Paediatric Cardiology

Question 1

Give 4 predisposing features for Tetralogy of Fallot

Answer 1

Male
1st degree FHx of chronic heart disease
Teratogen exposure (alcohol, warfarin, trimethadione)
Genetics- CHARGE syndrome, DiGeorge Syndrome, VACTERL association

Question 2

What are the 4 features of Tetralogy of Fallot?

Answer 2

VSD
Pulmonary stenosis
Right ventricle hypertrophy
Overriding aorta

Question 3

Describe the pathophysiology of Tetralogy of Fallot

Answer 3

Significant VSD involving both the membranous and muscular septum (perimembranous VSD). The VSD is significant and causes the systolic pressures to equalise. In severe disease, increased right heart pressure reverses the shunt so blood flows from right to left= cyanotic

As blood from both ventricles flows into the aorta, the aorta becomes dilated and is displaced over the interventricular septum.

The right ventricular outflow tract is narrow and stiff so there is impaired flow of deoxygenated blood into the pulmonary artery. This can cause intermittent RVOT obstruction which leads to cyanotic spells.

In response to the high pressures needed to overcome the RVOT right ventricular hypertrophy develops.

Question 4

What symptoms can be experienced in Tetralogy of Fallot?

Answer 4

Cyanosis
Respiratory distress
Recurrent chest infections 
Failure to thrive
Tet spells --> paroxysm of hyperpnoea (rapid deep breathing), irritability, increasing cyanosis
Anaemia
Dehydration

Question 5

What signs on examination might be found in a patient with Tetralogy of Fallot?

Answer 5

General –> Central cyanosis, Clubbing
Palpation –> Thrill or heave
Auscultation –> Loud, single S2, pancystolic murmur, ejection click, continuous machinery murmur

Question 6

Give 4 signs of congestive heart failure

Answer 6

Sweating 
Pallor
Tachycardia
Oedema
Hepatosplenomegaly 
Bibasal crackles 
Gallop rhythm

Question 7

What investigations can be done to diagnose Tetralogy of Fallot?

Answer 7

Echo (Gold Standard) 
ECG
CT angiogram 
Cardiac MRI
Cardiac catheter
Microarray
Chest x-ray - boot shaped heart

Question 8

How is Tetralogy of Fallot managed medically?

Answer 8

Squatting position- increases venous return
Prostaglandin infusion- maintains PDA
Beta blockers- reduces HR, increases venous return
Morphine-