Figure 5.

Case 3: persistent L-SVC, unroofed CS. Cardiac CT with three-dimensional reconstruction (A-C) and coronal section (D). This patient's CS (B, C) is markedly dilated when contrasted with a normal CS (A). This is the result of an atypical connection with an L-SVC (B-D) that drains venous blood from the upper body and great cardiac vein via the CS. In addition, this patient's CS appears continuous with the LA (D), indicative of an unroofed CS. This produces a direct connection between the venous system and the left heart and a right-to-left shunt. CS, Coronary sinus; LAA, left atrial appendage.