Of the many screening tests heart patients may be advised to undergo, the stress echocardiography (echo) test may be among the more misunderstood and overused. If you have heart disease, you may have taken the test at least once. It starts with you lying on a table in your doctors office, while a transducer is held over your chest to provide ultrasound images of your heart at rest. Youre then asked to walk on a treadmill or pedal an exercise bike, with ever-increasing resistance. After several minutes, more ultrasound images are taken of your heart working during that exercise. A stress echo is effective at showing the size and shape of the heart, as well as how well the chambers and valves are functioning. The test is painless, but it can be expensive. And whats more, its often not necessary.