PATH - Congenital Heart Diseases - R-to-L Shunts

Question 1

RIGHT-TO-LEFT SHuNTS

Answer 1

Early cyanosis—“blue babies.”

Often diagnosed prenatally or become evident immediately
after birth.

Usually require urgent surgical
treatment and/or maintenance of a PDA.

The 5 Ts:

1. Truncus arteriosus (1 vessel)
2. Transposition (2 switched vessels)
3. Tricuspid atresia (3 = Tri)
4. Tetralogy of Fallot (4 = Tetra)
5. TAPVR (5 letters in the name)

Question 2

Persistent truncus arteriosus

Answer 2

Truncus arteriosus fails to divide into pulmonary trunk and aorta due to lack of *aorticopulmonary septum formation

*only one outlet but divided into pull trunk and aorta–>ox and deox blood enters both

most patients have accompanying VSD

Question 3

D-transposition of great vessels

Answer 3

Aorta leaves RV (anterior) and pulmonary trunk leaves LV (posterior)

Due to failure of the *aorticopulmonary septum to spiral

Not compatible with life unless a shunt is present
Without surgical intervention, most infants die within the first few months of life

Question 4

Tricuspid atresia

Answer 4

Absence of tricuspid valve and hypo plastic RV

requires both ASD and VSD for viability

Question 5

Tetralogy of Fallot

Answer 5

Most common cause of
early childhood cyanosis

Caused by anterosuperior displacement of the
*infundibular septum

PROVe
-*Pulmonary infundibular stenosis (most important determinant for prognosis)
- RVH — boot-shaped heart on CXR
Overriding aorta
VSD

*“tet spells” (often caused by crying, fever, and exercise due to exacerbation of RV outflow obstruction)

Question 6

Total anomalous pulmonary venous return (TAPVR)

Answer 6

Pulmonary veins drain into right heart circulation

associated with ASD and sometimes PDA to allow for right-to-left shunting to maintain CO

Question 7

Ebstein anomaly

Answer 7

displacement of tricuspid
valve leaflets downward into RV, artificially “atrializing” the ventricle

Associated with tricuspid regurgitation and right HF.

Can be caused by *lithium exposure in utero