Download CONGENITAL HEART DISEASE

10/18/2012
CONGENITAL HEART DISEASE
Touching the Future of Children
October, 2012
Case Scenario #1

A 16 day old infant is transferred to a Level IV NICU
 Hx:
NSVD at 34 weeks, features of Trisomy 21 noted and
confirmed by karyotype, remained hospitalized due to
poor feeding, murmur noted on DOL #6
 Current: Tachypneic, hypotonic, poor weight gain
 Exam: Weight 15% below birthweight, RR= 90, mildmod retractions, pale, diaphoretic with crying

What issue(s) might you suspect?

Case Scenario #2

A term infant is delivered with prenatal diagnosis of
CHD
 Fetal
echo report: Transposition of the great vessels with
a small-moderate inlet VSD. Foramen ovale appeared
non-restricted at time of echo
 Infant arrives to NICU at 17 minutes of age in RA, color is
slightly dusky with sat probe on left foot reading 71%.
Resp effort easy, good tone
 What
are priorities of care at this time??
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Case Scenario #3

A 3 day old male infant is found limp and
cyanotic in Mom’s room on postpartum unit
 Hx:
Poor PNC, C/S for breech, fed OK on DOL 1 & 2
but very sleepy today
 Taken
to NBN and transferred to NICU
 Infant
tachypneic, no retractions, pale, gray color,
femoral pulses barely detected, Sats = 66% despite
100% BBO2

What do you suspect to be the diagnosis?
Congenital Heart Disease

Incidence
 6-8
/ 1000 live births
children diagnosed per year
 25% considered “critical CHD”
 40,000

Classification: based on physiology of the
defect
Fetal Development
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Embryology



Development occurs Day 18 through 12th week of
fetal life
Heart beat detectable Day 21-25
Stages:
 Cardiac
tube
 Septation
 Valve
 Great
formation
vessel development
Teratogenesis

85% attributed to multifactorial causes
 Genetic


predisposition coupled with a causative factor
Genetic factors
Environmental factors
 AEDs:
phenytoin, carbamazepine,
 Anticoagulants
 Antineoplastics
 Lithium
Teratogenesis

Environmental factors
 Retinoic
acid
– FAS
 Amphetamines
 Alcohol

Maternal disease
 Diabetes:
 Maternal
5 x greater risk with IDDM
lupus
 Rubella
 CMV
 Maternal
obesity
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Cardiac assessment








Color
Heart rate and rhythm
Resp rate and effort
Blood pressures: 4 extremities
Peripheral pulses
Perfusion: central and peripheral
Precordial activity
Pulse oximetry
 Response
to oxygen
CHD Screening with Pulse Ox




Late detection of CCHD increases morbidity and
mortality
2010: HHS recommends universal screening pulse
oximetry screening
2011: Endorsed by AAP
Directed at detection of specific lesions:
 HHLS,
Pulmonary atresia, TOF, TAPVR, TGA, Tricuspid
atresia, Truncus arteriosus

Will not detect all CHD: acyanotic, some left heart
defects
CHD Screening with Pulse Ox


Must establish acceptable ranges and abnormal
threshold
Perform after 24 hrs of life
 Late


as possible with early D/C
Use a motion-tolerant pulse oximeter
Site: right hand and either foot (pre & post ductal)
 Simultaneous


or sequential
Performed by qualified personnel
Timely evaluation of infants with abnormal screen
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10/18/2012
Nurse-driven algorithm
Hines (2012) Advances in Neonatal Care Vol. 12, No. 3
CHD Presentation:








CHF
Cyanosis
Shock; decreased CO
Murmur
Tachypnea
+/- resp. distress
Dysrhythmia
Abnormal heart size, shape, location
Terminology

Murmur: Sound produced by turbulent blood flow
 May
be: Nonpathological
Pathological
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10/18/2012
Murmurs

Timing
Systolic: between S1 and S2 of same beat
Diastolic: between S2 and S1 of next beat
 Continuous: Starts in systole and ends in diastole



Intensity: Grade 1 - 6
I: barely audible
II: soft, but audible
 III: moderate, but no thrill
 IV: loud and/or associated with thrill
 V: stethoscope barely touching chest
 VI: rare in countries with organized health care


Murmurs

Nonpathologic / benign
 Common
in first week of life
systolic murmurs
 Grade I-II
 No associated s/s
 Normal CXR
 Short
Murmurs

Pathological
≥
Grade 3
quality
 Diastolic or continuous murmurs
 Abnormal S2
 Associated symptoms
 CXR
 Harsh
 Abnormal
 Increased
size or shape of heart
or decreased pulmonary vascular markings
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10/18/2012
Murmurs

However…..
 ~20%
of neonates with CHD do not have a murmur!
Physiology of absent murmur:
- Low turbulence
- Decreased ventricular function
- Elevated pulmonary vascular
resistance limits flow
Terminology

Murmur: A sound produced by turbulent blood flow
 Nonpathological
 Pathological

Shunt:
 via
defect or persistent fetal structure
direction?
 Which
Normal Heart
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10/18/2012
Shunt: Left to Right



From left heart (or aorta) to right heart (or PA)
A systemic to pulmonary shunt
Oxygenated blood recirculated to right side of the heart
Shunt: Right to Left


From right heart (or PA)
into left heart (or aorta)
Deoxygenated blood
mixing into oxygenated
blood
Shunt: Right to Left


A pulmonary to
systemic shunt
Results in systemic
desaturation and
cyanosis
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10/18/2012
Most Common CHD







VSD: Ventricular Septal Defect
ASD: Atrial Septal Defect
CoA: Coarctation of the Aorta
PS : Pulmonary Stenosis
AS: Aortic Stenosis
TOF: Tetrology of Fallot
TGV: Transposition of Great Vessels
Physiology of CHD

Acyanotic
 Issue:

Increased pulmonary blood flow
Cyanotic
 Issue:
 Not
Central cyanosis with low arterial saturation
ductal dependent
dependent
 Ductal

Left outflow tract obstruction CHD
 Obstruction
 Issue:
to systemic blood flow
circulatory collapse / shock
CHD
18%
Acyanotic
Cyanotic
24%
57%
Left Heart Obstruction
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Physiology of CHD

Acyanotic
 Issue:

Increased pulmonary blood flow
Cyanotic
 Central

cyanosis with low arterial saturation
Left outflow tract obstruction CHD
 Obstruction
to systemic blood flow
Acyanotic CHD


Left to right shunt
Oxygenated blood re-circulated to pulmonary bed
 Volume and pressure overload

S/S of pulmonary overload / CHF

Long term risk of pulmonary hypertension
Ventricular Septal Defect



Incomplete division of R
& L ventricles
MOST common CHD
Incidence 1-5:1,000
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VSD - types




Perimembraneous
Supracristal,
infundibular, conal, or
subpulmonary
Inlet
Muscular
Endocardial Cushion Defect
(AV Canal)


Malformations in
development of
endocardial cushion
Abnormal central heart:
ASD
VSD
 Tricuspid valve
 Mitral valve


Endocardial Cushion Defect
AV Canal


Potential for mixing among
all 4 chambers
NB period: PVR increased


Balanced shunting or mild
cyanosis possible
When PVR drops (2-4 wks)


LR shunt dominates
Pulmonary overload, CHF,
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Acyanotic CHD: Clinical Presentation

Varies with spectrum of defect

Active precordium

Resp. distress

Diaphoresis

Activity intolerance

Resp infections

Growth failure

Murmur

Hepatomegaly

CXR: Possible cardiomegaly, RA, RV
enlargement, Increased pulmonary
markings
Acyanotic CHD: Management

Monitor closely

Manage CHF:

Nutrition:
 NG




feeds if fatigued
calorie formula
 High
Fluid restriction
Inotropes: Digoxin,
Dobutamine
Diuretics
Oxygen


SBE prophylaxis
Immunizations
Palliative Surgery

PA banding procedure
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Acyanotic CHD: Repair

Surgical repair



Patch closure
Valvuloplasty
Timing varies
Categories of CHD

Acyanotic
 Issue:

Increased pulmonary blood flow
Cyanotic
 Central

cyanosis with low arterial saturation
Left outflow tract obstruction CHD
 Obstruction
to systemic blood flow
Cyanotic CHD

Common Defects:
 Transposition
of Great Vessels (TGV)
of Fallot (TOF)
 Truncus arteriosus
 TAPVR
 Tetrology

Require immediate intervention
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Cyanotic CHD

Cyanosis due to:
 Mixing
blood
of deoxygenated blood into oxygenated
? shunt
OR
 Obstruction
of pulmonary blood flow
Case Scenario #3

Previously well newborn infant presenting with
cyanosis:
What is the differential diagnosis?
Previously Well NB

Fetal shunts
 Ductus
Arteriosus
Ovale
 Foramen

May allow compensation in
first days of life
Ductus Arteriosus
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10/18/2012
Fetal Shunts


Significant deterioration
when shunts close
Screening for CHD with
pulse ox before
discharge from NBN

Endorsed by HHS and AAP
Foramen Ovale
Transposition of Great Vessels

Aorta arises from RV
Pulmonary artery from LV

Parallel circulations


Some shunt (VSD, PFO,
PDA) essential for survival
TGV
TGV with IVS
TGV with VSD
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10/18/2012
TGV

Presentation:
 Cyanosis
 Tachypnea
 Murmur

CXR:
 Cardiomegaly
 “Egg
on string”
PVM
 Narrow mediastinum
 Increased
Transposition

Diagnosis





Echocardiogram
Stabilization
Prostaglandin E (PGE,
Alprostadil) to open ductus
arteriosus
Maintain sats >75%
Palliation

Balloon septostomy



If foramen is restricted
Increases mixing
Repair

Arterial switch procedure
Tetrology of Fallot (TOF)
1.
2.
3.
4.
VSD
RV hypertrophy
Over-riding aorta
RV outflow tract
obstruction
(Spectrum of minimal >> severe
pulmonary stenosis / atresia)
“Pink Tet” or “Blue Tet” ??
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Tetrology of Fallot (TOF)

Presentation:
 Variable
cyanosis
 Murmur
 CXR:
 Boot
shaped heart
PVM if pulmonary
outlet obstruction severe
 Decreased
“Pink Tet” or “Blue Tet” ??
Pulmonary Atresia
Severe Pulmonary Stenosis




Pulmonary valve
obstruction
RV hypoplasia
Most have ASD or
Patent Foramen Ovale
Pulmonary blood flow
via ductus arteriosus
Pulmonary atresia
Severe pulmonary stenosis

Presentation
 Variable
cyanosis at
birth
 Murmur
 Single S2
 Critically ill as ductus
arteriosus closes
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Pulmonary atresia / TOF with PS

Newborn Stabilization
 PGE (Alprostadil) to open ductus and provide
pulmonary blood flow
 Creates
a __________ shunt through DA
 Maintain
sats >75%
 Treat acidosis
 Respiratory support
Prostaglandin




Prostaglandin E
PGE1
Prostin VR Pediatric®
Alprostadil
PGE / Prostaglandin
Maintains patency of ductus arteriosus
 Action: Causes vasodilation by direct
action on vascular and ductal smooth
muscle


Half life 5-10 minutes: Continuous IV infusion
 Critical


thinking???
Metabolism: lungs → active metabolite
Elimination: renal
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Administration


Initial dose – 0.05 – 0.1 mcg/kg/min
Assess closely for response (max effect ~30 min)



Increased oxygenation
Decreased metabolic acidosis
Titrate dose to lowest effective dose:
 0.01
– 0.05 mcg/kg/min
Side effects











Apnea
Fever
Flushing
Rash
Irritability
Hypotension
Bradycardia
Muscle twitching
Diarrhea
Hypoglycemia
Inhibits platelet aggregation
P. Atresia / TOF with P. atresia

Palliation
 Blalock-Taussig
 Modified
shunt
BT shunt
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Categories of CHD

Acyanotic
 Issue:

Increased pulmonary blood flow
Cyanotic
 Central

cyanosis with low arterial saturation
Left outflow tract obstruction CHD
 Obstruction
 Issue:
to systemic blood flow
circulatory collapse / shock
Left Heart Obstructive CHD

Includes: CoA, Critical AS, Interrupted arch, HLHS

Obstruction to aortic blood flow

May initially look well

Deterioration; CV collapse when ductus closes
 Newborn

appears GRAY
Ductal dependent for systemic blood flow
 Creates
Rt to left shunt through DA
Coarctation of the Aorta

Narrowing of aorta

Common at area of DA

May include
hypoplastic aortic arch,
other CHD
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Coarctation – Presentation



BP higher in upper
extremities
Pulses greater in upper
extremities
Decreased perfusion to
GI organs, kidneys
Coarctation - Surgery

Left subclavian flap
Coarctation - Surgery

Oblique resection
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Aortic stenosis



Obstructed aortic valve
May have LV
hypoplasia and poor LV
function
Ductal dependent for
systemic blood flow and
what else? ________
Hypoplastic left heart syndrome
(HLHS)

Spectrum of conditions:







small LV
aorta & mitral valve atresia or
stenosis
LA smaller than normal
hypoplasia of ascending aorta &
arch
Obstruction to systemic blood
flow
LV output almost nil
Ductal dependent CHD
Left Heart Obstruction

Goals:
 Improve systemic
perfusion
 Reverse effects of
shock, acidosis
 Treat CHF
 Balance PVR and SVR
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Left Heart Obstruction
 Balance
PVR and SVR
 Avoid
pulmonary
vasodilation


Cautious administration of O2
Vigilant fluid balance
 Avoid
systemic
vasoconstriction




Avoid inotropes with alpha
effect
May use afterload reduction
 Milrinone, Nipride
Vigilant fluid balance
Monitor renal and GI status
Left Heart Obstruction

Stabilization:
 Ventilation
 PGE
infusion
sats 75-85%
 Treat acidosis
 Cautious volume
resuscitation
 Inotropes for poor
myocardial fxn
 Dobutamine
 Milrinone
 Maintain
Categories of CHD

Acyanotic
 Issue:

Increased pulmonary blood flow
Cyanotic
 Central

cyanosis with low arterial saturation
Left outflow tract obstruction CHD
 Obstruction
to systemic blood flow
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General Nursing Care

Understand patient’s defect
 Blood
flow patterns
issues: CHF?, Cyanosis?
 Plan of care: palliation?, staged repair, full repair?
 Expected

Know baseline vital signs
 Normal
heart rate, BP for status
O2 saturation, blood gas values
 Baseline
General Nursing Care

IV Access
 Unrepaired
Cyanotic or Obstructive Defects:
NO AIR IN IV LINES!
Risk of air embolus

Oxygen administration
 Understand
 Discuss
physiology and possible effects
plan for acute desaturation
General Nursing Care

Correct metabolic acidosis

Ensure adequate fluid balance

Monitor urine output, renal function

Prevent cold stress in infants

Involve and support parents
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Summary: CHD

Acyanotic
 Often

with increased pulmonary blood flow
Cyanotic:
 Mixing

– OR - decreased pulmonary blood flow
Left outflow tract obstruction CHD
 Obstruction
to systemic blood flow
Case Scenario #1

A 16 day old infant is transferred HMC from another
NICU.
 Hx:
NSVD at 34 weeks, features of Trisomy 21 noted and
confirmed by karyotype, remained hospitalized due to
poor feeding, murmur noted on DOL #6
 Current: Tachypneic, hypotonic, poor weight gain
 Exam: Weight 15% below birthweight, RR= 90, mildmod retractions, pale, diaphoretic with crying

What issue(s) might you suspect?

Case Scenario #1

A 16 day old infant is transferred HMC from another
NICU.

Differential diagnosis:

Care:
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10/18/2012
Case Scenario #2

A term infant is delivered with prenatal diagnosis of
CHD
 Fetal
echo report: Transposition of the great vessels with
a small-moderate inlet VSD. Foramen ovale appears
non-restricted at time of echo
 Infant arrives to NICU in RA, color sl dusky with sats =
71% in RA. Resp effort easy, good tone
 What
are priorities of care at this time??
Case Scenario #2


A term infant is delivered with prenatal diagnosis of
TGV
What are priorities of care at this time??
Case Scenario #3

A 3 day old male infant is found limp and
cyanotic in Mom’s room on WH unit
 Hx:
Poor PNC, C/S for breech, fed OK on DOL 1 & 2
but sleepy today
 Taken
to NBN and transferred to NICU
 Infant
tachypneic, no retractions, pale, gray color,
femoral pulses barely detected, Sats = 69% despite
100% BBO2

What do you suspect to be the diagnosis?
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10/18/2012
Case Scenario #3

A 3 day old male infant is found limp and
cyanotic in Mom’s room on WH unit

Thank you!
References








Kaplan et al.. 2005. Effect of Prenatal Diagnosis on Outcome in Patients With Congenital Heart
Disease. Neoreviews; 6: 326-331.
Karlsen, K. & Tani, L. STABLE Program: Cardiac Module: Recognition and stabilization of
neonates with severe CHD. 2003. The Stable Program, Park City, UT.
Khoo, N.S. et al. 2008. Effectiveness of Prenatal Diagnosis of Congenital Heart Defects in South
Australia: A Population Analysis 1999-2003. Australian and New Zealand Journal of Obstetrics
and Gynaecology (Volume 48 Issue 6, December 2008)
Khoshnood, B. et al. 2005. Trends in Prenatal Diagnosis, Pregnancy Termination, and Perinatal
Mortality of Newborns With Congenital Heart Disease in France, 1983–2000: A PopulationBased Evaluation PEDIATRICS Vol. 115 No. 1 January 2005, 95-101.
Knight, S. & Washington, R. 2006. Cardiovascular Diseases and Surgical Interventions. In In
Handbook of Neonatal Intensive Care. 6th edition. Merenstein & Gardner, eds. Mosby Elsevier.
Meckler GD, Lowe C. To intubate or not to intubate? Transporting infants on prostaglandin E1.
Pediatrics. 2009;123:e25—e30.
Sadowski, S. 2010. Cardiovascular Disorders. In Core Curriculum for Neonatal Intensive Care.
4th edition. Verklan & Walden, eds. Saunders Elsevier.
Sendelbach DM, Jackson GL, Lai SS, Fixler DE, Stehel EK, Engle WD. Pulse oximetry screening at
four hours of age to detect critical congenital heart disease. Pediatrics. 2008;122:e815–e820.
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