Topic 15: Transposition of the Great arteries Flashcards
Transposition of the Great Arteries is what?
Discordant ventricular-arterial relationship
Transposition of the great arteries (TGA) or
vessels (TGV) is a malformation in which the
two great arteries carrying blood away from the heart are transposed or reversed.
LV–>PA
RV–> Aorta
Classification of congenital heart disease – how to get to TGA?
Cyanotic–>Mixed Blood Flow –>TGA/TAPVR/Truncus Arteriosus/HLHS
TGA – when is it compatible with life?
This defect is incompatible with life unless some communication exists between the two separate circulatory systems.
TGA frequently occurs with what?
Frequently, patients with TGA have ASD’s or VSD’s
TGA kids acid base status ?
acidodic usually
Classification of congenital heart disease
if patient is Cyanotic and has decreased Pulmonary BF what do they have?
TOF or Tricuspid atresia
If kid is bicaval and less than 6 kgs what venous cannulas do you use?
12/12 Fr
Classification of congenital heart disease
if pt is acyanotic and has increased Pulmonary BF what may they have?
ASD, VSD, PDA or AVSD (AV canal)
TRANSPOSITION OF THE GREAT ARTERIES (TGA) (WITH BOTH AN VSD AND A ASD)
involve what?
higher aortic pressure
prob aortic to pulm ductal flow
- Aorta emerges from RV
- PA emerges from LV
- Hole or defect in atrial septum
- Hole or defect in ventricular septum
- PDA
TGA - Parallel circulation exists - what are their orders from Body and from lungs?
Body—->RA—->RV—->AO—->Body
Lungs—>LA—->LV—->PA—->Lungs
TGA hematologic symptoms? (6)
Poor mixing Hypoxia & Acidemia Hyperventilation Increased pulmonary flow CHF Myocardial depression
the most common cyanotic congenital heart lesion presenting in the neonate?
TGA
5 % of cases of CHD
More common in males, with a ratio of about 3:1
TGA epidemiology – maternal increased risk factors?
Maternal factors associated with an increased risk include rubella or other viral illness during
pregnancy, alcoholism, maternal age over 40 and diabetes
TGA embryology? what is the defect caused by?
Bulbus cordis defect
After outflow tract septation development
begins then:
Improper spiraling of the aorticopulmonary septum
Leads to congenital disruption in pulmonary
and systemic circulations (sounds a bit like the TOF defect development)
how to tell the difference between a picture of D and L TGA?
look at the sizes of the ventricles?
anterior and to the right is which TGA defectt?
D-TGA
anterior and to the left is which TGA?
L-TGA
Outflow tract septation? TA and CC becomes what?
Partitioning of the outflow tract
Truncus Arteriosus –Aorta
Conus Cordis–Pulmonary Artery
Created by a septum that forms in the outflow tract from these swellings
Outflow tract septation is what day?
29th day
As is with TAPVR, without intervention infants
with TGA what will happen?
die within their first year of life
In 60% of the patients, the aorta is anterior and to the right of the pulmonary artery called what?
(dextro-transposition of the great arteries [d-TGA]).
levo-transposition of the great arteries [l-TGA].
The aorta may be anterior and to the left of the pulmonary artery
arterial switch
is physically switching the arteries
FIRST OPTION for tga
atrial switch
is baffling the blood
Mustard
Senning
the ONLY distinguishing characteristic that defines TGA?
Discordant ventriculo-arterial connection
Common Presentations of TGA - 4
- Transposition of the great arteries with intact ventricular septum (TGA w/IVS)
- Transposition of the great arteries with vsd (TGA w/VSD)
- Transposition of the great arteries with VSD and left ventricular outflow tract obstruction (TGA W/VSD, LVOT obstruction)
- Transposition of the great arteries with vsd and pulmonary vascular obstructive disease.