Anatomic abnormalities of the heart and great vessels that present from birth

1. CONGENITAL HEART
DISEASES
Dr. Snehil Agrawal

2. ◦ Anatomic abnormalities of the heart and great vessels that present
from birth.

3. INTRODUCTION
Congenital heart diseases are due to the defect in embryogenesis
during 3-8 weeks of gestation during which development of CVS
begins.
Severe cardiac defects are incompatible with life leading to intra
uterine death.
And those who borne will have clinical symptoms soon after
birth or in childhood life or adult life that depends on the severity
of the defects

4. Incidence:
 Congenital heart diseases most common type of heart disease among children.
 6 – 8 per 1000 full term live births.
 Increased incidence in premature babies or stillborn babies.

5. ETIOPATHOGENESIS
Genetic:
 Chromosomal abnormalities are associated with increased incidence of
congenital heart disease.
 Eg :Trisomy 21 (Down syndrome) ,Turner syndrome.
Environmental:
 Congenital rubella infection and teratogenic substances

6. Genetic basis
 Mutations of the transcriptional factors.
 Developmental errors in mesenchymal tissue migration.
 Defects in extracellular matrix.

10. MALPOSITIONS OF THE HEART
Dextrocardia
◦ The apex of the heart points to the right side of the chest.
◦ Accompanied by situs inversus so that all other organs of the body are also transposed
◦ Heart is in normal position in relation to them.
Isolated dextrocardia
◦ Associated with major anomalies of the heart such as transposition of the atria in relation to
ventricles or transposition of the great arteries.

11. MECHANISM
Shunt:
 Is an abnormal communication between the heart chambers or
vessels that facilitate the blood to flow from right to left or left
to right depending on the pressure gradient.

12. MECHANISM
Right to left shunt
venous blood mixes with the arterial blood leading to
decreased pulmonary flow and mixing of venous
blood causing cyanosis - cyanotic congenital heart
diseases.
 In these types of shunts venous emboli can bypass
pulmonary circulation and filtration causing
paradoxical embolism.
Clinically :
 cyanosis, clubbing and polycythemia.

13. MECHANISM
Left to right shunt
 arterial blood mixes with the venous blood causing
increased pulmonary flow resulting in increased pulmonary
pressure.
 Patient develops pulmonary hypertension and right
ventricular failure.

14. MECHANISM
In the later course of the disease increased right ventricular
pressure results in reversal of the shunt causing late cyanosis and
so called as late cyanotic congenital heart disease.
Reversal of shunt in a left to right shunt is called as Eisenmenger
syndrome.
Advanced and irreparable stage of shunt reversal leads to death.

16. ATRIAL SEPTAL DEFECT (ASD)
 Atrial septal defect is a late cyanotic congenital heart disease.
 8% of all CHDs.
 It is the commonest type of CHD that is asymptomatic till adulthood.
 In ASD there is an abnormal opening in inter atrial septum, which allow blood flow between left atrium and
right atrium

18. Morphology
Morphologically three types.
 Secundum ASD: Most common type with 90% incidence. It is
due to defect near fossa ovale.
 Primum ASD: Next common type of ASD. The defect is adjacent
to AV valve.
 Sinus venosus type: Least common type and the defect is near the
superior vena cava opening.

19. Morphologic features of ASD
◦ Volume hypertrophy of the right atrium and right ventricle
◦ Enlargement & hemodynamic changes of tricuspid and pulmonary
valves
◦ Focal or diffuse endocardial hypertrophy of the right atrium and
right ventricle
◦ Volume atrophy of the left atrium & left ventricle

21. Clinical course
 Cause left to right shunt as the right atrial pressure is less than
left atrial pressure and right atrium is more distensible than left
atrium leading to pulmonary flow 3-4 times of normal.
 These patients are asymptomatic till the age of 30 years and later
develop right ventricular failure, pulmonary hypertension and
reversal of shunt and cyanosis.

22. Complications
 Right ventricular failure.
 Pulmonary hypertension.
 Paradoxical embolism.
Treatment
 Surgical correction before the irreversible pulmonary vascular changes develops.

23. VENTRICULAR SEPTAL DEFECT (VSD
 Late cyanotic congenital heart disease.
 commonest type of CHD.
 30% of all CHDs.
 In VSD there is an abnormal opening in inter ventricular septum, which allow blood flow between left
ventricle and right ventricle

25. Morphology
Morphologically three types
 Membranous VSD: Commonest type of VSD comprising 90%
of VSD. The defect is present in the membranous part of
interventricular septum.
 Infundibular VSD: The defect is present in the muscular part of
interventricular septum.
 Swiss cheese VSD: Multiple fenestrations in the muscular part
of interventricular septum

26. Morphologic features of VSD
◦ Volume hypertrophy of the right ventricle
◦ Enlargement & hemodynamic changes in the tricuspid and pulmonary valves
◦ Endocardial hypertrophy of the right ventricle
◦ Pressure hypertrophy of the right atrium
◦ Volume hypertrophy of the left atrium and left ventricle
◦ Enlargement & hemodynamic changes in the mitral and aortic valves

28. Clinical course
 Smaller defects close spontaneously and unclosed smaller defect
present late in life.
 Large defects cause significant left to right flow and present in
infancy.
 If untreated later cause right ventricular failure, pulmonary
hypertension and reversal of shunt and cyanosis and death.
Treatment
 Surgical correction if the defect is large at the age of one year.

30. PATENT DUCTUS ARTERIOSUS (PDA)
 Late cyanotic congenital heart disease
 8% of all CHDs.
 There is persistence of communication between aorta and pulmonary artery, which is normally present in the intra
uterine life -persistent ductus arteriosus.
 Persistence after 3 months is considered abnormal
 90% of PDAs are isolated type.
 10% are associated with other CHDs.
◦ Etio – unknown; continued synthesis of PGE2 after birth.
◦ “Machinery –like” murmur
◦ Asymptomatic if small
◦ Life threatening – close as early as possible

33. FALLOT’S TETRALOGY
 It is the early cyanotic congenital heart disease
 Most common type of cyanotic CHD.
 Embryologically it is due to anterosuperior displacement of
infundibular septum.

34. Four morphological features
1. VSD.
2. Subpulmonary stenosis causing obstruction of right ventricular outflow.
3. Overriding of aorta.
4. Right ventricular hypertrophy.

36. Clinical features
 Severity depends on subpulmonary stenosis.
 Mild stenosis behaves similar to VSD (left to right shunt)
without cyanosis called as “pink tetralogy” as there is no
cyanosis.
 Severe stenosis is associated with high right ventricular pressure,
right to left shunt and cyanosis called as “classical tetralogy”.
 Heart is enlarged and boot shaped.

40. TRANSPOSITION OF GREAT VESSELS (TGV)
 It is an early cyanotic congenital heart disease in which there is transposition of
pulmonary artery and aorta.
 Also called as transposition of great arteries (TGA).
 Aorta arises from right ventricle and pulmonary artery arises from left ventricle.

41.  AV connections are normal (concordant).
 This kind of defect is incompatible with postnatal life.
 TGA with VSD is seen in 35% cases, which have stable shunt.
 TGA with PDA is seen in 65% cases, which have unstable and needs immediate surgical
corrections.

44. PERSISTENT TRUNCUS
ARTERIOSUS
 Early cyanotic congenital heart disease.
 There is failure of separation of embryologic truncus arteriosus into aorta and pulmonary artery
and a single great artery receives blood from both ventricles.
 The persistent truncus is always accompanied by a membranous ventricular septal defect

46. TRICUSPID ATRESIA
 Early cyanotic congenital heart disease.
 Rare anomaly
 Complete occlusion of tricuspid valve due to an unequal division of AV canal that is associated
with large mitral valve.
 Circulation is maintained by VSD or PDA and these cases have high mortality in first weeks or
months of life.

48. COARCTATION OF AORTA
 Obstructive CHD with narrowing or constriction of aorta.
 Male to female ratio is 2:1.

49. Two types
Infantile form: Coarctation is proximal to PDA.
Adult form: Coarctation is opposite to closed PDA.
Cases with coarctation with PDA have differential cyanosis.
cases with coarctation without PDA have hypertension in upper limbs,
weak pulse and hypotension in lower limbs

52. Bicuspid aortic valve
◦ 1-2% population isolated anomaly
◦ Two cusps different size with larger cusps having median raphe due to incomplete embryologic
separation
◦ Asymptomatic at birth
◦ Predispose to progressive degenerative calcification
◦ Predispose to infective endocarditis
◦ Asso. with aortic coarctation, aneurysm, dissection
◦ May become stenotic or incompetent- aortic dilation
◦ C/F- concentric LVH,angina,syncope,heart failure