Download ECG Lecture Chapter 4

Chapter 4
Supraventricular Rythms II
Abnormal conduction
• Initiation of the heart
beat occurs in the
ventricles.
• Impulse is spread
through the myocardial
cells via gap junctions.
PVC (pg. 43)
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Early
Wide (>100 ms)
1mm = 40 ms
>2.5 boxes
• Different morphology
Uniform and “Multiform” (pg.44)
• PVCs that look different in the same ECG
lead.
• Multifocal vs. Multiform.
Compensatory Pause Vs.
Interpolated PVC (pg.44-45)
Bigeminy, Trigeminy, Quadregiminy
(pg. 46)
Couplets, Triplets, VTach (pg.46-47)
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Short, non-sustained, or self terminating (pg.47)
Sustained V-Tach (> 30 seconds)
Sustained=MI. Shock treatment, meds.
Patient may be awake or no pulse.
Torsades de pointes
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“Twisting of the Points”
Looping or shifting of the ectopic beat.
Differing appearance than VTach – not as lethal.
Cause is electrolyte abnormalities (K+) or
medication.
• Usually begins with a prolonged QT, usually is
not sustained for long periods.
R on T PVC (pg. 48)
• Why is this a big deal?
Accelerated and Escape
Ideoventricular Rythms
• Wide QRS but rate <100.
• Pacemakers above AV Node have failed.
Not PVCs. Not early beats but escape
beats. Very slow HR. Poor Q.
Ventricular Fibrillation (Pg. 50-51)
• Numerous, unorganized, chaotic, rapid
depolarizing of the ventricles.
• No Pulse, no Q.
Coarse vs. Fine
Agonal Vs. Asystole (pg. 50-51)
• Agonal – very slow rhythm that proceeds death.
Differing pacemakers.
• Asystole – The absence of electrical activity.
No pulse, no Q. Flat line.
– Be aware of leads coming off.