W3- clinical disorders in looping Flashcards
Differentiate between the classic theory and the Van Praagh Theory
classic theory states that there is limited or incomplete spiraling of the great arteries, while the van praagh theory suggests that its based in grown and development of the conustruncas
what arch are the Proximal mediastinal branch pulmonary arteries derived from
sixth
what are the four anatomical findings in TOF
Right ventricular outflow tract obstruction
Ventricular septal defect
Aortic override
Right ventricular hypertrophy
describe the elements that lead to right ventricular outflow obstruction
–Conal septum projects into right ventricular outflow tract, crowding the infundibulum.
–Pulmonary valve often bicuspid, commisuralfusion, thickening of leaflets and hypoplasia of annulus.
–Tethering of free edges of valve cusps to the arterial wall results in supravalvar narrowing.
–With time, progression of ventricular hypertrophy which results in furthering subpulmonic obstruction.
what is the relative change in positioning of the aorta in TOF
dextral and anterior with an underderveloped pulmonary artery
–In the normal heart, right ventricular infundibulum carries pulmonary valve anteriorly and superiorly away from other three valves.
–the infundibulum is less well developed and pulmonary valve is more posterior and inferior in relation to the aorta.
how does TOF lead to R ventricular hypertrophy
no involution of R ventricle after birth–> hypertrophy also leads to fibrotic deposition and diastolic dsyfunction
what are some environmental factors that can increase the chance of TOF
–Maternal Diabetes (three-fold increase)
–Maternal phenylketonuria
–Retinoic acids
–Trimethadione
The PT presents with TOF along with immune deficiency, absence of the thymus, neonatal hypocalcemia. What syndrome is likely the cause
DiGeorge Syndrome
The PT presents with TOF along with cholestasis, CHD, skeletal and ocular abnormalities, and dysmorphic features What syndrome is likely the cause
Alagille’sSyndrome
what 2 additional findings increase the chance of TOF being due to a genetic deletion of 2q11.2?
pulmonary stensosis
arch abnormalities
what are the clinical manifestations in TOF
cyanosis
accenuated R vent impulse aka heave
single S2
systolic murmor over pulmonary outflow tract that increases with the degree of obstruction
xray- boot shaped, narrow mediastinum,, •Concavity of the left heart border from pulmonary artery hypoplasia, Oligemia
Outline the treatment for TOF
begin on prostaglandins to keep the PDA open If stable then at 3-6 months perform a Blalock-Taussig Shunt
also:
- Patch closure of VSD
- InfundibularResection
- Transannularpatch versus valve sparing patch
- Branch pulmonary artery plasty
name some mechanisms that allow a TGA PT to survive
PFO, ASD, VSD, PDA
what findings would be present on the physical exam of a PT with TGF
blue baby not in resp distress is common for heart defect
more cyanotic if VSD is smaller
X-ray
- Egg shaped cardiac silhouette
- Narrow superior mediastinum
- Mild cardiomegaly
what is the Tx for a PT with TGA
Rashkind Procedure ( make the hole bigger) –> Balloon atrial septostomy –> immediately
Arterial Switch within the first week