Page 82 - AACN Essentials of Critical-Care Nursing Pocket Handbook, Second Edition

record normal electrical activity in the ventricles. The small arrow (1) shows
the initial direction of depolarization through the septum, followed by the di-
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(B) Cross-section of the thorax illustrating how the six precordial leads
rection of ventricular depolarization, indicated by the larger arrow (2).

Normal 12-Lead ECG Waves (A) Normal sequence of depolarization through the heart as recorded by

each of the frontal plane leads.
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