Other Acyanotic Heart Defects
In these heart defects, there's a Left-to-right shunt that forms. In instances where the pulmonary pressure becomes greater than the systemic pressure, the shunt switches to right-to-left, causing the patient to become cyanotic. This is called Eisenmenger Syndrome.
Ventricular Septal Defect (VSD)
This forms a Left-to-right shunt, leading to R-sided overload and right-sided heart failure. It's commonly associated with Down’s syndrome and Turner’s syndrome.
Eisenmenger syndrome can occur here as the pulmonary pressure increases so much that the shunt turns into a Right-to-left shunt, in which the baby will become Cyanotic.
It's often asymptomatic if small, but if it's large, it presents with:
SOB on exertion e.g. breastfeeding
Increased WOB
Poor feeding
Failure to thrive
Heart failure if heart decompensates in undetected cases
O/E - Pan-systolic murmur
N.B. For the murmur, it's similar to mitral regurgitation in which there's turbulent blood flow through the septal defect during systole.
Management:
Often closes spontaneously
Surgical repair – Transvenous catheter closure or open-heart surgery
Atrial Septal Defect (ASD)
The types of ASD are:
Patent foramen ovale (PFO)
Ostium secundum – Septum secundum fails to close
Ostium primum – Septum primum fails to close, and tends to lead to an AV valve defect
It presents the same as a VSD.
O/E - Ejection-systolic murmur with a fixed, split, second heart sound (aortic and pulmonary valves close at slightly different times)
N.B. A split heart sound occurs as blood flows from the LA → RA, therefore increasing the volume of blood the RV has to eject before the pulmonary valve can close.
Management:
Surgical repair - Transvenous catheter closure or open-heart surgery
Anticoagulation in adults
Complications:
Eisenmenger Syndrome
Stroke – Embolism passes from R to L side, and up to brain
AF
Pulmonary HTN and Right-sided HF
Aortic Coarctation
This is where there's a narrowing of the aortic arch, usually just before the DA. It's often associated with Turner’s syndrome (5%).
In neonates, a weak femoral pulse is often the only presenting feature. As the baby grows, they'll begin to present with:
Radial-radial/femoral delay
If the narrowing is before the left subclavian artery, there's radial-radial delay, but if it's after this branch, there'll be radial-femoral delay.
Poor feeding
In these patients, it's very important to check the BP in both arms to assess for that radial-radial delay.
O/E - Systolic murmur
Over time, the pt may develop LVH, HF, and an underdeveloped left arm and legs due to a reduced blood flow.
Management:
Echo for monitoring
Neonates in a critical condition are given Prostaglandins to keep the DA patent
Surgical repair