Intravascular ultrasound, or IVUS, assists in diagnosing coronary artery disease. It creates a motion picture of the inside of your coronary arteries using high-frequency sound saves. This is performed in the cardiac cath lab, where a device called a transducer is attached to a catheter and introduced to your heart through an artery. The transducer sends sound waves to bounce off artery structures and return back to the device as echoes, creating an image on a monitor.