This tracing shows the characteristics of an atrial flutter of the right atrium with a clockwise rotation. We observe
- a monomorphic and rapid pattern of atrial activity,
- in the inferior leads II, III, aVF, a mainly positive, wide wave with a notch in the positive portion in leads II and III,
- low amplitude atrial depolarization with a notch in aVL,
- negative atrial activation in V1 and positive in V6;
The electrical pattern is slightly less specific than that of the common counterclockwise flutter with more inter-patient variability. This flutter is also isthmus-dependent and can be effectively treated by ablation. It is therefore necessary to know its electrocardiographic characteristics and to be able to make the differential diagnosis from a left flutter for example, the therapeutic actions being very different.