Systems for measuring and tracking electrophysiologic distributions

Electrocardiographic mapping has played an important role in the study and analysis of cardiac electrophysiologic phenomena. The first systems used for experimental or clinical studies were expensive, cumbersome, and limited in their ability to sample the complex electrophysiologic events associated with cardiac function and disease. New insights into the mechanisms of arrhythmias and the need for timely detection and characterization of changing cardiac states have made it essential that new tools be available to measure the spatial characteristics and dynamics of electrophysiologic events. For example, observation of the distribution and dynamics of ventricular repolarization is critical to predicting arrhythmia prone states, detecting reperfusion or reocclusion in patients undergoing post myocardial infarction therapy or angioplasty, or to accurately detect acute infarction in patients presenting with chest pain. Technology now permits affordable, flexible systems for making the critical observations. The authors present an example of such a system and its applications in this article.