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4. Abnormalities in the ECG Measurements

Topics for study:

  1. Heart Rate
  2. PR Interval
  3. QRS Duration
  4. QT Interval
  5. QRS Axis


Heart Rate

In normal sinus rhythm, a resting heart rate of below 60 bpm is called bradycardia and a rate of above 90 bpm is called tachycardia.

PR Interval

(measured from beginning of P to beginning of QRS in the frontal plane)

QRS Duration

(duration of QRS complex in frontal plane):

QT Interval

(measured from beginning of QRS to end of T wave in the frontal plane)

Frontal Plane QRS Axis

Test your knowledge on lessons 3 and 4!