Cardiology

Question 1

Cyanotic Heart Disease

Answer 1

1. Right to left ventricular shunt (eg. TOF)
2. Right to left atrial shunt (eg. PS, PPHN)
3. Mixing (eg. single ventricle)
4. Complete transposition (eg. TGA)

Question 2

Ductal Closure

Answer 2

Trigger 1: Increased oxygen pressure

Trigger 2: Decreased circulating PGs

Effect:

• smooth muscle layer DA constricts
• occlusing of vasa vasorum causing ischaemia
• production of growth factors
• DA transforms into non-contractile ligament

Timing: functional closure after 72 hours

_**Preterm:_ no vasa vasorum

Question 3

PDA

Answer 3

complications caused by redistribution of blood flow: metabolic acidosis, ICH, NEC, pulmonary oedema, hamorrhage, CCF

predictors: 1.5mm or greater in babies <1500g and<10 days, pulsatile pattern

symptoms: RDS with deterioration d5-10, bounding pulses, active praecordium, continuous mumur, cardiomegaly, lung shadowing, pulmonary haemorrhage, apnoea

Question 4

Treatment PDA

Answer 4

types: medical or surgical intervention

evidence: poor objective evidence on long-term outcomes

1st line: treat anaemia, fluid restriction, diuretics

medications:

• indomethacin 3 doses (70% efficacy)

success factors: more successful if gestation <28/40 and < 2 weeks old

surgery: is relapse after 2nd dose indomethacin