DK2985_C000 1..28 - AlSharqia Echo Club

Imaging Artifacts and Pitfalls 133(A)(B)LARALVCATHETERRVMODERATORBANDFigure 6.19 Moderator band. Mid-esophageal four-chamber view in a 62-year-old man before coronary revascularization. Dilation ofthe right ventricle (RV) facilitates visualization of the moderator band. Note the densely trabeculated aspect of the RV apex. (LA, leftatrium; LV, left ventricle; RA, right atrium).from the IVC have been described (2). The eustachianvalve is best visualized when imaging both the superiorand inferior venae cavae in longitudinal section (9). Thisimaging plane allows identification of its attachment, anteriorlyat the orifice of the IVC (Fig. 6.21). It must not beconfused with thrombi, central catheters, vegetations,tumors, or other pathologic processes.G. Chiari NetworkThe Chiari network is an embryologic remnant found in2–3% of normal hearts (6). This filamentous, fenestratedmembrane is attached along the orifice of the coronarysinus (Fig. 6.22). It appears as a highly mobile structurewithin the RA, typically displaying random motion (2,6)between two insertion points on the anterior aspect ofthe orifice of the IVC (like the eustachian valve) and thesuperior aspect of the atrial septum. As mentioned forthe eustachian valve, the Chiari network must not bemistaken for a pathologic finding such as fibrinousthrombus, or vegetations.IV. ECHO-FREE SPACESA. Persistent Left Superior Vena CavaPersistent left superior vena cava (SVC) occurs in 0.5% ofotherwise normal subjects as an isolated finding. It is morefrequent in patients with congenital heart disease with aprevalence of 3–10% in that population (6). It most commonlydrains into the coronary sinus which appears markedlydilated (2,6,9). Persistent left SVC presents as anecho-free space between the LAA and the left upperpulmonary vein (LUPV). When imaged in longitudinalsection, it appears as a vascular structure anterior to theLA and connecting to the coronary sinus (Fig. 6.23) (9).Color Doppler confirms the presence of blood flow in itslumen, differentiating it from an abscess, a cystic cavity(A)(B)FOSSAOVALISIVCLASVCRALIPOMATOUS SEPTAL HYPERTROPHYFigure 6.20 Lipomatous hypertrophy. Mid-esophageal bicaval view showing lipomatous hypertrophy of the atrial septum in a74-year-old woman. The atrial septum reaches 25 mm in thickness. Sparing of the fossa ovalis results in a typical dumbbell appearance(IVC, inferior vena cava; LA, left atrium; RA, right atrium; SVC, superior vena cava).