You can see clear AV dissociation, it's heart block. Atrial rate is around 100, ventricular rate around 40 or something. Take a piece of paper of calibers and mark out p waves, and if they happen to fall on a QRS or a T wave, then they are buried and the T wave should look different then the rest. If it's hard to see in the rhythm strip, scan the rest of the leads for clear p waves.