2. The transposition of the great arteries
is ventriculo arterial discordance, in which
the aorta arises from the morphologic right
ventricle and the pulmonary artery arises
from the morphologic left ventricle.
3.
4. Transposition of the great arteries (TGA) is
the most common cyanotic congenital heart
lesion that presents in neonates.
This lesion presents in 5-7% of all patients
with congenital heart disease.
The overall annual incidence is 20-30 per
100,000 live births.
5. Etiology for transposition of the great
arteries is unknown and is presumed to be
multifactorial.
This congenital heart defect is more common
in infants of diabetic mothers.
6. (The pulmonary and systemic circulations
function in parallel, rather than in series)
Causes
Transposition of great arteries
Oxygenated pulmonary venous blood returns to
the left atrium and left ventricle
Recirculated to the pulmonary vascular bed
via the abnormal pulmonary arterial
connection to the left ventricle.
7. Deoxygenated systemic venous blood returns
to the right atrium and right ventricle
pumped to the systemic circulation,
effectively bypassing the lungs
deficient oxygen supply to the tissues and an
excessive right and left ventricular workload
8. It is incompatible with prolonged survival
unless mixing of oxygenated and
deoxygenated blood occurs at some anatomic
level like
ASD
VSD
PDA
9. Prominent and progressive cyanosis within
the first 24 hours of life is the usual finding
in infants.
Tachypnea
Tachycardia
Diaphoresis
Failure to gain weight
10. A single or narrowly split, diminished second
heart sound
Systolic ejection murmur may be present.
12. Chest radiography
demonstrate
the classic "egg on
a string"
appearance in
approximately one
third of patients.
13. Initial treatment consists of maintaining
ductal patency with continuous intravenous
(IV) prostaglandin E1 infusion to promote
pulmonary blood flow.
Antibiotic Prophylactic Regimens for
Endocarditis.
Fluid replacement
Bicarbonate administration- Acidosis
Mechanical ventilation
14. Rastelli-type procedure-ligate the main
pulmonary artery and place an
aortopulmonary shunt during the newborn
period to restrict pulmonary blood flow.
Arterial switch procedure
18. The overall survival rate following arterial
switch operation is 90%.
The overall mortality rate following an atrial
level switch is low; however, long-term
morbidity associated with systemic (right)
ventricular dilatation and failure, systemic
atrioventricular (tricuspid) valve
regurgitation, and atrial bradyarrhythmias
and tachyarrhythmias is significant.