Anatomic variants mimicking pathology on echocardiography: differential diagnosis

Abstract

Differentiation of normal from abnormal findings is critical in echocardiography. Anatomic variants occurring in normal cardiac developments often simulate pathologic entities. This review focuses on the differential diagnosis of normal anatomic structures from pathologic ones in echocardiography.

Keywords: Anatomic variation; Echocardiography.

Fig. 1

Eustachian valve. Note the leaf-like linear structure (arrowhead) at the junction of IVC RA in four chambers (A), right ventricular inflow (B) and bicaval view of transesophageal echocardiography (C). Ao: ascending aorta, IAS: interatrial septum, IVC: inferior vena cava, LA: left atrium, LV: left ventricle, RA: right atrium, RV: right ventricle.

Fig. 2

Prominent Eustachian valve (arrowhead) making an apparent cor triatriatum dexter. LA: left atrium, LV: left ventricle, RA: right atrium, RV: right ventricle.

Fig. 3

A: Chiari network (arrowheads) is the delicate freely mobile membranous structure in the RA. B: RV inflow view shows its close relationship with IVC. IVC: inferior vena cava, LA: left atrium, LV: left ventricle, RA: right atrium, RV: right ventricle.

Fig. 4

Crista terminalis (arrowhead) appears as the mass arising from the posterior wall of RA in four chamber view (A), but it is well visualized as muscular ridge near SVC in transesophageal echocardiography (B). EV: Eustachian valve, IVC: inferior vena cava, LA: left atrium, LV: left ventricle, RA: right atrium, RV: right ventricle, SVC: superior vena cava.

Fig. 5

A: Thrombi of RA (arrowheads) in parasternal short axis view. B: Computed tomography imaging of the same patient. Ao: ascending aorta, LA: left atrium, LV: left ventricle, RA: right atrium, RV: right ventricle.

Fig. 6

Normal variants of RV. A: Moderator band (arrowhead). B: Prominent papillary muscle. C: Hypertrabeculation (asterisk). IVS: interventricular septum, LA: left atrium, LV: left ventricle, RA: right atrium, RV: right ventricle.

Fig. 7

Pathologic lesions involving RV. A: Thrombus (arrowheads) attached to chordae tendineae and the wall of RV with significant dilation and impaired contractility. B: Irregular thickening of RV free wall (arrowheads) due to metastatic lung cancer. Note the pericardial effusion around the RV. LA: left atrium, LV: left ventricle, RA: right atrium, RV: right ventricle.

Fig. 8

Normal LV variants. A: Fibrous LV band (arrowhead) pass the LV cavity with transverse direction. B: Muscular LV band (arrowhead). C: Apically located papillary muscle (arrowheads) with chordae tendineae. LA: left atrium, LV: left ventricle, RA: right atrium, RV: right ventricle.

Fig. 9

A: Atrial septal aneurysm (arrowhead) in four chamber view. B: It may show tissue drop mimicking atrial septal defect. C: The degree of excursion (a) from the atrial septal plane (b) is used to quantify the size of atrial septal aneurysm. LA: left atrium, LV: left ventricle, RA: right atrium, RV: right ventricle.

Fig. 10

Lipomatous hypertrophy of atrial septum in subxyphoid view. Marked fatty infiltration of the superior and inferior region (asterisks) of atrial septum with central sparing result dumbbell-shaped appearance. arrowhead: interatrial septum, LA: left atrium, RA: right atrium.

Fig. 11

Lambl's excrescence in parasternal long (A) and short (B) axis view. Threadlike fronds (arrowhead) on the sites of aortic valve closure are flapping along the cardiac cycle. Ao: ascending aorta, AV: aortic valve, LV: left ventricle.

Fig. 12

Papillary fibroelastoma (arrowhead) in aortic (A) and tricuspid valve (B). It appears jelly-like small nodular mass with short stalk. Ao: ascending aorta, LA: left atrium, LV: left ventricle, RA: right atrium, RV: right ventricle.

Fig. 13

A: Vegetation (arrowhead) is formed on the path of regurgitant jet. B: The inflammation and leaflet destruction with significant regurgitation are additional finding. Ao: ascending aorta, LV: left ventricle.

Fig. 14

Periaortic echo-free space. A: Transverse pericardial sinus (asterisk) is normally seen at short axis view. B: Periannular abscess (asterisk) due to infective endocarditis in a patient with prosthetic aortic valve. Ao: ascending aorta, AVR: aortic valve replacement, LA: left atrium.

Fig. 15

Pericardial echo-free space. A: Epicardial fat (asterisk) showing anterior location and granular texture. B: Pericardial effusion (asterisk) showing clear echo-free space with posterior-dominant location and freely moving heart. Ao: ascending aorta, LA: left atrium, LV: left ventricle, RV: right ventricle.