Prenatal diagnosis of fetal transposition of the great arteries.

A 31-year-old woman was referred for fetal cardiac assessment at 30 weeks of gestation because of fetal arrhythmia and inadequate visualization of the 4-chamber heart at another hospital. Routine scanning demonstrated normal growth, no anomalies, and a normal 4-chamber view; however, the great vessels were inadequately evaluated. Detailed fetal echocardiography was then performed with sequential segmental analysis. Four-chamber view showed a heart of normal size and position, with balanced chambers, intact crux, intact ventricular septum, and normal atrioventricular connections (Figure 1). The ventriculoarterial connections were identified by clear observation of the 2 outflow tract views and ascertainment of the 2 great vessels they connect, as the aorta gives off 3 brachiocephalic vessels and the pulmonary artery trunk is short, with a bifurcation at the