Lesson 4 of14
In Progress


Diagnostic Algorithm

  1. Determine the ventricular rate – note paper speed.
  2. Determine the atrial rate – note paper speed.
  3. Are P and QRS associated?
    • same rate
    • reasonable PR interval
    • consistent PR interval
  4. Determine PR interval – note paper speed
    • does it vary?
  5. Are there any P waves that are not followed by a QRS complex?
  6. Are there any QRS complexes with no P waves?
  7. Determine the width of the QRS complexes – note paper speed.
  8. Is the rhythm regular or irregular?
  9. Any premature beats? – note morphology and duration
  10. Are the P waves positive in lead II?
  11. Are the QRS complexes of normal morphology?

The critical feature with most dysrhythmias is to identify P waves (if present), note if the atrial rate is equal to, less than, or greater than the ventricular rate, and note if there is any relationship between the P waves and the QRS complexes.