A bubble test is sometimes done in conjunction with a heart ultrasound (also called an echocardiogram) in order to provide enhanced visualization and aid in diagnosing a heart condition. With the bubble test, a “contrast” solution made up of sterile salt water is prepared by shaking it up to create bubbles. This solution is then introduced to the body via IV line. During a normal ultrasound, the bubbles will show up just on the right side of the heart. But if the bubbles appear on the left side, this will indicate the presence of some kind of opening or defect between the two halves of the heart, which can lead to a transient ischemic attack (TIA) or stroke. This painless and safe test typically adds only minutes to the testing process for an echocardiogram.