There's an FDA approved Insertable Cardiac Monitor available. I think this device would be great for somebody that has intermittent arrhythmias. The device is about the size of a thumb drive, and is implanted in the upper chest similar to a pacemaker. It can monitor and provide information on arrhythmias for up to three years: http://medgadget.com/archives/2007/12/insertable_cardiac_monitors_icms_reveal_dx_and_reveal_xt.html