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)
The electrical impulses causing the atrial activity are moving or wandering. Observe at least three different shaped P waves. No other changes in the tracing may be observed. The rhythm may or may not be regular.
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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