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Making Waves
35
As the wave of depolarization recedes, a negative deflection is
inscribed.
The EKG finally returns to baseline once again when
depolarization is complete.
The final inscription of a depolarizing wave moving
perpendicularly to a positive electrode is therefore a
biphasic wave
.
EKG
The wave of depolarization begins to recede from the electrode, gener-
ating a negative deflection.
EKG
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The cell is fully depolarized, and the EKG once again returns to
baseline.
What would the tracing look like if the recording electrode were
placed over a region of pacemaker cells sufficient to generate a
detectable current? The tracing would show a downward, negative
deflection, since all the current is moving away from the origin
where you are recording.