TGA

Question 1

Types of TGA

Answer 1

• PA from morphologic LV, Ao from RV
  o Complete: normal AV concordance
   Situs solitus, D looping, anterior/R Ao
  o Congenitally corrected transposition: AV discordance
   Double discordance = corrects the transposition
  o Lethal if not corrected

Question 2

Pathophys

Answer 2

2 independent circulations in //
o Needs shunting at some level to survive: ASD, VSD, PDA

Question 3

Mx management

Answer 3

o Maintain DA patency → PGE2
 Improve arterial saturation + ↑ mixing at atrial level

Question 4

Palliative sx correction

Answer 4

 Balloon atrial septostomy or sx creation of ASD
* Neonates, via umbilical/femoral vein
 Partial venous return repair: Baffes = connect CVC → LA w conduit
 Pulmonary artery banding
 Systemic-pulmonary anastomosis
 Rastelli operation: TGA w large VSD and severe LVOTO
* Intraventricular repair + extracardiac shunt → complete bypass of LVOT

Question 5

Definitive sx correction

Answer 5

 Atrial switch operation: physiologic correction
* Redirection of blood at atrial level: Dacron, pericardium or atrial flaps
* Systemic venous return → MV → subpulmonary LV
* Pulmonary venous return → TV → subsystemic RV
o Morphologic RV supports systemic circulation
 Arterial switch operation:
* Arterial trunks transected → anastomosed to contralateral root
* Transposition of CAs on neoAo
* VSD closed if present
* Advantage: restoration of LV as systemic pump