Because cardiac arrhythmias are common and EKG testing is very lucrative for the cardiologist and primary care physician, non-electrophysiologists often need a basic understanding of electrophysiology when deciding whether to refer patients for testing. This book is a concise guide to the indications for and use of electrophysiologic testing in cardiology. The author clarifies the role of electrophysiology in the evaluation of cardiac arrhythmias and discusses advances in therapeutic electrophysiology such as transcathether ablation and new catheter fluoroscope technologies.