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28 Cards in this Set

  • Front
  • Back
The P Wave location, amplitude, duration, configuration, deflection
Location:Precedes QRS
Amplitude: 2-3 mm high
Duration: 0.06-0.12
Config/Deflect: rounded & upright, positive
The P Wave Signigicance
Represents atrial depolarization
When normal, assume impulse originated in the SA node (sinus rythym)
Abnormal P Waves

Peaked, notched, or enlarged
May represent atrial hypertrophy or enlargement associated with COPD , pulmonary emboli, valvular diseae, or heart failure.
Abnormal P Waves

Inverted P Waves
May signify retrograde or reverse conduction from the AV junction toward the atria.
Abnormal P Waves

Varying P Waves
The impulse may be coming from different sites, as with a wandering pacemaker, irritable atrial tissue, or damage near the SA node
Abnormal P Waves

Absent P Waves
May signify conduction by a route other than the SA node, as with a junctional or atrial fibrillation rhythm
PR Interval
Location, Duration
Location-from the beginning of the P wave to the beginning of the QRS complex
Duration-0.12-0.20 sec
PR Interval Representation
Tracks the atrial impulse from the atria thru the AV node, bundle of His, and right and left bundle branches. Key is its duration
Abnormal PRI

Less than 0.12 sec
Indicate that the impulse originated somewhere other than the SA node. Associated with junctional arrhythmias and preexcitation syndromes.
Abnormal PRI

Greater than 0.20 seconds
May represent a conduction delay thru the atria or AV junction due to digoxin toxicity or heart block-slowing related to ischemia or conduction tissue disease
QRS Complex Representation
Follows the P wave and represents depolarization of the ventricles
QRS Location, Amplitude, Duration,
Location-follows the PRI
Amplitude-5-30 mm but differs for each lead
Duration-0.06-0.12 sec (measured from the beginning of the Q wave to the end of the S wave or from the beginning of the R wave if the Q wave is absent)
Abnormal QRS

Deep wide Q waves may represent MI
Notched R waves may signify a BBB
Widened QRS may signify a ventricular conduction delay
Missing QRS may indicate an AV block or ventricualr standstill
ST Segment Representation
Represents the end of ventricular conduction or depolarization and the beginning of ventricular recovery or repolarization.
Monitoring can help detect ischemia or injury before infarction develops.
ST Segment Location and Deflection
Location-extends from the S wave to the beginning of the T wave
Deflection-Usually isoelectric-may vary from -0.5-1 mm
Abnormal ST Segment

0.5mm or more below baseline
May indicate myocardial ischemia or digoxin toxicity
Abnormal ST Segment

1mm or more above baseline
May indicate myocardial injury
T Wave Representation
Represents ventricular recovery or repolarization
Also represents the relative refractory period
T Wave Location and Configuration
Location-follows the S wave
Configuration-typically round and smooth
Abnormal T waves

Bumpy T's
Because T's represent the relative refractory period, bumps may indicate that a P wave is hidden in it
Abnormal T Waves

Tall, Peaked, Tented
Myocardial injury OR
Abnormal T Waves

May represent myocardial ischemia
Abnormal T Waves

Heavily notched or pointed
In an adult, may represent pericarditis
QT Interval Representation
Represents the time needed for ventricular depolarization-repolarization cycle
Abnormal QT

Represents a longer relative refractory period and increases the risk of a life threatening arrhythmia known as torsades de points
Also associated with Class 1 Anti-arrhythmics
Abnormal QT

May result from digoxin toxicity or hypercalcemia
U Wave Representation
Represents the recovery period of the Purkinje or ventricular conduction fibers
NOT present on every strip
Abnormal U Wave

Digoxin toxicity