Anomalies of the Tricuspid Valve: Tetrology of Fallot (TET)

Question 1

What is the initial cause of TET?

Answer 1

1. Truncus never positioned properly over the common atrium
   (failure of the arterio-pulmonary septum to align)
   (anterior inferior displacement of the infundibular septum)
2. Atrium never separated properly

Question 2

TET is considered a failure of the ____ ____.

Answer 2

conal swellings

Question 3

TET is a ____ lesion caused by _____ PA.

Answer 3

cyanotic, atretic

Question 4

In TET, the shunting is _____, due to an increase in pressure on the ____ side.

Answer 4

bidirectional, right

Question 5

Physical findings of TET include:

Answer 5

1. Cyanosis
2. Clubbing
3. Squatting

Question 6

Cyanosis is due to:

Answer 6

poor flow to lungs due to PA atresia

Question 7

Clubbing is caused by

Answer 7

vasodilation of capillary beds, fingertips swell

Question 8

Purpose of squatting in patients with TET:

Answer 8

• pressure in abdominal cavity increases
• venous return decreases
• pressure is relieved in RV and helps toddler to breathe

Question 9

Associated lesions with TET:

Answer 9

• bicuspid PA
• right sided arch
• coronary anomalies
• R to L shunt / bidirectional shunting

Question 10

Sometimes there is no VSD shunting due to ____ ____.

Answer 10

equal pressures

Question 11

4 main characteristics of TET:

Answer 11

1. VSD
2. sub-pulmonic stenosis
3. RVH
4. Overriding Aorta

Question 12

What does overriding Aorta mean?

Answer 12

the aorta is anteriorly and inferiorly displaced, sitting close to the VSD

Question 13

In TET, deoxygnated blood is blocked from exiting the RV into the ____ ____, due to ____ ____ and is shunted through the ____ into the ____ ____.

Answer 13

PA, sub-pulmonic Stenosis, VSD, Overriding Aorta

Question 14

How does squatting help patients with TET?

Answer 14

• increasing arterial vascular resistance/ increasing afterload
• increasing volume in the LV
• blood is shunted from the LV through the VSD and up into the PA
• more blood perfuses the lungs

Question 15

Surgical repair of TET:

Answer 15

(total repair within first 6 months)

1. BT Shunt
2. ASD and VSD given
3. PDA is kept open
4. RVOT reconstructed

Question 16

Surgical complications associated with TET

Answer 16

1. Bacterial endocarditis
2. pacemaker
3. LV/RV failure
4. Ventricular arrhythmias
5. growth retardation
6. death