Book excerpt: This volume of intracardiac tracings builds on our first book, Essential Concepts of Electrophysiology and Pacing through Case Studies, that guides the reader in developing and refining the key skill of analyzing electrophysiologic recordings. Over 60 cases with a focus on intracardiac EGMs are presented as board exam cases and questions. Tracings are framed by a question, followed by annotated tracings, and a discussion of the correct and potential answers. Cases present a full range of difficulty from simple to advanced. This book will provide a valuable review for a wide variety of professionals — physicians, associated professionals, nurses and technicians — preparing for certification and re-certification examinations in electrophysiology.