Cardiac mapping technologies

In general, the technologies and methodologies for cardiac electrical mapping entail registration of the electrical activation sequences of the heart, by recording extracellular electrograms. The initial uses of cardiac mapping were primarily to better understand the normal electrical excitations of the heart. However, the focus in such mapping over time has shifted to the study of mechanisms and substrates underlying various arrhythmias; these techniques have been employed to aid in the guidance of curative surgical and/or catheter ablation procedures. More recently, the advent and continued development of high-resolution mapping technologies have considerably enhanced our understanding of rapid, complex, and/or transient arrhythmias: i.e., those that typically could not before be sufficiently characterized with more conventional methodologies. For example, the ability to visualize endocardial structures during electrophysiology procedures has greatly advanced the understanding of complex cardiac arrhythmias and their complex relationships with their underlying anatomies. In addition, such technologies provide powerful tools in the subsequent treatment of cardiac patients, particularly with the promise of accurately pinpointing the source of arrhythmias and thereby providing possible curative treatments. This chapter will summarize the most recent developments in catheter navigation and three-dimensional arrhythmia mapping technologies, including both intracardiac and noninvasive approaches.