Cardiac anatomy and electrophysiology

Abstract

Since its development in the early 1900s by Einthoven, the electrocardiogram (usually referred to by its acronym, ECG) has become an important tool for evaluating the heart. During the last twenty years, our understanding of the basic electrophysiology of the heart has dramatically increased, which has provided further insight into the physiologic basis of the electrocardiogram. In this first chapter basic electrophysiology and cardiac anatomy will be reviewed. Although these principles can be difficult to understand, they provide an important foundation for understanding the physiologic and pathophysiologic basis for the ECG. In this way, rather than evaluating the ECG using “pattern recognition,” the mechanisms for ECG changes can be understood and hopefully more easily remembered. Readers are encouraged to refer back to this chapter as they read about specific conditions observed in an ECG in later chapters.