Stimulants and drugs are often associated with cardiac effects. Caffeine, a therapeutic
xanthine, has been described as a sympathomimetic and has shown to have stimulatory effects
on the heart. Patients with symptomatic cardiac arrhythmias are generally informed by their
physician to stop or significantly reduce caffeine intake. However, in spite of numerous
reports that have reviewed the cardiac effects of caffeine, it remains unclear to what extent
this stimulant may be detrimental, and what subgroups of patients may be most vulnerable. The
investigators propose to evaluate the effects of caffeine in patients with previously
diagnosed cardiac arrhythmias. The results of our report will provide important new
information for physicians and patients regarding the effects of caffeine on symptomatic
cardiac arrhythmias.