233
Before First Surgery
Steri-Strips at Sternotomy Site
Years
Later
As she grew, her
shunt was no
longer big enough
to provide
sufficient blood
flow to her lungs.
It was time for her
“big girl” surgery.
Mixed blood flow
 Transportation
of the Great Vessels
 Truncus Arteriosus
Transposition of the
" Great Vessels”
 Vena
cavae
 Pulmonary artery
 Pulmonary veins
 Aorta
http://en.wikipedia.org/wiki/Great_vessels
Transposition of the
Great Vessels or Great Arteries

“Egg on a String” on CXR

Aorta comes off RV (right ventricle)

Pulmonary Artery comes off LV

Cyanosis
– Less severe if large ASD, VSD, or PDA
– CHF if ASD, VSD, or PDA

Patent Foramen Ovale (PFO) commonly present
Transposition of Great Arteries
with “egg on a string” CXR
http://pediatriccardiology.uchicago.edu/MP/Radiology/cxrtga.htm
Transposition of Great Arteries
(TGA)

PDA, PFO, & septal defects allow mixing of blood
(to get flow to the lungs)

Prostaglandins to keep ductus open, if no other means
of mixing left & right circulation (Wong 9th ed. p. 832)

Balloon Atrial Septostomy to establish mixing

Surgical switch of vessels
Transposition of Great Vessels
http://www.medmovie.com/cardiac1/pages/0120iRashkindBaby.htm
Transposition of the Great Arteries
http://www.medmovie.com/cardiac1/pages/0125iTransArtSurg.htm
Truncus Arteriosus

Boot shape on CXR

Single vessel that overrides both ventricles
– pulmonary artery & aorta share a trunk

Blood from left & right mix in single vessel

Hypoxemia

↑ pulmonary flow (R/T pressures)

↓ systemic blood flow (R/T pressures)
Truncus Arteriosus
Truncus Arteriosus

Surgical repair in first month of life
– Closure of VSD
– Grafts to connect pulmonary arteries to
right ventricle
Truncus Arteriosus

Post repair complications
– CHF common
– Pulmonary hypertension
– Dysrhythmias
– Mortality >10%
– Future surgeries required to replace conduits
Developmental Care of the Sick Infant
http://dev.snoedel.com/wpcontent/uploads/2012/12/snoedel_nicu.jpg
http://www.babyfirst.com/en/neonatal-care/developmental-care.php#
Support infant’s limbs
to promote flexion
Promote Bonding
Wong 9th ed. p 843
 Allow parents to hold baby, if stable enough
 Encourage parents to touch & stroke their baby
 Point out nice features of baby
 Do not focus solely on child’s illness
 Allow parents to participate in care
 Listen to parents grieve & support them

Kangaroo Care
holding a diaper-clad
infant in skin-to-skin
contact, prone and
upright on the chest of
the parent.
• Infant enclosed in
parent’s clothing to
maintain temperature
stability.
Recommended for
• Medically stable infants
• Infants receiving palliative
care
•
http://www.adhb.govt.nz/newborn/Guidelines/Developmental/KangarooCare.htm
Complications of
Congenital Heart Defects
Bacterial Endocarditis
 Pulmonary Hypertension
 Congestive Heart Failure
 Arrythmias
 Emboli

Bacterial Endocarditis.

When blood is pumped at high pressure through
defects, the lining of the heart tissue will
become irritated and inflamed

Bacteria in the bloodstream can easily infect this
injured area, causing a serious illness known as
bacterial endocarditis
“SBE Prophylaxis”
(Subacute Bacterial Endocarditis)
http://www.americanheart.org/presenter.jhtml?identifier=11086
“SBE Prophylaxis” indicated for:

All cyanotic heart lesions, especially those with systemic-
to-pulmonary shunts in place

All post-operative coarctation patients, whether surgically
repaired or after balloon dilation

All those with valvar abnormalities, whether congenital,
rheumatic, or with prosthetic valve in place

VSD patients: the more smaller the VSD, the higher the
chance of SBE
http://nips.med-web.com/Handouts/Individual%20Pages/Jenny's%20Handouts/j-sbe.htm
Pulmonary Hypertension

Large volumes of blood pumped to the lungs →
high pressure

Blood vessels in the lungs become damaged by the extra
pressure

Pressure builds up in the lungs → ↓ blood flow from the
left heart to the right heart (preserves lung function)

Blood flow in the heart goes from areas of high pressure
to areas of lower pressure
Pulmonary Hypertension and
“Shunting” right to left

If defects causing high blood flow to lungs persist,
lung disease will develop

Pressure in the right heart will become higher than in
the left heart

Oxygen-poor blood will flow from the right side of the
heart (via ASD/VSD/PDA) into the left side (and out to
the body)
Pulmonary Hypertension and
“Shunting” right to left
When there is an opening or passage between the atria,
ventricles, and/or great vessels
… and …
Right heart pressure is higher than left heart pressure
Congestive Heart Failure

Right-sided failure
if difficult to pump blood to pulmonary artery
↑pressure develops in right atrium &
systemic venous circulation
→ hepatosplenomegaly & edema
Congestive Heart Failure
Caused by conditions that require the
heart muscle to work hard
 Failure of one side of heart leads to failure
of the other side due to reciprocal changes
 Presenting symptoms may vary

Impaired myocardial function
Pulmonary congestion
Systemic venous congestion
Congestive Heart Failure
Tachypnea
 Tachycardia (at rest)
 Dyspnea
 Retractions
 Activity Intolerance (poor feeding)
 Enlarged liver
 Enlarged heart on CXR (& on EKG)
 ↑pulmonary blood flow on CXR

Congestive Heart Failure
Treatment Goals (Wong 9th ed. p 836)
↓ afterload by vasodilation (ACE inhibitors)
 ↑ cardiac contractility (glycoside: Lanoxin)
 ↓ preload by removing excess fluid &
sodium (diuretics: Lasix & thiazides)
 ↓ cardiac demands (rest & homeostasis)
 Improve tissue oxygenation & ↓ oxygen
consumption (O2 administration)

Heart Failure & Failure to Thrive
Poor weight gain
 Expends too much energy & calories
trying to breathe & eat
 Feedings should be appropriate to child’s
developmental stage
 Wong 9th ed. p 391
 Wong 9th ed. p 840

Oral medication administration
How to Give Oral Medication to an Infant

Aim the medicine toward the back near the gums or
cheeks, but not at the back of the tongue.

Squirt medicine into the mouth in small amounts.
or

Place a clean nipple into the baby's mouth and then put
the medicine into the nipple and let the baby suck the
medicine through the nipple.
http://www.ehow.com/how_2068060_give-baby-medicine.html
Also, look in Wong p. 718-719 re:
oral medication administration for infants.
Break Time!!