Figure 4: After three months warfarin therapy, sagittal images showing thrombi within the right upper and the left upper pulmonary veins (white arrow head). The size of thrombi was decreased (4-a). Thrombi in the right upper and the left upper pulmonary veins demonstrated the change of the shape, and the size of thrombi in LA seemed to be decreased and they looked like “lines” (4-b and 4-c). AAo: Ascending Aorta; DAo: Descending Aorta; LA: Left Atrium; LUPV: Left Upper Pulmonary Vein; LLPV: Left Lower Pulmonary Vein; RUPV: Right Upper Pulmonary Vein; RLPV: Right Lower Pulmonary Vein.