In most of the leads, the tracing looks like ventricular fibrillation. QRS complexes are seen very well in lead I where the artefacts are not obvious. Close scrutiny also shows the QRS complexes in leads aVR and aVL (blue arrows). Artefacts are seen in between the QRS complexes in these leads. In other leads, it is difficult to make out the QRS complexes. Though interpreting this ECG may be sometimes difficult, in the clinical setting there will be no difficulty as the person will not be in cardiac arrest. Such artefacts seen on the monitor can lead to inadvertent defibrillation.