Abnormal ECG?

Hi all,   Sorry to bother you, I'm not a doctor but work in Healthcare... Anyway cutting the story short our new Obs Machines come with 3 Lead ECG... So keen to practise to learn how to use the equipment we had a practise on each other... One of the ECG's I have enclosed as a weblink to the photo,   It shows a little notch I've not seen before (3 lead of person in 20's with no known cardiac history) http://i1368.photobucket.com/albums/ag165/dgurd025/Mobile%20Uploads/image_zps4434a256.jpg any idea how serious?   thanks
Source: Doc2Doc BMJ Cardiology - Category: Cardiology Authors: Source Type: forums