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ECG & EKG
{
Julie, Kiley, Megan
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Also called EKG or ECG
Electrical events of the heart travel through
body
ECG will reveal abnormal patterns of impulse
conduction
The appearance will differ due to the
placement of monitoring electrodes
The Electrocardiogram
Appearance
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Analyzing an ECG involves measuring the size of
the voltage changes and determining the temporal
relationships of the various components
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P wave- accompanies the depolarization of the atria
QRS complex- appears as the ventricles depolarize.
This signal is relatively strong because of the mass of
the ventricular muscle
An increase in heart size would increase the size of
the complex
T wave- indicates the ventricular repolarization
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Times between waves are reported as segments
and intervals
Segments extend from the end of one wave to
the start of another
Intervals always include at least one entire
wave
Waves and Segments
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P-R interval- extends from the start of atrial
depolarization to the start of the QRS complex.
Extension of the P-R interval to more than 200
msec can indicate damage to the AV node
Q-T interval- indicates the time required for the
ventricles to undergo a single cycle of
depolarization and repolarization
A congenital heart defect can cause sudden
death without warning may be detectible as a
prolonged Q-T interval
Waves and Segments 2.0