Echogenic structures in the left atrioventricular groove: diagnostic pitfalls.

A variety of echogenic structures that can be detected by echocardiography in the left atrioventricular groove are best seen in the parasternal long-axis view and can be missed if not carefully looked for. Normal anatomic structures or variants can be seen, for example, dilated coronary sinus, persistent left superior vena cava, or lipomatous tissue. Degenerative or inflammatory processes of the mitral annulus (calcification of the mitral annulus, mitral annular abscess) and aneurysms of the left circumflex coronary artery or of the descending aorta can depict pathologic structures. Hiatal hernia and tumors can be found as well.