Interesting ECG (2)

Saw this ECG in ER.It belongs to a lady who has underlying bronchial asthma, presented with palpitation.Took me reaaaally some times to figure it out.Irregular rhythm with variable PR interval, tachycardia...what do you think it is?*The leads are well connected for the ECG so there's no cunning magic here^^Related post:Interesting ECG (1)