foetal circulation pathologies r

Question 1

what is the ductus arteriosus

Answer 1

connection between the pulmonary trunk and aorta

allows blood to bypass the lungs

Question 2

presentation of patent ductus arteriosus

Answer 2

left subclavicular thrill
continuous 'machinery' murmur
large volume, bounding, collapsing pulse
wide pulse pressure
heaving apex beat

Question 3

risk factors for patent ductus arteriosus

Answer 3

fluid restriction
diuretics
prostaglandin inhibitors - indomethacin, ibuprofen
surgical ligation

Question 4

pathology of pulmonary valve stenosis

Answer 4

the valve is not functioning correctly

usually because of adhesions between the cusps

Question 5

presentation and management of mild pulmonary valve stenosis

Answer 5

usually asymptomatic if mild

follow up every 2-3 years

Question 6

presentation of moderate/severe pulmonary stenosis

Answer 6

dyspnoea
fatigue
ejection systolic murmur

Question 7

management of pulmonary stenosis

Answer 7

balloon valvoplasty

valve replacement

Question 8

complications of balloon valvoplasty in pulmonary stenosis

Answer 8

can result in regurgitation

Question 9

aortic valve stenosis presentation

Answer 9

asymptomatic if mild 
reduced exercise tolerance
exertional chest pain 
syncope 
ejection systolic murmur that radiates to carotids

Question 10

management of aortic valve stenosis

Answer 10

balloon valvoplasty

valve replacement

Question 11

why is balloon valvoplasty harder in aortic stenosis

Answer 11

higher pressure

Question 12

what is aortic coarctation

Answer 12

narrowing of a segment of the aorta

Question 13

where is the most common place for coarctation

Answer 13

descending arch where the ductus arteriosus enters

Question 14

presentation of aortic coarctation

Answer 14

! weak/absent femoral pulse !
radio-femoral delay is only seen in chronic coarctation
systolic murmur
sudden deterioration and collapse

Question 15

what are the effects of delayed ductus arteriosus closure on a child with aortic coarctation

Answer 15

blood flows into the pulmonary trunk
this decreases the work for the LV
when the duct closes the pressure in the LV increases and it has to work really hard to pump against the coarctation
causes decreased cardiac output and acute dilation of LV
baby becomes suddenly unwell and collapses

Question 16

investigations for aortic coarctation

Answer 16

echo
doppler
MRI

Question 17

management of aortic coarctation

Answer 17

prostaglandin E1 or E2 to open ductus arteriosus
resection with end to end anastomoses
subclavian patch repair
balloon aortoplasty

Question 18

what is transposition of the great arteries

Answer 18

aorta comes out of the right ventricle

pulmonary trunk comes out of the left ventricle

Question 19

effect of transposition of the great vessels

Answer 19

basically creates 2 closed loops - one high O2 and one no O2
pulmonary artery comes out of LV so enters systemic circulation instead of pulmonary
the blood is returned to the RA with no oxygen
the aorta comes out of the RV and travels to the lungs where it is oxygenated and returned to the LA, very oxygenated but can’t supply anything

Question 20

what defects will prevent the baby from dying in transposition of the great vessels

Answer 20

anything that can cause mixing of blood
septum defect
patent ductus arteriosus

Question 21

management of transposition of the great vessels

Answer 21

often detected antenatally
prostaglandin is given as soon as the baby is born to keep the ductus arteriosus open
baby needs surgery

Question 22

definitive procedure in transposition of the great vessels

Answer 22

switch procedure
difficult because heart is so small
risk of MI

Question 23

what is tetralogy of fallot

Answer 23

four congenital abnormalities

• VSD
• overriding aorta
• pulmonary stenosis
• right ventricular hypertrophy

Question 24

presentation of tetralogy of fallot

Answer 24

central cyanosis
ejection systolic murmur
clubbing
poor feeding/weight gain

Question 25

what is a cyanotic spell in TOF

Answer 25

when the baby has an increased need for oxygen and symptoms worsen
cyanosis
SOB
O2 sats in 40s

Question 26

initial management of tetralogy of fallot

Answer 26

prostaglandins to keep ductus arteriosus open
beta blockers
shunt between subclavian and pulmonary artery to increase blood flow through lungs

Question 27

management of TOF when child reaches 5kgs

Answer 27

surgery:
VSD is closed 
aorta is restored 
infundibulum below pulmonary valve is widened 
pulmonary valve surgically opened 
lifelong follow up