ABSTRACT
Sinus arrhythmia is normal in children. It is abnormal in adults but not
indicative of specific pathology. The heart accelerates during inspira-
tion and slows during expiration (ECG 90).
Wandering pacemaker
Wandering pacemaker is seen usually with sinus arrhythmia, with the
same clinical significance. The sinus pacemaker may move location
within the SA node from beat to beat. This shows up as a change in
P wave size and PR interval.