Each echo exam may last up to 1 hour. This time will be required to perform an ultrasound examination before and during supine (lying down) bicycle exercise. The exercise period will be approximately 10-15 minutes. The bicycle exercise will be a symptom-limited test. This means that the test will be stopped if you experience any discomfort. An ultrasound examination of your heart will be done to assess heart function. You will be asked to lie on your left side on an examination table while a technician takes pictures of your heart with a small probe that is gently pressed against your chest after applying a gel. The ultrasound data will be processed to evaluate myocardial strain, a value that may be useful in describing heart function.