Well, you know the machine works I guess. Surprised he didn't feel the raised heart rate though, I suppose sometimes we don't 'feel' these situations (a bit like raised blood pressure etc.).
A kick in the chest doesn't sound very pleasant. Just out of interest, when they interrogate the unit, does it output a record going back several hours etc. so they can see a pattern, or does it just kick off when say heart rate >= 100 or whatever ?