I am going to be having a cardiac stress test on Friday. I have been experiencing bouts of shortness of breath on exertion. I have to stop all foods and beverages that contain caffeine for 24 hours prior to the test. I am also not allowed to eat after midnight on Thursday. I will be getting an IV with a contrast called "Cardiolite. From what I know, this test will help determine the blood flow to the heart muscle when the heart is under stress and at rest. Has anyone ever had one? I am hoping that I will get some answers about how well my heart is working.