EKG Nomenclature ECG Interpretation #301

Normal ECG tracings consist of waveform components that indicate electrical events during one heart beat. These waveforms are labeled P, Q, R, S, T and U. The following descriptions are with respect to Lead II.

P wave is the first deflection and is normally a positive (upward) waveform. It indicates atrial depolarization. QRS complex follows the P wave. It normally begins with a downward deflection, Q; a larger upward deflection, R; and then a downward S wave. The QRS complex represents ventricular depolarization and contraction.

T wave is normally a modest upward waveform, representing ventricular repolarization. U wave indicates the recovery of the Purkinje conduction fibers. This wave component may not be observable.

ekg waveform

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? v:3 | onAr:0 | onPs:2 | tLb:0 | pv:1
uStat: False | db:0 | cc: | tar: False
| cDbLookup # 0 | pu: False | pl: System.Collections.Generic.List`1[System.String]
em: | newuser: False

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