In a “normal” electrocardiogram (ECG), the transition of the QRS axis in the precordial leads occurs between leads V 3 and V 4 (i.e., there is a dominant S in V 3 and a dominant R in V 4).

The ventricular rate is regular at 60 beats per minute (bpm) with narrow QRS complexes. There are typical atrial flutter waves at slightly greater than 300 bpm producing a “sawtooth” baseline pattern ...

Not all atrial flutters demonstrate the typical "sawtooth" pattern. During the times of lesser conduction on this ECG, the flutter waves are more apparent. The atrial rate is organized at a rate of ...