ASD

Question 1

What are similarities between ASD secondum and primum?

Answer 1

1. Atrial septal defects
2. Clinically- Many are asymptomatic.
3. Heart sounds- Widely split and fixed S2 + G3 ESM in older infants and children. Mid diastolic rumble from relative TS at LLSE
4. CXR- Cardiomegaly and pulmonary plethora
   Classic findings aren’t present until shunt is large

Question 2

What is the difference between Ostium secondum and primum ASD?

Answer 2

1. Location- Sc is at the fossa ovalis, Pm septum primum
2. Frequency- Sc 50-70%, Pm 30%
3. ECG- Primum has LAD or superior axis, Sc RAD (+ iRBBB & RVH)
4. Associations- Sc Holt- Oram syndrome, Pm Downs and Ellis-van Crevald
5. Mx- Small Sc close spontaneously, Pm needs surgical repair