Actually, the Beck electrifier can disrupt heart normal rhythm in certain users when setup in a wrist to wrist configuration. To which I'd add, I've experienced myself as I was able to induce what felt like heart palpitations. In addition to this, I experimented with the frequencies and found that the disruption only appeared to take place up to about 8Hz in my own case, after which the effect seemed to disappear. Though I suspect this could vary for others