pharmacotherapy of congenital heart disease

1. PEDIATRICS CONGENITAL HEART DISEASE
Jimma university
School of pharmacy
Getandale zeleke[B.pharm,clinical pharmacy,MSC,pg2 ]
1
getandale@gmail.com; getandale.zeleke@ju.edu.et

2. Presentation outline
 Introduction
 The epidemiology
 Classification of congenital heart disease
 Pathophysiology
 Clinical presentation and physical findings of common CHD
 management
2

3. INTRODUCTION
3

4. Foetal circulatory system
4

5. Foetal Circulation
Arterial blood leaves the placenta
via the umbilical vein
This branches and delivers blood
to the IVC by way of the ductus
venosus
Blood then goes into the right
atrium, 30% goes across the
foramen ovale, the rest to the RV
then to PA
Instead of going to the lungs, 85%
goes through the PDA to the aorta

6. INTRODUCTION
6
 Is a defect in the structure or function of the heart and great
vessels which is present at birth.
 Congenital heart disease (CHD) is the most common
congenital disorder in newborns.
 It is not static ,there is always a continuous anatomical or
physiological change

7. Epidemiology and Genetic Basis of
Congenital Heart Disease
 Congenital heart disease occurs in approximately 0.8% of live births.
 The incidence is higher in stillborns (3-4%), spontaneous abortuses
(10-25%), and premature infants.
 In preterm infants, CHD is two to three times that found in term
infants.
 about 2-3 in 1,000 newborn infants will be symptomatic with heart
disease in the 1st year of life
 With advances in both palliative and corrective surgery, the number
of children with CHD surviving to adulthood has increased
dramatically.
 Despite these advances, CHD remains the leading cause of death in
children with congenital malformations.
7

8. Prevalence of Congenital heart
Disease (chart review)
DevelopedDeveloped
countriescountries
Ethio-SwedishEthio-Swedish TAHTAH
VSDVSD 28.3%28.3% 4141 28.4%28.4%
PDAPDA 12%12% 13%13% 16.5%16.5%
ASDASD 10.7%10.7% 13.6%13.6% 13%13%
COACOA 8.8%8.8% <2%<2% 1.8%1.8%
TOFTOF 7%7% 9%9% 5.7%5.7%
PSPS 6%6% 9.9%9.9% 8.8%8.8%
ASAS 2.3%2.3% 3.5%3.5% 3.4%3.4%

9. Etiology
 The cause of most congenital heart defects is unknown.
 thought to be multifactorial and result from a combination of
genetic predisposition and environmental stimulus
 CHD are related to chromosomal abnormalities, in particular,
trisomy and Turner syndrome.
 Third Pregnancy 20-30%
 The risk of recurrence of CHD increases if a 1st-degree relative
(parent or sibling) is affected.
9

10.  Of all cases of CHD, 2-4% are associated with known
environmental or adverse maternal conditions and
teratogenic influences, including
maternal diabetes mellitus,
phenylketonuria, or
systemic lupus erythematosus;
congenital rubella syndrome;
 and maternal ingestion of drugs (lithium, ethanol, warfarin,
thalidomide, antimetabolites, vitamin A derivatives,
anticonvulsant agents.
10

11.  Gender differences in the occurrence of specific cardiac
lesions have been identified.
 Transposition of the great arteries and left-sided obstructive
lesions are slightly more common in boys (≈65%),
 whereas atrial septal defect, VSD, PDA, and pulmonic
stenosis are more common in girls.
11

12. Evaluation of the newborn

13. Recognition of Cyanosis
Cyanosis = blue color of skin and mucous membranes caused by
reduced oxygen content
oxygen content of blood depends upon:
Hgb level
oxygen saturation
blood flow
cyanosis usually noted when Sat’s <86%
cyanosis more difficult to see in anemia
13

14. Central cyanosis
• noted in the trunk, tongue, mucous membranes
• due to reduced oxygen saturation
Peripheral cyanosis
• noted in the hands and feet, around mouth
• due to reduced local blood flow
Recognition of Cyanosis

16. Acyanotic Congenital Heart
Disease
↑Pulmanary blood flow
Left-to-Right Shunt Lesions
 Patent Ductus Arteriosus (PDA)
 Atrial Septal Defect (ASD)
 VentricularSeptal Defect (VSD)
 Atrioventricular Septal Defect (AV Canal)
 The pathophysiologic common denominator in this group
is communication between the systemic and pulmonary
sides of the circulation, which results in shunting of fully
oxygenated blood back into the lungs

17.  The direction and magnitude of the shunt across such a
communication depend on the size of the defect, the relative
pulmonary and systemic pressure and vascular resistances.
 The increased volume of blood in the lungs decreases
pulmonary compliance and increases the work of breathing.
 Fluid leaks into the interstitial space and alveoli and causes
pulmonary edema.
 The infant acquires the symptoms we refer to as heart
failure, such as tachypnea, chest retractions, nasal flaring,
and wheezing.
17

18. Patent Ductus Arteriosus
 PDA – Persistence of the normal fetal vessel that
joins the Pulmonary artery to the Aorta.
 Normally closes in the 1st
wk of life.
 Female:Male ratio of 2:1
 associated with maternal rubella infection during
early pregnancy
 PDA is a common problem in
premature infants.

19. Pathophysiology
 As a result of the higher aortic pressure postnatally, blood
shunts left to right through the ductus, from the aorta to the
pulmonary artery.
 The extent of the shunt depends on the size of the ductus
and on the ratio of pulmonary to systemic vascular
resistance.
 If the PDA is small, pressures within the pulmonary artery,
the right ventricle, and the right atrium are normal.
 If the PDA is large, pulmonary artery pressure may be
elevated to systemic levels during both systole and diastole
19

20. Patent Ductus Arteriosus
Hemodynamics
 As a result of higher aortic
pressure, blood shunts L to
R through the ductus from
Aorta to PA.

21. Clinical Manifestations
 A small PDA is usually asymptomatic.
 tachycardia
 Shortness of breath
 Retardation of physical growth.
 Characteristic systolic-diastolic
murmur at the base of the heart with
maximum in the PA
21

22. Patent Ductus Arteriosus
 Classic continuous machine-like
murmur
 It begins soon after onset of the 1st sound,
reaches maximal intensity at the end of
systole, and wanes in late diastole.
 prominent apical impulse
enlarged heart,
 Left subclavicular thrill
 Bounding pulse
Clinical Signs & SymptomsClinical Signs & Symptoms

23. • pulmonary
vascularity is
increased;
• enlargement of
left sided heart
Chest X-ray

24. THERAPEUTIC
INTERVENTIONS
Interventions for PDA closure include:
Pharmacologic therapy, which is used exclusively in premature
infants
Surgical ligation
Percutaneous catheter occlusion
Mortality is < 1%

25. Pharmacologic therapy
Inhibitors of prostaglandin synthesis, such as indomethacin and
ibuprofen , are used as the initial interventions for PDA closure in
preterm infants.
Indomethacin -0.2 mg/kg
Ibuprofen -10-5-5 mgkg
ibuprofen is as effective as indomethacin in closing a PDA and
currently appears to be the drug of choice. Ibuprofen reduces the
risk of NEC and transient renal insufficiency. Oro-gastric
administration of ibuprofen appears as effective as iv administration
25
Cochrane Database Syst Rev. 2015 Feb
18;(2)

26.  Paracetamol is as effective as indomethacin and ibuprofen
in closure of PDA in preterm neonates and
has less side effects mainly on renal function, platelet count,
and GIT bleeding.
26
Eur J Pediatr. 2017 Feb;176(2):233-
240
Trials. 2016 Apr 2;17:182

27. Surgery
 Irrespective of age, patients with PDA require surgical
or catheter closure
 The surgical approach and technique are dependent
upon the size and age of the patient
 The following complications are associated with
surgical closure
Recurrent laryngeal nerve paralysis
Respiratory compromise
Infection
Intracranial hemorrhage in preterm infants
27

28. Percutaneous closure
 provides an alternative to surgical ligation in patients
beyond infancy
 Access is generally achieved through the femoral artery or
vein.
 Closure of the PDA with coil or device without thoracotomy
28

29. Indications for PDA closure
 PDA closure for patients with a significant left-to-right
shunt who are symptomatic, have evidence of left cardiac
overload (ie, left atrial or ventricular enlargement), or have
mild to moderate pulmonary arterial hypertension (PAH) .
 for patients with a previous episode of endocarditis
regardless of the size of PDA in the absence of severe PAH
29

30. Atrial Septal Defect
ASD is an opening in the atrial septum permitting free
communication of blood between the atria
 Atrial septal defects (ASDs) can occur in any portion of the
atrial septum (secundum, primum, or sinus venosus), depending
on which embryonic septal structure has failed to develop
normally
30

31. There are 3 majortypes:
Se cundum ASD – at the Fossa Ovalis, accounts for 70
to 75 percent of all ASDs,most common.
• Prim um ASD – lower in position
accounts for 15 to 20 percent of ASDs.
• Sinus Ve no sus ASD – high in the atrial septum,
the least common.
31

32. Atrial Septal Defect
 Secundum ASD  Sinus Venosus ASD

33. In normal, the chambers of the left side of the
heart are higher pressure than of the right side;

34.  In the case of a large ASD (>9mm), may result in left-to-
right shunt, blood will shunt from the LA to the RA.
 This extra blood may cause a volume overload of both the
right atrium and the right ventricle.
 Ultimately the RV must push out more blood than the LV
due to the L-to-R shunt.
 This condition can result in eventually RV-failure
(dilatation and decreased systolic function) and Pulm Htn.
34

35. Atrial septal defect
with left-to-right shunt
 When the pressure in the RA rises to the level in the LA,
the left-to-right shunt will diminish or cease.
 When the pressure in the RA to be higher than the pressure
in the LA and will reverse the shunt → right-to-left shunt
will exist (this phenomenon is known as Eisenmenger’s
syndrome).

36. Clinical Signs & Symptoms
•Most infants with ASDs are asymptomatic.
•They may present at 6 to 8 weeks of age with a soft systolic
ejection murmur
•Hyperactive precordium, RV heave, fixed widely split S2.
•Mid-diastolic murmur heard over LLSB.
•Children with large left-to-right shunts are likely to complain of
some fatigue and dyspnea.
•Growth failure is very uncommon
36

37. Clinical Signs & Symptoms
• Rarely presents with signs of CHF or other cardiovascular
symptoms.
• Most are asymptomatic but may have easy fatigability or
mild growth failure.
• Cyanosis does not occur unless pulmonary HTN is present.
37

38. Radiologic Features
Echo-CG: RV is enlarged, defect is visualized
The heart is usually enlarged, with a cardiothoracic ratio >0.5
chest X-ray: pulmonary vascularity is increased
38

39. NATURAL HISTORY
 Secundum ASDs can close spontaneously, remain
unchanged, or enlarge.
 Spontaneous closure, or a decrease in size, is most likely to
occur in defects less than 7 to 8 mm in diameter and with
younger age at diagnosis
39

40. TREATMENT
 The treatment for isolated secundum ASD is closure of the
defect, which can be achieved by a surgical or percutaneous
transcatheter approach.
Which ASDs should be closed?
The majority of isolated secundum ASDs <6 mm diameter in infants
close spontaneously by 2 years, and some as late as 5 years of
age.
Thus, in the absence of associated symptoms, early closure is not
indicated for these defects.
Defects of moderate size (at least 6 to 8 mm in diameter) and larger
are relatively unlikely to close spontaneously.
40

41.  However, closure of even moderate and large isolated
secundum ASDs is not recommended in asymptomatic patients
before 2 years of age due to the possibility, however small, of
spontaneous closure.
 The accepted clinical standard is to repair Surgical or
catherization closure for secundum ASD w/ a Qp:Qs ratio
>2:1
 Surgical correction is done earlier in children w/ CHF or
significant Pulm HTN.
 prophylactic antibiotics are recommended for dental and
respiratory tract procedures during the first six months after the
repair.
41

42. Ventricular Septal Defect
 VSD– is an abnormal opening in the ventricular
septum, which allows free communication between the
Rt & Lt ventricles.
 Accounts for 25% of CHD.
42

43. Ventricular Septal
Defect
 During systole some of the blood from the LV leaks into the RV,
passes through the lungs and reenters the LV via the pulmonary
veins and LA.
 Such circuitous route of blood causes volume overload on the
LV.
 The LV normally has a much higher systolic pressure (~100 mm
Hg) than the RV (~85 mm Hg) and through VSD blood leaks
into the RV and elevates RV pressure and volume, causing
PulmHTN.

44. 4 Types
Perimembranous (or membranous) – Most common(80%).
defect lies in the outflow tract of the left ventricle immediately
beneath the aortic valve
Muscular VSD – Defects in the muscular septum are frequently
multiple and make up 5% to 20% of defects found at surgery
Infundibular (subpulmonary VSD) – involves the RV outflow tract.
Defects in the outflow tract of the right ventricle beneath the
pulmonary valve
AVSD – inlet VSD, posterior and inferior to the membranous
defect, beneath the septal leaflet of the tricuspid valve almost always
involves AV valvular abnormalities
44

45. Clinical Signs & Symptoms
 Small - moderate VSD, 3-6mm, are usually asymptomatic
and 50% will close spontaneously by age 2yrs.
 Moderate – large VSD, almost always have symptoms and
will require surgical repair.
 harsh holosystolic murmur heard along the LSB, more
prominent with small VSD, may be absent with a
very Large VSD
 Prominent P2, Diastolic murmur.
 CHF, FTT, Respiratory infections, exercise intolerance
 hyperactive precordium.
 Symptoms develop between 1 – 6months
45

46.  If the defect is large and pulmonary vascular resistance is not
significantly elevated (L-t-R-shunt)
– growth failure, CHF, repeated lower respiratory tract
infections (begin at 1-2month);
 If the defect is large and pulmonary vascular resistance is very
high (Eisenmenger’s reaction) – shortness of breath,
dyspnea on exertion, chest pain, cyanosis;
46

47. Chest X-rayChest X-ray::
• increased pulmonaryincreased pulmonary
vascularity,vascularity,
• enlargement of theenlargement of the
LA and LV;LA and LV;
Ventricular Septal Defect

48. CXR: progressive dilatation of heartCXR: progressive dilatation of heart..
• cardiomegalycardiomegaly
• increasedincreased
pulmonarypulmonary
vascularity,vascularity,
• enlargementenlargement
of the LA andof the LA and
LVLV;;

49. Treatment: Medical Therapy
 Children with small VSDs are asymptomatic and have excellent
long-term prognosis.
 Neither medical therapy nor surgery is indicated.
 Bacterial endocarditis prophylaxis is indicated
 If children with moderate or large VSDs develop symptomatic
congestive heart failure,a trial of medical therapy is indicated.
 Furosemide is used in a dosage of 1 to 3 mg/kg/day divided into
two or three doses
 Systemic afterload reduction with enalapril (initial dosage of 0.1
mg/kg/24 hours divided into twice daily, gradually increasing to 0.5
mg/kg/24hours divided into twice daily dose, maximum of 40
mg/day)
49

50. Indications forSurgical
Closure:
Large VSD w/ medically uncontrolled symptomatology
& continued FTT(failure to thrive).
Ages 6-12 mo w/ large VSD & Pulm. HTN
Age > 24 mo w/ Qp:Qs ratio > 2:1.
Supracristal VSD of any size, secondary to risk of
developing AV insufficiency
50

51. Acyanotic Congenital Heart Disease
Obstruction to blood flow from
ventricles
 Coarctation of the Aorta
 Pulmonary Stenosis
 Aortic Stenosis
51

52. Coarctation of the Aorta
 Coarctation- Coarctation of the aorta is a narrowing
of the descending aorta, which is typically located at
the insertion of the ductus arteriosus.
 occurs in approximately 6% to 8% of patients with
congenital heart disease
 coarctation occurs more commonly in males than in
females.
 The genetic component to coarctation has long been
recognized in the Turner syndrome, in which about
35% of patients are affected

53. PATHOGENESIS AND ETIOLOGY
Congenital.
The vast majority of coarctation cases are congenital.
the two main theories for the development of congenital
coarctation of the aorta are:
 Reduced antegrade intrauterine blood flow causing
underdevelopment of the fetal aortic arch.
 Migration or extension of ductal tissue into the wall of the fetal
thoracic aorta
There is also increasing evidence of a vascular wall defect in the
ascending aorta of individuals with congenital coarctation of aorta
53

54. Acquired
 In addition to a congenital etiology, aortic narrowing can be
an acquired abnormality due to inflammatory diseases of the
aorta, such as Takayasu arteritis or, rarely, severe
atherosclerosis
the former disorder, the midthoracic or abdominal aorta is
often the site of involvement
54

55. Coarctation of the Aorta
Hemodynamics
 Obstruction of left ventricular outflow ⇒ LV afterload
increases ⇒ pressure hypertrophy of the LV.

56. Feel the pulses
especially brachial and femoral
Clinical Signs &Clinical Signs &
SymptomsSymptoms
• Classic signs of
coarctation are
diminution or
absence of femoral
pulses..
• Pulse discrepancyPulse discrepancy
between rt & lt arms.between rt & lt arms.
Coarctation of the Aorta

57. Clinical Signs & Symptoms
Higher BP in the upper extremities as compared to the
lower extremities.
90% have systolic hypertension of the upper extremities.
Pulse discrepancy between rt & lt arms.
57

58. ….
 Sings of low cardiac output, poor peripheral
perfusion – Lower extremities hypoperfusion,
acidosis, HF and shock
 Differential cyanosis if ductus is still open
 systolic ejection murmur @ LSB.
 Cardiomegaly, rib notching on X-ray
58

59. Coarctation of the Aorta

60. Treatment
 untreated, coarctation of the aorta has a poor natural history.
 natural history data for untreated coarctation documented a
mean age at death of 34 years,75% of patients died by 46
years of age.
 The most common causes of death were congestive heart
failure (26%), aortic rupture (21%), bacterial endocarditis
(18%), and intracranial hemorrhage (12%)
60

61. Cont…
 Management decisions for patients with coarctation of the aorta
depend upon patient age, presentation, and the severity of the
lesion.
 Critical coarctation in infancy: Infants with severe
(“critical”) coarctation are at-risk for developing heart failure
and death when the ductus arteriosus closes.
 Identification of these patients is essential in order to maintain
patency of the ductus prior to surgical repair.
 immediate treatment is required to stabilize patients with heart
failure.
61

62. Medical therapy consists of the following:
Continuous intravenous infusion of prostaglandin E1 (also known
as alprostadil ) to keep the ductus arteriosus open.
Dopamine and/or dobutamine to improve contractility in those
with heart failure.
Supportive care to correct metabolic acidosis, hypoglycemia,
respiratory failure, and anemia that may contribute to or be a
consequence of heart failure.
The introduction of prostaglandin E1 ( alprostadil) has significantly
decreased the mortality in neonates with critical coarctation
Once the patient is stabilized, surgical repair can be performed.
62
Pediatr Cardiol. 2004 Jan-
Feb;25(1):49-52.
Pediatr Cardiol. 2006 Nov-
Dec;27(6):766-8

63. Surgical Repair
 Surgical repair remains the conventional treatment for most
children with coarctation of the aorta.
 The types of surgical repair of coarctation include:
Resection with end-to-end anastomosis
Subclavian flap aortoplasty in infants with long-segment
coarctation
A bypass graft across the area of coarctation when the
distance to be bridged is too long for an end-to-end repair
Prosthetic patch aortoplasty, which is avoided whenever
possible because of the frequent occurrence of aortic
aneurysm or rupture
63

64. Balloon angioplasty
Balloon angioplasty is a noninvasive alternative to
surgical repair for older infants (greater than four months
of age) and young children with native discrete
coarctation.
 It remains the preferred intervention for all patients
with isolated recoarctation regardless of age
64

65. Pulmonary Stenosis
 Pulmonary Stenosis is obstruction in the region of either the
pulmonary valve or the subpulmonary ventricular outflow tract.
 Accounts for 7-10% of all CHD.
 Most cases are isolated lesions
 Can present w/ or w/o an intact
ventricular septum
 Maybe biscuspid or fusion of 2 or
more leaflets.
65

66. Hemodynamics
 RV pressure hypertrophy ⇒ RV failure.
 RV pressures maybe > systemic pressure.
 Post-stenotic dilation of main PA.
 W/intact septum & severe stenosis ⇒ R-L shunt through PFO
⇒ cyanosis.
 Cyanosis is indicative of Critical PS.
66

67. Clinical Signs & Symptoms
 Most patients with valvar pulmonary stenosis are
asymptomatic
 Depends on the severity of obstruction.
 Asymptomatic w/ mild PS < 30mmHg.
 Mod-severe: 30-60mmHg, > 60mmHg
Prominent jugular a-wave, RV lift
Split 2nd
hrt sound w/ a delay
Ejection click, followed by systolic murmur.
Heart failure & cyanosis seen in severe cases.
67

68. Treatment
 Mild PS no intervention required, close follow-up.
 Mod-severe – require relieve of stenosis.
 Balloon valvuloplasty, treatment of choice.
 Surgical valvotomy is also a consideration
68

69. Balloon Dilatation
of Pulmonic Valve

70. Aortic Stenosis
 Aortic Stenosis is an obstruction to the outflow from the left
ventricle at or near the aortic valve that causes a systolic pressure
gradient of more than 10mmHg. Accounts for 7% of CHD.
 more dangerous lesion compared to PS
3 Types
 Valvular – Most common.
 Subvalvular(subaortic) – involves the left
outflow tract.
 Supravalvular – involves the ascending aorta
is the least common.
70

71. Clinical Signs & Symptoms
 Mild AS may present with exercise intolerance, easy
fatigabiltity, but usually asymptomatic.
 Moderate AS – Chest pain, dypsnea on exertion, dizziness &
syncope.
 Severe AS – Weak pulses, left sided heart failure, Sudden
Death.
71

72.  LV thrust at the Apex.
 Systolic thrill @ Rt base/suprasternal notch.
 Ejection click, systolic murmur @ RSB/LSB w/
radiation to the carotids.
72

73. Treatment
 Because surgery does not offer a cure it is reserved for
patients with symptoms and a resting gradient of 60-
80mmHg.
 For subaortic stenosis it is reserved for gradients of 40-
50mmHg because of it’s rapidly progressive nature.
 Balloon valvuloplasty is the standard of treatment.
73

74. .
 Aortic insufficiency & re-stenosis is likely after surgery and
may require valve replacement.
 Activity should not be restricted in Mild AS.
 Mod-severe AS, no competitive sports
74

75. Cyanotic Congenital Heart Disease
 There has to be a RIGHT to LEFT shunt to cause cyanosis.
 Congenital heart disease produces cyanosis when obstruction
to right ventricular outflow causes intracardiac right-to-left
shunting.
 Complex anatomic defects cause an admixture of pulmonaryComplex anatomic defects cause an admixture of pulmonary
and systemic venous return in the heartand systemic venous return in the heart
 Decreased pulmonary blood flowDecreased pulmonary blood flow
 Chest X-RayChest X-Ray
Decreased pulmonary vascular markingsDecreased pulmonary vascular markings
75

76. Tetralogy of Fallot
Most common cyanotic heart disease.
The four abnormalities include:
Pulmonary stenosis
RVH
VSD
Overriding Aorta
Signs include cyanosis, murmur,
squatting and spells.

76

77. Pathophysiology:
Increased resistance by
the pulmonary stenosis causes
deoxygenated systemic venous
return to be diverted from RV,
through VSD to the overriding aorta
and systemic circulation
systemic hypoxemia and cyanosis
77

78. Clinical Signs & Symptoms
Symptoms are variable depending of degree of obstruction
 Cyanosis – is variable (isn’t present at the birth, occurs later
in the 1st
yr of life)
 Tet spells(Hypercyanotic ): irritability, cyanosis,
hyperventilation and sometimes syncope or convulsions due
to cerebral hypoxemia
 Severe dyspnea on exertion
 Tachycardia
 Mental retardation
 Retarded growth and development
 RV heave
 Systolic ejection murmur is heard along the left sternal
border
78

79. Chest X-RayChest X-Ray
• DecreasedDecreased
pulmonary vascularpulmonary vascular
markingmarking
• ““Boot-shapedBoot-shaped
heart”heart”

80.  Treatment of tetralogy of Fallot depends on the severity of the
right ventricular outflow tract obstruction.
 Infants with severe tetralogy require urgent medical treatment and
surgical intervention in the neonatal period.
 Decrease cardiac workload
 Hypercyanotic “tet” spells may require rapid and aggressive
treatment that starts with placement of the patient in a knee-chest
position to increase systemic vascular resistance, which promotes
movement of blood from the right ventricle into the pulmonary
circulation rather than the aorta.
80

81.  This may be followed by more aggressive therapy of intravenous
morphine and a fluid bolus. The mechanism of action of morphine
is unclear, while fluids improve RV filling and pulmonary flow.
 If the above measures fail, intravenous beta blockers (eg,
propranolol or esmolol) can be administered.
The goal is to control the magnitude of the right to left intracardiac
shunt, which is increased by:
Decreased SVR
Increased PVR
Increased myocardial contractility
 Surgical closure of the VSD and enlargement of the pulmonary
outflow tract.
81

82. d-Transposition of the Great Arteries

83.  The aorta arises from the right ventricle and
the pulmonary artery from the left.
 The mixing of the blood occurs at the
PFO and the PDA.
The signs include cyanosis
and cardiomegaly.
 Reverse differential cyanosis!
 There may be no murmur.
 An echocardiogram is diagnostic.
83

84. d-Transposition of the Great
Arteries
 Pathophysiology
 Cyanosis due to failure of delivery of pulmonary venous
blood to the systemic circulation
 Two parallel circulations with no mixing
 Open atrial septum (fossa ovalis) allows some left-to-right
shunt, enhanced by a left-to-right ductus arteriosus shunt
 Presence of ventricular septal defect facilitates mixing
84

85.  Heart failure often present.
 Cardiac enlargement and diminished pulmonary artery
segment on x-ray.
 Untreated, the vast majority of these infants would not
survive the neonatal period.
85

86. Clinical Manifestations
 Cyanosis, tachypnea are most often recognized within the 1st
hrs or days of life.
 Hypoxemia is usually moderate to severe, depending on the
degree of atrial level shunting and whether the ductus is
partially open or totally closed.
 Physical findings, other than cyanosis, may be remarkably
nonspecific.
 Murmurs may be absent, or a soft systolic ejection murmur
may be noted at the midleft sternal border.
86

87.  Chest film
 Oval-shaped heart
 Narrow mediastinum
 Normal or increased pulmonary vascular markings
 This condition is a medical emergency, and only early diagnosis
and appropriate intervention can avert the development of
prolonged severe hypoxemia and acidosis, which lead to death
87

88. Treatment
When transposition is suspected, an infusion of prostaglandin E1
(0.05 microg/kg per minute) should be initiated immediately to
maintain patency of the ductus arteriosus and improve
oxygenation.
Infants who remain severely hypoxic or acidotic despite
prostaglandin infusion should undergo balloon atrial septostomy
88

89. .
89

90.  .
90

91. prophylaxis for infective
endocarditis
 The recommendation for antimicrobial prophylaxis for dental and other
procedures (and others) is now limited to those patients with cardiac
conditions with the highest risk of IE
 Today, antibiotics before dental procedures are only recommended for
patients with the highest risk of IE, those who have:
 Cyanotic congenital heart disease, that has not been fully repaired,
including children who have had a surgical shunts and conduits.
 A congenital heart defect that's been completely repaired with
prosthetic material or a device for the first six months after the repair
procedure.
 Repaired congenital heart disease with residual defects, such as
persisting leaks or abnormal flow at or adjacent to a prosthetic patch or
prosthetic device.
91

92.  prosthetic heart valve or who have had a heart valve
repaired with prosthetic material.
 A history of endocarditis.
 A heart transplant with abnormal heart valve function
.
92
Circulation 2007; 116:1736

93. Preventing Birth Defects
 Stop smoking
 Avoid drinking alcohol while pregnant
 Take a daily vitamin containing folic acid
 Check with your doctor to make sure any medication (over-
the-counter or prescription) is safe to take during
pregnancy
 Stop use of any illegal or "street" drugs

94. References
 Moss and Adams; Heart Disease in Infants Children and
Adolescents,7th
edition.
 Nelson Textbook of Paediatrics 20th
edition.
 Uptodate 21.2
 Primary literatures mentioned in the body of this document.
94

95. The END
Are we going to use acetaminophen for PDA
closer?

96. Thank you
for attention!