It may sound risky to have electricity and your heart in such close proximity, but it's not. That's how your heart works, and an EKG machine doesn't send any electricity through your body, it merely measures the electricity already in your heart. The test isn't painful, either. The only risk of physical hurt may be when they remove the stickers holding the electrodes to your chest. There's little prep work involved -- if you're particularly hairy in places where the doctor needs to attach electrodes, you might be shaved. And you may need to adjust when you take certain medications, which is information your doctor can provide. Otherwise, all you'll need to do is show up and lie still on an examining table (one exception: If a doctor calls for a stress EKG, you may need to perform a little exercise). The test should be over in five to 10 minutes, and you'll likely have results almost instantaneously.