Congenital Heart Disease

Question 1

What are the two types of atrial septal defect, and which is most common?

Answer 1

Ostium secondum (most common)
Ostium primum

Question 2

What are the clinical features of a small ventricular-septal defect?

Answer 2

Usually asymptomatic

Pansystolic murmur loudest at the lower left sternal edge is picked up, usually on routine childhood examination

Question 3

Which chemical keeps the ductus arteriosus open in the foetus, and where is it produced?

Answer 3

Prostaglandin E2

Produced in the ductal epithelium

Question 4

Are septal defects cyanotic or acyanotic?

Answer 4

Acyanotic - there is a left to right shunt

Question 5

What are the possible symptoms of a patent ductus arteriosus?

Answer 5

• May be none
• Apnoea
• Bradycardia
• Increased oxygen requirement
• Difficulty weaning from artificial ventilation
• Bounding pulse
• Continuous ‘machinery murmur’

Question 6

What is the management for symptomatic patent ductus arteriosus?

Answer 6

Physiological closure with prostaglandin synthetase inhibitor e.g. indomethacin or ibuprofen

Surgical ligation if medical management fails

Question 7

Which is more common, ASD or VSD?

Answer 7

VSD

Question 8

Which vessel carries oxygenated blood from the placenta to the foetus?

Answer 8

Umbilical vein

Question 9

What does the ductus venosus do?

Answer 9

Connects the umbilical vein to the inferior vena cava, allowing oxygenated blood from the placenta to bypass the liver

Question 10

Which opening in the foetal circulation connects the right atrium to the left atrium?

Answer 10

Foramen ovale

Question 11

Which opening in the foetal circulation connect the pulmonary arteries to the aorta?

Answer 11

Ductus arteriosus

Question 12

What are the heart sounds like in an atrial septal defect?

Answer 12

Wide, fixed splitting of the second heart sound (‘lub splat…lub splat…lub splat’)

Question 13

What are the heart sounds like in a patent ductus arteriosus?

Answer 13

‘Machinery murmur’ i.e. continuous murmur, loudest in the pulmonary region and radiating to the back

Question 14

What are the features of a benign murmur?

Answer 14

Soft, systolic murmur at the left sternal edge
No radiation to carotids
No bruits
May be associated with a fever, and will resolve when the fever settles

Question 15

How might a child with a large ventricular septal defect present?

Answer 15

Signs of heart failure at 4-6 weeks
Breathlessness / sweating whilst feeding or crying
Recurrent chest infections
Faltering growth

Question 16

What are the clinical SIGNS of a large VSD?

Answer 16

Pan systolic murmur may be absent or soft due to the large size of the defect

Question 17

What is Eisenmenger’s phenomenon?

Answer 17

Reversal of a left to right shunt e.g. in patient with a VSD where the blood is being forced from left to right out of the pulmonary arteries, the continued force will eventually cause the pulmonary artery to become stenosed and thus increase it’s resistance. Because blood moves via the route of least resistance, the shunt will reverse and blood will go from right to left out of the aorta. As the blood is deoxygenated, this causes cyanosis.

Question 18

How might an atrial septal defect present?

Answer 18

Asymptomatic until an arrhythmia in the patient’s 30s or 40s (e.g. SVT and AF). Heart sounds: ‘wide, fixed, splitting of the 2nd heart sound’

Question 19

What are the components of Tetralogy of Fallot?

Answer 19

Pulmonary stenosis
Right ventricular hypertrophy
Overriding aorta
VSD
(Also remember 'ejection systolic murmur')

Question 20

What is the treatment for Tetralogy of Fallot?

Answer 20

Blalock-Taussig Shunt - performed between 1 and 5 years of age

Question 21

What signs might you get on cardiovascular examination of an infant and a child with coarctation of the aorta?

Answer 21

Both = Systolic murmur
Infants = Absent femoral pulses
Older children = Radio-femoral delay

Question 22

Which type of shunt is cyanotic - a right-to-left, or a left-to-right?

Answer 22

Right to left shunts are cyanotic

Question 23

Give 2 examples of cyanotic congenital heart defects

Answer 23

Tetralogy of Fallot

Transposition of the Great Arteries

Question 24

What is the arrangement of arteries in transposition of the great arteries?

Answer 24

The aorta comes off the right ventricle, the pulmonary arteries come off the left ventricle

Question 25

What is the presentation of transposition of the great arteries?

Answer 25

Cyanosis, especially from Day 2 of life when the ductus arteriosus has closed

Question 26

Explain the defect in transposition of the great arteries

Answer 26

The great arteries are switched around, such that the aorta comes off the right ventricle and the pulmonary arteries come off the left ventricle. This means deoxygenated blood is carried round the body, and oxygenated blood is transported to the lungs. This is not compatible with life unless there is a shunt which allows mixing of the 2 circulations e.g. a VSD or ASD. It presents with cyanosis, especially after the ductus arteriosus closes because this maintains mixing of blood until that point.

Question 27

What is the treatment for transposition of the great arteries?

Answer 27

Prostaglandin infusion to keep the ductus arteriosus open
Septostomy creates a shunt between the atria to maintain mixing of blood
Arterial ‘switching’ operation

Question 28

If an ASD is detected in childhood, should it be corrected?

Answer 28

Yes - It should be corrected before significant pulmonary hypertension and need for lung transplantation occurs