The ECG is one of the most commonly ordered tests in emergency medicine, but the results of the test are not always simple or straightforward. Subtle and poorly-known abnormalities are very common, and they can influence patient care. The speaker will discuss an assortment of interesting and challenging ECG cases that emergency physicians from around the world, including audience members, have sent him from their own clinical practice. We will work through these "ECGs from the Frontlines" and the audience will learn to detects some of the subtleties that are often missed.