In 1992, clinical cardiac electrophysiology became a recognized sub-speciality of the American Board of Internal Medicine. The formal recognition of this highly specialized and technical field of medicine represents the culmination of thirty years of remarkable scientific and intellectual discovery. Beginning in the 1950s, cardiologists realized that cardiac arrhythmias were the cause of significant morbidity and the sudden death of at least 350,000 patients every year in the United States alone. At that time the only tools available for analyzing abnormal heart rhythms were the standard EKG...