congenital heart diseases by yilgwan.ppt

Congenital heart diseases

1. Congenital heart diseases
By
Dr CS Yilgwan
Department of Paediatrics
University of Jos

2. Intro
•Congenital heart disease(CHD) is defined as
any structural, functional or positional
abnormality of the heart in isolation or in
combination that is present from birth and
may or may not manifest any time thereafter.

3. Incidence
•Incidence varies from region to region even
within a country
•4-8 per thousand live births
•Higher in still births and abortuses
•8 lesions combine account for 80% of
cases(VSD-32%, PDA-12%, TOF-6%, PS-8%,
ASD-6%, CoA-6%, TGA-5%, AS-5%)

4. Aetiology
•Largely unknown
•Multifactorial inheritance
-genetic eg chromosomal defects
-environment eg intrauterine infections
•Maternal obesity, DM
•Male sex
•High altitude predisposing to PDA, ASD

5. Classification
•Cyanotic
•Acyanotic

6. Acyanotic
•Volume overload-shunt vascularity with
increase PVM
•-ASD(atrial septal defect)
•-VSD(ventricular septal defect)
•-PDA(patent ductus arteriosus)
•-AVCD

7. •Pressure overload-Normal vascularity usually
obstructive in nature
•-PS(pulmonary stenosis)
•-AS(aortic stenosis)
•-CoA

8. Cyanotic
•Volume overload-shunt vascularity
•-TGA
•-TAPVR
•-Persistent truncusarteriosus
•Pressure overload-decrease vascularity
•-TOF(tetralogy of fallot)
•-TA(truncus arteriosus)
•-Ebsteinanomaly

9. ASD
•Any opening in the atrial septum other than a
competent foramen ovale
•Three types
•-ostiumsecundum-commonest(70%) present
at the site of fossaovalis
•Ostiumprimum(30%)-superior or roof of the
atrium
•Ostiumvenosus(10%) occurs at point of entry
of SVC

10. Pathophysiology
•Left to right shunt
•Dilatation of right sided chambers and
pulmonary bed engorgement
•Shunt volume is dependent on the relative
compliance of the RV, thus in foetal and
neonatal life, minimal or no shunt occur
because of stiffness of RV

11. Clinical features
•Asymptomatic in infants and younger children
•Only notice at about 6-8wks of life as soft
ejection murmur, widely split S2
•Large shunt manifest in older children as
fatigue and exertional dyspnea
•Growth failure is uncommon

12. ECG
•RAD
•RVH
•RBBB with prolonged PR
•+/-Tall P waves

13. Radiograph
•Prominent MPA
•Prominent pulmonary vascular markings
•RAE, RVH

14. ECHO
•Demonstrate the shunt
•RAE, RVH
•Shunt flow pattern on Doppler echo

15. mgt
•Medical-treat CCF(congestive cardiac failure)
•Catheter closure
•surgical

16. VSD
•Most common heart lesion
•20% of all isolated lesions and atleast 30-40 of
combinations

17. Types
•Membranous
•muscular

18. Natural hx
•Small lesions-asymptomatic
•Moderate to large lesions-
•-repeated pulmonary infections
•-easy fatigability
•-exercise intolerance
•-CCF
•-Failure to thrive
•-PAH
•Unoperated
-PAH
-SHUNT REVERSAL
-decreased level of activity
Central cyanosis

19. features
•Holosystolic murmur
•Features of CCF
•Hyperdynamic praecodium
•Loud single P2 with PAH

20. ECG
•Moderate size-LVH, LAE, dilated MPA
•Large VSD, combine ventricular hypertrophy

21. Radiograph
•Cardiomegaly
•Dilated MPA
•LVH,LAE
•Increased PVM

22. echo
•Show lesion
•Dilated chambers
•Shunt volume and pattern

23. Natural hx
•Spontaneous closure in 30-40% of small size
•CCF from 4-8 weeks
•Large VSD may give rise to PVOD may set in as
early as 6-12 months of age
•Arrhythmias
•IE

24. Mgt
•Medical-treat CCF
•Catheter
•surgical

25. •CYANOTIC HEA-RT LESIONS

26. RVO obstruction with R-L shunting at ventricular
level (TOF, DORV with PS)
•Physiologic alterations and severity of hypoxaemia
depend on severity of RV outflow obstruction (PS) and
the potential effects of SVR, volume and gravity.
•In uteroeffect on fetal circulatory pathway include small vertical ductusarteriosusand
increased blood flow via the aortic isthmus.
Postnatal physiology include
=Progressive increase in RVO obstruction > worsening
hypoxaemia>polycythaemiaand complications (below).
=Elevations in SVR, hypovolemia, and postural changes >
hypercyanoticspells (see below).
=Intermittent infundibularspasm > hypercyanoticspells
Adaptativemechanisms
•RV hypertrophy due to increased afterload
•Increased RBC mass (effect erythropoietin on BM)
•Hyperpnoea due to chemoreceptor stimulation (hypoxia)
•Increased 2, 3 DPG leads to increased O
2delivery
•Chronic hypoxaemiaand acidosis impairs growth
(Decreased growth decreases oxygen demand. )

27. Tetralogy of fallot
•Fifth most common CHD and the commonest
CCHD beyond neonatal period
•Maternal PKU and trimethadione has been
shown to increase the risk of TOF
•Result from incomplete rotation and faulty
partitioning of conotruncus during septation

28. Pathology
•Large VSD
•RHH
•PS or RVOTO
•Overriding aorta
•Right sided aortic arch in 25%

29. Pathophysiology
•RVOTO determines the degree of shunting
•Non restrictive VSD
•Exercise increases shunting leading to
decrease saturation and worsening cyanosis

30. Manifestation
•Cyanosis by 6-8weeks of life
•Exertional dyspnea, squatting and tet spells as
the child grows older
•Clubbing
•Systolic click
•Ejection systolic murmur at LUSB

31. •ECG
•-RVH+RAD
•-+/-RAH

32. Radiograph
•Normal size heart
•Boot shaped heart
•Oligaemic lung fields
•Right sided aortic arch

33. Transposition of the great arteries
•It is lethal especially when it occurs without
any shunt lesion
•Accounts for 5-7% of CHDs
•Without treatment about 30% will die in the
1
st
week of life, 50% in the first month, 70%
within 6 months, 90% in the first year of life
•60% male preponderance
•VSD is the commonest associated lesion

34. Transposition Physiology
The fundamental physiologic alterations include
•Parallel outputs of systemic RV and pulmonary LV necessitating shunting to sustain life
(IVS, IAS, DA level)
•O
2 saturation depends on magnitude of mixing b/w syst.
and pulm. circulations.
•PBF is variable (normal, increased or decreased).
•In uterofetal circulatory dynamics are maintained.
•Postnatallylimited mixing leads to severe hypoxaemiaand cyanosis at birth.
•Increased mixing is associated minimal hypoxaemiabut signs of severe CCF in the
neonatal period
=Adaptativeresponse
•Limited mixing>acute hypoxaemia>hyperneaor tachynea>redistricutionof CO.
•Chronic hypoxaemia>increased RBC mass; increased 2,3-DPG and potential for PVOD.

35. Complications
•NEC
•PVOD usually after successful palliative
surgery
•Polycythaemia with possibility of stroke
•Brain abscess

36. Investigation
•ECG
-RAD, RVH,CVH
-DYSRHYTHMIAS
•RADIOGRAPH
-EGG ON SIDE SILHOUTTE
-Increase PVM
•Echo
•Lesion
•Effects

37. Natural hx
•Progressive hypoxia and acidosis resulting in
death with early onset CCF in first week of life
•In the presence of a shunt, cyanosis is less
marked but CCF is more marked with early
onset PVOD if surgery not done before 3
rd
month of life
•Without a shunt lesion, prognosis is very grim
and 80% die in the first weeks of life

38. Mgt
•Correction of acidosis
•Treat hpocalcemia and hypoglycemia
•Start PGE at birth to keep PDA patent in case
of intact septum
•Give O2 for severe hypoxia
•Arterial switch surgery (Jatene procedure) is
the choice surgery

39. Common Mixing Lesions
•Main physiologic alterations include admixing of systemic and pulmonary blood.
•Hypoxaemiais minimal unless PS coexists.
•Systemic and pulmonary venous congestion develop and
potentially > PVOD
•Normal fetal cardiovacularperformance & flow pathways
•Postnatally, rate of fall in PVR or presence of PS direct
the clinical course.
•Signs of SV and PV congestions are dominant with atrial
and ventricular chamber volume overload.
•Mixing at atrial level runs a more benign course than ventricular or great artery
mixing.
Adaptativemechanisms (or maladaptative)
•Increased RBC mass and 2,3 DPG; slow growth, early
development of PVOD except with mixing at atrial level
•PS may develop postnatally.

40. Ductal dependent CHD (Critical RVO or LVO obstruction)
•In utero ductal patency is maintained by relative hypoxia and high levels of PGE
1. placental
source.
•At birth SaO
2 rises & PGE
1 ,fallseffecting ductal closure.
•Critical LVO or RVO obstruction or underdevelopment will
require PDA/ VSD /ASD to provide blood flow to the
systemic or pulm. circulation.
•Functional closure of DA 72 hrs after birth will affect
syst. or pulm. circulation if critical obstruction is present.
•Postnatal effects include circulatory collapse, cyanosis and CCF at birth.
Examples
Critical LVOT obstruction > shock and CCF at birth
(critical AS, HLHS, hypoplastic, critical CoA)
•Critical RVOT obstruction > acute cyanosis at birth.
(pulm. atresia with intact IVS, TOF with pulm atresia,
severe PS, tricuspid atresia with very restricted PBF)

41. Pathophysiology of Chronic Hypoxaemia in CCHD
Reduced SaO
2 > central cyanosis or 1
0
hypoxaemia.
CCHD > chronic hypoxaemia.
Adaptative(compensatory) effects of chronic hypoxaemia:
•Vascular response to hypoxaemia
Hypoxia > vasoconstriction in pulm. vessels (high PVR)
and vasodilatation in systemic vessels (high SVR) >
increase R-L shunting and chronic & severe hypoxaemiain CCHD with PS + VSD.
Metabolic acidosis 2
0
severe hypoxaemia> vasodilationand sustains the vicious cycle.
•Chronic hypoxaemiastimulates secretion of renal
erythropoietin >erythroblastosisand polycythaemia>
improvement on blood O
2 carrying-capacity.
•But above haematocritof 65%, blood viscosity increases
exponentially with polycythaemia> increase in both SVR
and PVR (++) > increased afterloadon the ventricles RV (++) > increased R-L shunting >
worsening hypoxaemia>cascade of reactions.

42. Complications of Chronic Hypoxaemia
•Clubbing (after 6 months or more)
•Growth failure plus delayed reproductive maturation
•Hypoxic spells and squatting typical in TOF
•Iron deficiency anaemia2
0
erythrocytosis( suggested by normal or <normal Hband hypochromia)
•Bleeding disorders
(thrombocythopenia, defective platelet aggregation, prolonged PT & PTT, low levels of factors V & VIII and
fibrinogen)
•Chest pain (reduced coronary arterial BF> ischaemicheart changes).
•CNS complications (CVA, brain abscess).
•Depressed intelligent quotient
•Hyperuricaemiagout
•Scoliosis (expansion of bone marrow of vertebral bodies, bone resorption2
o
to ischaemicchanges
from chronic hypoxaemia)

43. Dr. CAN Okoromah_CMUL
•Hb levels influence clinical detection of cyanosis. At least 5 gram of
desaturated Hb per 100 ml of blood required to produce clinical
cyanosis.
=Normal (Hb 15gm%) at SaO
2 75-85%
=Polycythaemia (Hb 20gm%) at SaO
2 80-85%
=Anaemia (Hb 6 gm%) at SaO
2 45-50%