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Curriculum · Pediatric / Nutrition & Growth / EPI / Routine Child Examination

Transposition of the great arteries

What it is

In transposition of the great arteries the aorta is connected to the right ventricle and the pulmonary artery is connected to the left ventricle. It is the most common cyanotic lesion to present in the newborn period, and it is duct dependent: mixing happens through a PDA, an ASD or a VSD.

How it presents

It is usually detected prenatally on US. Otherwise cyanosis is direct, or comes on day 2 of life when ductal closure leads to a marked reduction in mixing of the desaturated and saturated blood. A single S2 is typically present. Children with transposition and a large VSD have improved intracardiac mixing and less cyanosis, and may instead present with signs of heart failure.