This document provides an overview of congenital heart disease, including common lesions and their physiology. It discusses the fetal circulation and how defects are more tolerated in utero but often cause issues after birth as pulmonary vascular resistance decreases. Common left-to-right shunt lesions like atrial septal defects, ventricular septal defects, and patent ductus arteriosus are explained. Obstructive lesions such as coarctation of the aorta and pulmonary valve stenosis are also summarized. The document provides details on presentation, diagnosis, and treatment of these various congenital heart conditions.

1. Cardiology: Congenital heart
disease_Part I
HENOK TADELE
Associate Professor
PEDIATRICS AND CHILD HEALTH

2. Learning objectives
• Identifying the fetal to neonatal transition
and its effect on cardiovascular physiology
• Identifying the epidemiology of congenital
heart disease
• Identifying and understanding the common
left to right shunt lesions with their physiology
• Identifying and understanding the common
obstructive acyanotic heart diseases with their
physiology

3. Introduction
• The incidence is higher in stillborn, spontaneous
abortuses, and premature infants.
• Most congenital defects are well tolerated in the fetus
because of the parallel nature of the fetal circulation.
• The diagnosis is established by 1week of age in 40-50%
of patients with congenital heart disease and by
1 month of age in 50-60% of patients.
• As pulmonary vascular resistance falls in the 1st several
weeks of life, left-to-right shunting through intracardiac
defects increases and symptoms become more
apparent.

4. Fetal circulation

5. • Pulmonary vascular resistance decreases due
to:
- Increased arterial oxygen
- Thinning of the medial layer of pulmonary
arterioles
- Increased number of alveolar units and vessels.
Introduction

6. Introduction cont’d
• The cause of most congenital heart defects is
unknown
• Genetics or chromosomal abnormalities have
a role

7. Acyanotic Congenital Heart Disease : The
Left-to-Right Shunt Lesions
1. Atrial Septal
Defect(ASD)
4 major types
a. Ostium secundum
b. Ostium premium
c. Sinus venosus
d. Posterior inferior

8. ASD/Ostium Secundum Defect
• Accounts for 7% of congenital heart defects.
• Females outnumber males; 3 : 1 in incidence
• The most common form of ASD
• The size of the defect, the relative compliance of
the right and left ventricles, and the relative
vascular resistance in the pulmonary and
systemic circulations determine the degree of the
shunt.
• Asymptomatic during childhood and on exam
systolic murmur at left upper sternal border is
noted.

9. • The risk of endocarditis is extremely low.
• Pulmonary hypertension, atrial dysrhythmias,
tricuspid or mitral insufficiency, and heart
failure are late manifestations
• Intervention before school entry.
• Natural history:
– Overall spontaneous closure : 87%.
– ASD<3mm- 100% by 1 ½ years
– ASD 3-8mm- 80% by 1 ½ years
– ASD>8mm rarely closes spontaneously
ASD/Ostium Secundum Defect

10. Ventricular Septal Defect

11. • Most common cardiac malformation and
accounts for 25% of congenital heart disease.
• Four types:
A. membranous
B. Muscular
C. AV canal
D. supracristal
Ventricular Septal Defect

12. • Defects <5 mm are restrictive while >10 mm
are nonrestrictive VSDs.
Presentation
• With a small VSD, the patient is asymptomatic
with normal growth and development.
• With a moderate to large VSD, delayed growth
and development, decreased exercise
tolerance, repeated pulmonary infections, and
CHF are relatively common during infancy.
Ventricular Septal Defect

13. Ventricular Septal Defect
• With long-standing pulmonary hypertension, a history
of cyanosis and a decreased level of activity may be
present.
• Systolic thrill and murmur at LLSB.
• Diagnosed by Echocardiography
• A significant number (30-50%) of small defects close
spontaneously, most frequently during the 1st 2 year of
life.
• Small muscular VSDs are more likely to close (up to
80%) than membranous VSDs (up to 35%).
• Surgery or catheter related device closure is the option
of treatment.

14. Atrioventricular Septal Defects

15. • Also called AV canal defect or an endocardial
cushion defect(ECD)
• 2% of all congenital heart defects
• Of patients with complete ECD, about 70% are
children with Down syndrome.
• Of children with Down syndrome, about 40%
have congenital heart defects and 50% of the
defects are ECD.
• Shunt both at atrial and ventricular level.
Atrioventricular Septal Defects

16. • For patients with complete ECD, heart failure
occurs 1 to 2 months after birth and recurrent
pneumonia is common.
• Without surgical intervention, most patients
die by the age of 2 to 3 years.
• Infective endocarditis and pulmonary
hypertension are most feared complications.
• Early surgical intervention is recommended.
Atrioventricular Septal Defects

17. Patent Ductus Arteriosus(PDA)

18. Patent Ductus Arteriosus(PDA)
• Female patients with patent ductus arteriosus (PDA)
outnumber males 2 : 1.
• is also associated with maternal rubella infection
during early pregnancy
• Common in premature babies.
• Accounts for 6-8% of CHD.
• Patients are usually asymptomatic when the ductus is
small.
• A large-shunt PDA may cause a lower respiratory tract
infection, atelectasis, and CHF (accompanied by
tachypnea and poor weight gain).

19. • Bounding peripheral pulses with wide pulse
pressure are characteristic findings.
• With a small shunt, these findings do not occur.
• The classic continuous murmur is described as
being like machinery in quality.
• Spontaneous closure of the ductus after infancy is
extremely rare(except in premature babies)
• Irrespective of age, patients with PDA require
surgical or catheter closure
• Infective endarteritis, CHF , Emboli are feared
complications
Patent Ductus Arteriosus(PDA)

20. Acyanotic Congenital Heart Disease : The
Obstructive Lesions , COA

21. Coarctation of the Aorta
• May be a feature of Turner syndrome
• Accounts for 5-7 % of CHD
• COA is almost always in a juxtaductal position
(i.e., neither preductal nor postductal).
• As many as 85% of patients with COA have a
bicuspid aortic valve.
• Poor feeding, dyspnea, and poor weight gain
or signs of acute circulatory shock may
develop in the first 6 weeks of life.

22. Coarctation of the Aorta
• Older children are frequently brought to the
cardiologist's attention when they are found to
be hypertensive on routine physical examination
• The classic sign of coarctation of the aorta is a
disparity in pulsation and blood pressure in the
arms and legs
• The femoral, popliteal, posterior tibial, and
dorsalis pedis pulses are weak (or absent in up to
40% of patients), in contrast to the bounding
pulses of the arms and carotid vessels

23. Coarctation of the Aorta
• Infants with COA are pale and experience varying
degrees of respiratory distress.
• Oliguria or anuria and shock are very common.
• In symptomatic neonates, PGE1 infusion should
be started to reopen the ductus arteriosus and
establish flow to the descending aorta and the
kidneys during the first weeks of life.
• Surgical repair is a rule.

24. Pulmonary Valve Stenosis

25. Pulmonary Valve Stenosis
• Accounts for 7-10% of all congenital heart defects
• Arterial oxygen saturation will be normal even in
cases of severe stenosis
• Patients with mild or moderate stenosis usually
do not have any symptoms.
• Severe stenosis, signs of right ventricular failure
such as hepatomegaly, peripheral edema, and
exercise intolerance may be present.
• Balloon valvuloplasty is the initial treatment of
choice for the majority of patients( moderate or
severe cases)