Bob wrote:
Damage from a heart attack shows as unusual routes and directions of electrical activity as the damaged bit doesn't conduct electricity normally.
Despite having personally conveyed one of the first briefings on an A-V sequential pace-makers to UK heart specialists, I realized that although I knew about the unit's electronic logic, I knew little about the way in which the power found its way to each cell. Although I now know a little more about the way in which a cell 'communicates' through its membrane, I really would like to know more about the spread of voltages across specific parts of the muscle, and how this is shown in an ECG.
Don't worry about long posts...you'd have to exceed a tad less than 6,000 words to beat some recent offerings.