Two-dimensional transthoracic echocardiogram with color flow and Doppler ultrasonography.Two-dimensional transthoracic echocardiogram showing a thrombus (orange arrow) in transit lodged across the interatrial septum (thick blue arrow). One lobe is present in the right atrium, measuring 1.4 cm × 0.6 cm, and one lobe is in the left atrium, measuring more than 1 cm in length.