ABSTRACT
For a multicellular organism to function there must be communication between the cells. The more complex the organism, the greater is the need for specialized tissue to mediate this communication. The communication of electrical information is achieved through the propagation of impulses along the cell membrane of excitable cells. Cardiac electrophysiologists are generally interested in understanding the underlying mechanisms of excitability of cardiac muscle under both normal and abnormal conditions and how the cell-to-cell communication can be affected or modulated through some external means. For example, coronary artery disease may result in ischemia in which regions of myocytes may be transiently or permanently deprived of oxygen or nutrients, degrading both the excitability (the ability to create impulses) and the cellular coupling (the ability for current to flow from cell to cell). Effective treatments of such a condition need be considerate of the consequences of ischemia on both the membrane and the tissue structure.
