Abstract
The present case illustrates pulmonary vein isolation guided by real-time three-dimensional transesophageal echocardiography. This imaging modality allowed to navigate in a point-by-point fashion around pulmonary veins to assess both catheter location in relation to pulmonary vein ostia and stability of catheter tip. Also, it offered high-resolution visualization of a thickened, prominent tissue that surrounded the left upper pulmonary vein (the ligament of Marshall). The ability to visualize this anatomical structure along with intracardiac recording of electrical signals allowed to safely modulate in loco radiofrequency energy delivery, thus achieving electrical isolation of the pulmonary vein.