Wandering Atrial Pacemaker | Reference Guide.

EKG Features

Rate: Normal (60-100 bpm)
Rhythm: May be irregular
P Wave: Changing shape and size from beat to beat (at least three different forms)
PR Interval: Variable
QRS: Normal (0.06-0.10 sec)

Wandering atrial pacemaker is an arrhythmia originating in shifting pacemaker sites from the SA node to the atria and back to the SA node. On an ECG, the p-waves reflect the pacemaker shifts by shape variations. The PRI interval may vary from one beat to the next.
External Source: http://jan.ucc.nau.edu/~daa/heartlung/lectures/ekg3.html
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