Twelve Lead Electrocardiography: Theory and Interpretation is a revised 2nd edition of Twelve Lead Electrocardiography for ACLS Providers, originally published in 1996. Twelve Lead Electrocardiography for ACLS Providers deals solely with the analysis of the shape (morphology) of ECG waveforms in order to diagnose many conditions not related to rhythm, including ischemia, acute myocardial infarction, and enlargement of heart muscle (hypertrophy). It is aimed at students who already have a familiarity with the analysis of heart rhythms. Almost all other texts of morphologic interpretation for non-cardiologists rely heavily on memorizing electrocardiographic patterns. Memorizing is difficult, and long term retention of memorized data is low. This book is unique because it leads the reader through a set of discrete building blocks of easily understood electrophysiologic principles, and then allows the reader to deduce what the 12 lead electrocardiogram will look like under various circumstances. There are no memorizing patterns. Retention is greatly enhanced, and more importantly, the reader becomes a more competent interpreter of 12 lead electrocardiograms.