Benign Structures Mimicking Right Atrial Masses on Prenatal Ultrasound

Table 1

Reported normal anatomic variants in the right atrium.

Year of publication	Reference	Number of cases discussed	Structures noted	Imaging modality used	Morphological characteristics
1992	Mirowitz and Gutierrez [2]	20	Crista terminalis; Chiari network	Cardiac MRI	Crista terminalis: nodular muscle hypertrophy; Chiari network: Muscular ridges
2006	Bhatnagar et al [3]	29	Chiari network	Autopsy specimens	Tissue strands related to the inferior vena cava
2007	Akcay et al [4]	1	Crista terminalis	ECHO	Round, immobile mass in posterior right atrium
2010	Salustri et al [5]	1	Crista terminalis	ECHO, cardiac MRI	Smooth muscular ridge
2012	Obaji et al [6]	1	Chiari network	ECHO	Mobile structure in right atrium
2013	Islam et al [7]	1	Chiari network	ECHO	Whip-like structures extending from the inferior vena cava, moving freely in right atrium

ECHO: echocardiogram; MRI: magnetic resonance imaging.