principle of CHD

1. Dr.Azad A Haleem AL.Brefkani
University Of Duhok
Faculty of Medical Science
School Of Medicine
Pediatrics Department
azad82d@gmail.com
2015

2. Main Aspects of Lecture
• Anatomy of heart
• Physiology
• Embryology
• Change of circulation with age
• CHD
• History and Examination
• Important Investigations
• Classifications

3. • The heart is the central pump of the cardiovascular system that drives blood
through the blood vessels.
• It is a muscular structure, which is made up of four chambers.
Two atria (right and left) which are separated from each other by the
interatrial septum.
Two ventricles (right and left) which are separated from each other by the
interventricular septum
The human heart contains four valves
Two atrioventricular valves (AV valves) between the atria and the
ventricles:
o Tricuspid valve between the right atrium and the right ventricle.
o Mitral valve between the left atrium and there left ventricle.
Two semilunar valves:
o Aortic valve between the left ventricle and the aorta.
o Pulmonary valve between the right ventricle and the pulmonary trunk.
The heart

4. 4
Flow chart

5. Blood flow from the heart
• During ventricular systole, blood is pumped into
the circulation.
• During diastole, the pumping of blood stops and
the ventricles get filled with blood.
• In this way, the flow of blood from the ventricles
into the systemic and pulmonary circulations is an
intermittent pulsatile flow.

6. Cardiac output
 Cardiac output is the blood flow generated by
each ventricle per minute.
• The cardiac output is equal; to the volume of
blood pumped by one ventricle per beat × the
number of beats per minute:
Q = SV × HR
Where Q = cardiac output, SV = stroke volume, and
HR = heart rate.

7. Major derivatives of the embryonic germ layers

8. Embryological development
• Development of the heart including Cardiac Septum
&Development of Main Blood Vessels(Arterial &
Venous) start during 4th week & completed by end of
6th week of Embryonic life.
• Day 22 heart starts pumping

9. Fetal Circulation
• For the fetus the placenta is the oxygenator so
the lungs do little work
• RV & LV contribute equally to the systemic
circulation and pump against similar resistance
• Shunts are necessary for survival
– ductus venosus (bypasses liver)
– foramen ovale (R→L atrial level shunt)
– ductus arteriosus (R→L arterial level shunt)

13. Transitional Circulation
• With first few breaths lungs expand and serve
as the oxygenator (and the placenta is
removed from the circuit)
• Foramen ovale functionally closes
• Ductus arteriosus usually closes within first 1-
2 days

14. Neonatal Circulation
• RV pumps to pulmonary circulation and LV
pumps to systemic circulation
• Pulmonary resistance (PVR) is high; so initially
RV pressure more LV pressure
• By 6 weeks pulmonary resistance drops and LV
becomes dominant

15. Normal Pediatric Circulation
• LV pressure is 4-5 x RV pressure (this is
feasible since RV pumps against lower
resistance than LV)
• RV is more compliant chamber than LV

16. • No shunts
• No pressure gradients
• Normal AV valves
• Normal semilunar
valves
•

17. Congenital heart diseases
• abnormalities of the heart or great vessels
that are present at birth

18. Prevalence
• Congenital heart disease occurs in
approximately 0.8% of live births.
Incidence is more in :-
a-Premature
b-abortions
c-still births

19. RELATIVE FREQUENCY OF MAJOR CONGENITAL HEART LESIONS
LESION % OF ALL LESIONS
Ventricular septal defect 30-35
Atrial septal defect (secundum) 6-8
Patent ductus arteriosus 6-8
Coarctation of aorta 5-7
Tetralogy of Fallot 5-7
Pulmonary valve stenosis 5-7
Aortic valve stenosis 4-7
d-Transposition of great arteries 3-5
Hypoplastic left ventricle 1-3
Hypoplastic right ventricle 1-3
Truncus arteriosus 1-2
Total anomalous pulmonary venous return 1-2
Tricuspid atresia 1-2
Single ventricle 1-2
Double-outlet right ventricle 1-2
Others 5-10

20. Etiology
• The cause of most congenital heart defects is
unknown.
• Most cases of congenital heart disease were
thought to be multifactorial and result from a
combination of genetic predisposition and
environmental stimulus.

21. Genetics causes
• Chromosomal abnormality
• Trisomy 21 :A-V canal,VSD,ASD, others.
• Trisomy 18 :VSD,ASD,others.
• Trisomy 13 :VSD,ASD,PDA,others.
• Turner syndrome (xo):Bicuspid aortic valve and
co-aorta.
• Gene defects
• DiGeorge Syndrome: VSD,conotruncal defect.
• Noonan syndrome: PS,HCM

22. Syndrome complexes
 VACTREL syndrome
Vertebral,Anorectal,Cardiac(VSD,TOF and
others),tracheal,Renal,Oesophageal and Limb
abnormalities.
 CHARGE syndrome
“Coloboma,Heart(VSD,TOF,A-V canal),
Atresia choanal,Retardation,Gential,Ear
abnormalties.
 Kartagener syndrome :Dextrocardia

23. Adverse maternal conditions (environmental)
• Maternal infections:Rubella:PDA,PS
• Maternal diseases :DM:left septal
hypertrophy
• Drugs: - phenytoin or carbamazepine:VSD
-Valproate effect-co aorta, left heart
hypoplasia
• Fetal alcohol syndrome:VSD,ASD,CO-Aorta

24. Evaluation of the Infant or Child with Congenital Heart Disease
• The initial evaluation for suspected congenital
heart disease involves a systematic approach with
three major components.
• First, congenital cardiac defects can be divided
into 2 major groups based on the presence or
absence of cyanosis, which can be determined by
physical examination aided by pulse oximetry.
• Second, these 2 groups can be further subdivided
according to whether the chest radiograph shows
evidence of increased, normal, or decreased
pulmonary vascular markings.

25. • Finally, the electrocardiogram can be used to
determine whether right, left, or biventricular
hypertrophy exists.
• The character of the heart sounds and the
presence and character of any murmurs
further narrow the differential diagnosis.
• The final diagnosis is then confirmed by
echocardiography, CT or MRI, or cardiac
catheterization

26. Diagnosis
Early diagnosis of CHD mean better results.
40% of CHD diagnosed at 1st week of life.
50-60 % diagnosed at 1st two months .
Others are usually later during routine medical
examination.
Diagnosis depend on good clinical history + good
medical examination and investigations.

27. HISTORY
• The focus of the cardiovascular history depends
on the age of the patient and is directed by the
chief complaint.
• The prenatal history may identify evidence of a
maternal infection early in pregnancy (possibly
teratogenic) or later in pregnancy (causing
myocarditis or myocardial dysfunction in infants).
• A maternal history of medication, drug, or
alcohol use or excessive smoking may contribute
to cardiac and other systemic findings.

28. • Growth is an extremely valuable sign of
cardiovascular health.
• The birth weight is an indicator of the prenatal
health of the fetus and the mother.
• Infants with congestive heart failure (CHF)
grow poorly, with weight being more
significantly affected than height and head
circumference.

29. • CHF may present with a history of fatigue or
diaphoresis with feeds or fussiness.
• Breastfeeding or formula-feeding may be difficult and
prolonged because of tachypnea and dyspnea.
• Older children with CHF may have easy fatigability,
shortness of breath on exertion, and sometimes
orthopnea.
• Exercise intolerance may be determined by asking
how well children keep up playing with their friends or
in physical education class.
• Before diagnosis of CHF, patients may have been
diagnosed with recurrent "pneumonia,"
"bronchitis," wheezing, or asthma.

30. • A history of a heart murmur is important, but many well
children have a normal or innocent heart murmur at some
time in their life.
• Other cardiac symptoms include cyanosis,
palpitations, chest pain, syncope, and near-
syncope.
• A review of systems should assess for possible systemic
diseases or congenital malformation syndromes that may
cause cardiac abnormalities .
• Current and past medication use is important.
• A history of drug use is important in older children and
adolescents.
• Family history should be reviewed for hereditary
diseases, early atherosclerotic heart disease, congenital
heart disease, sudden unexplained deaths, thrombophilia,
rheumatic fever, hypertension, and hypercholesterolemia.

31. Examination
• General Observation:
• Age:
• Growth parameter: very important in CHD.
• Colour: Pink, Pale and Blue.
• Dysmorphic features: Like Down syndrome
• Jugular veins engorgement “older children”
• Vital signs: PR,RR &BP.
• Hands and legs: Clubbing, anemia, nails, edema.
• Liver and lungs: For hepatomegaly and basal
crepitations

32. Precordium
• Inspection: Looks carefully at precordium and
chest wall for apex beat pulsations,
operation scars and deformities
• Palpation: Apex beat localization, thrill, heave.
• Auscultation: Describes heart sounds and details
of added sounds timing, grading, character,
area of maximum intensity, radiation and
change with position.

33.  Auscultation
 a-First heart sound (A-V valves closure)
“Best heard at the Lt. lower sternal border or apex”
 b-Second heart sound (semilunar valve closure)
“Best heard on the 1st and 2nd I.C.S” , normally there
is normal splitting of the 2nd heart sound ,
-Single Aortic atresia,Pulmonary Artesi
-Fixed splitting ASD,PS,Rt.B.B.B
 c-Murmurs : Systolic
Diastolic
Continous

34. LABORATORY AND IMAGING TESTS
• Pulse oximetry is a painless, inexpensive, and
valuable tool to assess oxygen saturation in a
patient with possible congenital heart disease.
• The ability to recognize cyanosis varies
depending on experience and the patient's
hemoglobin.

35. ECG (Electrocardiography )
• The ECG is a valuable, noninvasive screening tool
to assess cardiac disease.
• The 12-lead ECG provides information about the
rate, rhythm, depolarization, and repolarization
of the cardiac cells and the size and wall thickness
of the chambers.
• It should be assessed for rate, rhythm, axis, P
wave, QRS, and T wave, intervals (P-R, QRS, Q-Tc)
and voltages (left atrial, right atrial, left
ventricular, right ventricular) adjusted for the
child's age.

37. Chest Radiography
• Assessment of extracardiac structures, the shape
and size of the heart, and the size and position of
the pulmonary artery and aorta.
• Abnormalities of the thoracic skeleton,
diaphragms, lungs, or upper abdomen may be
associated with congenital heart defects.
• On a good inspiratory film, the cardiothoracic
ratio should be less than 55% in infants younger
than 1 year of age and less than 50% in older
children and adolescents.

38. In general CXR can give clue to:
• Size (Cardiomegaly) & Shape
• Oligemic lung:TOF, pulmonary atresia.
• Plethoric lung: TGA,Truncus Arteriosus.
• Dextrocardia.

40. • An enlarged heart may be due to an increased
volume load (large left-to-right shunt from a VSD)
or may be due to myocardial dysfunction (dilated
cardiomyopathy).
• The shape of the heart may suggest specific
congenital heart defects.
• "boot-shaped" heart seen with TOF;tetralogy of
Fallot,
• the "egg-on-a-string" seen withTGA dextroposed
transposition of the great arteries,
• and the "snowman" seen with TAPVR
;supracardiac total anomalous pulmonary venous
return.

41. TOF TGA TAPVR

42. Echocardiography
• Echocardiography provide diagnosis in most
CHD.

43. Classification of CHD
Cyanotic CHD
• Tetralogy of Fallot
• Tricuspid Atresia
• Truncus arteriosus
• Transposition of great
vessles
• TAPVR ;total anomalous
pulmonary venous return.
• Severe Pulmonic Stenosis
• Ebstein’s anamoly
Acyanotic CHD
• Ventricular septal defect
• Atrial septal defect
• Atrio-ventricular septal
defects
• Patent ductus arteriosus
• Aortic stenosis
• Mitral stenosis/incompetence
• Coarctation of aorta
• Tricuspid regurgitation

44. Classification
CHD with little or no cyanosis “acyanotic”
• a-With Lt. ventricular enlargement
ex.- PDA ,CO-Ao
- aortic stenosis
• b-With Rt. Ventricular enlargement
ex.-ASD ,PS,MS
• c-With both ventricular enlargement
ex.- VSD

45. CHD with cyanosis “mainly Rt to Lt. shunt”
• a-With decrease pulmonary vascularity
ex.-TOF, Tricuspid Artesia
- PS with or without VSD
• b-With increase pulmonary vascularity
ex.-TGA ,Truncus arteriosus
-TAPVR