W3- clinical disorders in looping

Question 1

Differentiate between the classic theory and the Van Praagh Theory

Answer 1

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

Question 2

what arch are the Proximal mediastinal branch pulmonary arteries derived from

Answer 2

sixth

Question 3

what are the four anatomical findings in TOF

Answer 3

Right ventricular outflow tract obstruction

Ventricular septal defect

Aortic override

Right ventricular hypertrophy

Question 4

describe the elements that lead to right ventricular outflow obstruction

Answer 4

–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.

Question 5

what is the relative change in positioning of the aorta in TOF

Answer 5

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.

Question 6

how does TOF lead to R ventricular hypertrophy

Answer 6

no involution of R ventricle after birth–> hypertrophy also leads to fibrotic deposition and diastolic dsyfunction

Question 7

what are some environmental factors that can increase the chance of TOF

Answer 7

–Maternal Diabetes (three-fold increase)

–Maternal phenylketonuria

–Retinoic acids

–Trimethadione

Question 8

The PT presents with TOF along with immune deficiency, absence of the thymus, neonatal hypocalcemia. What syndrome is likely the cause

Answer 8

DiGeorge Syndrome

Question 9

The PT presents with TOF along with cholestasis, CHD, skeletal and ocular abnormalities, and dysmorphic features What syndrome is likely the cause

Answer 9

Alagille’sSyndrome

Question 10

what 2 additional findings increase the chance of TOF being due to a genetic deletion of 2q11.2?

Answer 10

pulmonary stensosis

arch abnormalities

Question 11

what are the clinical manifestations in TOF

Answer 11

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

Question 12

Outline the treatment for TOF

Answer 12

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

Question 13

name some mechanisms that allow a TGA PT to survive

Answer 13

PFO, ASD, VSD, PDA

Question 14

what findings would be present on the physical exam of a PT with TGF

Answer 14

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

Question 15

what is the Tx for a PT with TGA

Answer 15

Rashkind Procedure ( make the hole bigger) –> Balloon atrial septostomy –> immediately

Arterial Switch within the first week

Question 16

what condition would present with Concavity of the left heart border from pulmonary artery hypoplasia

Answer 16

Tetralogy of Fallot