Digoxin and Symptomatic Bradyarrhythmia: the 'demon' or a 'red herring'

Digoxin toxicity has been implicated in all forms of cardiac arrhythmias with the notable exception of Mobitz II atrioventricular block, which is very rare. The manifestation is quite variable, ranging from being asymptomatic to gastrointestinal, cardiac, and neurologic symptoms. The manifestations can be protean in the elderly, the most vulnerable group, where degenerative cardiac conduction system diseases add another layer of intrigue by providing an intrinsic substrate for cardiac dysrhythmia. This is in addition to age-related alteration of digoxin pharmacokinetics, use of multiple medications, chronic conditions, and electrolyte derangement, all of which increase the propensity for digoxin toxicity. We present a case of various atrioventricular conduction blocks in a septuagenarian following the use of digoxin.