ABSTRACT
Four-chamber view screening of the fetal heart began in the 1980s as a way to detect congenital heart disease prenatally. However, the four-chamber view alone demonstrated only modest success at detecting major congenital heart disease and failed to reliably detect many conotruncal abnormalities, such as tetralogy of Fallot and d-transposition of the great arteries.1 The concept of an “extended” fetal echocardiogram was proposed in 1992 by Achiron et al.,2 specifically as a mechanism to increase the detection of complex outflow tract and ductal-dependent lesions. Early echocardiographic teaching recommended obtaining sagittal views of the ductal and aortic arches. While continuity of both arches may be assessed in this plane, both arches cannot be imaged simultaneously, so discordance or subtle lack of continuity may be missed.3 The ability to obtain these views is also more dependent on fetal lie and operator skill.
