ABSTRACT
Introduction Although cardiac arrhythmias are a major source o f morbidity and mortality, our pathogenic understanding o f these disorders is poor. This is particularly true for the most serious cardiac arrhythmias, ventricular arrhythmias. Strati fication and treatment o f these most severe cardiac arrhythmias have also been challenging. One o f the mainstays o f diagnosis and therapy has been the use o f invasive electrophysiological testing coupled with pharmacological inter vention. These tests, however, are time-consuming and expensive, and have met with only modest therapeutic success. These procedures have also done relatively little to improve our understanding o f the disease and, most im portantly, are postsymptomatic. As a result, treatment has been moving toward nonspecific, invasive, and expensive implantable automatic defibrilla tors. The strength o f this approach is that it works in most circumstances; the weakness is that it is merely palliative.
