Nursing students are required to show they are proficient in setting up, managing and initial interpretation of a routine electrocardiogram (ECG). This article offers you a quick guide to help you understand what an ECG is, when you can expect to perform one, what a normal rhythm looks like and how to respond if the ECG shows abnormal rhythm. Consultant arrhythmia nurse Angela Griffiths and senior lecturer in adult nursing Michael Sampson explain what can be learned from an ECG, and describe examples of common cardiac arrhythmias.