Transesophageal echocardiography with contrast of a patent foramen ovale

The sequence of images from a transesophageal echocardiography shows the right atrium (RA) and left atrium (LA) during diastole (panel A); a flap of the atrial septum is seen covering the foramen ovale. There is opacification of the RA immediately after the injection of agitated saline (panel B). Panel C shows the contrast passing from the RA into the LA through a patent foramen ovale (PFO; dashed arrow). Panel D shows a large amount of contrast within the LA (dashed arrow).