Other Cyanotic Heart Defects

Transposition of the Great Arteries

In this condition, the Aorta and Pulmonary trunks are swapped around (i.e. transposed), therefore creating 2 separate circulations that don’t mix.

It's associated with:

• VSD

• Aortic coarctation

• Pulmonary stenosis

This is incompatible with life, therefore immediate survival depends on if there’s a shunt, like a PDA/SD (Septal defect) to compensate.

Most are diagnosed at antenatal scans, but patients will present with Cyanosis at birth or within a few days once the PDA/SD closes and no longer compensates.

O/E - Loud single S2

• Normally, the aorta lies posteriorly to the pulmonary trunk. But in TGA, they lie beside each other, so the sound of the valves closing superimposes (doubles up).

The definitive management is with surgical repair of the defect, but in the interim, 2 things can be done to keep the patient alive:

• Prostaglandin - to maintain the PDA

• Balloon septostomy – inflating balloon in Foramen Ovale to create a large ASD

Truncus Arteriosus

In this defect, there's only one blood vessel that comes out of the heart instead of two. This means that blood from both sides is mixed and pumped to both the lungs and the rest of the body. Effects of this are:

• Too much blood goes to the lungs so the heart has to work harder to pump blood to the rest of the body

• There’s 1 valve below this trunk, which is usually abnormal

It's associated with a VSD.

Most are diagnosed at antenatal scans, but the patient will present with Cyanosis and respiratory distress at birth.

It's managed by surgical repair.

Total Anomalous Pulmonary Venous Return

In this condition, the pulmonary veins form a connection with the pulmonary artery, therefore causing blood to flow back into the pulmonary circulation instead of the systemic circulation.

It's associated with an ASD.

Hypoplastic Left Heart Syndrome

In condition, there is Hypoplasia of the LV, Aortic valve (AS), Mitral valve (MS), and ascending aorta. Oxygenated blood from the pulmonary veins is shunted from the left to the right through an ASD, and the RV pumps this blood through the pulmonary arteries and ductus arteriosus into the descending aorta.