heart rhythm guide
heart rhythm guide

Sinus Rhythms

Normal Sinus Rhythm


  • Heart Rate: 60 to 100 beats per minute
  • P Wave: Before each QRS, identical
  • PR Interval: 120 to 200ms
  • QRS Interval: Less then 120ms
Normal Sinus Rhythm




Sinus Arrhythmia


  • Heart Rate: 60 to 100 beats per minute
  • P Wave: Before each QRS, identical
  • PR Interval: 120 to 200ms
  • QRS Interval: Less then 120ms
Sinus Arrhythmia




Sinus Tachycardia


  • Heart Rate: Greater than 100 beats per minute
  • P Wave: Before each QRS, identical
  • PR Interval: 120 to 200ms
  • QRS Interval: Less then 120ms
Sinus Tachycardia




Sinus Bradycardia


  • Heart Rate: Less then 60 beats per minute
  • P Wave: Before each QRS, identical
  • PR Interval: 120 to 200ms
  • QRS Interval: Less then 120ms
Sinus Bradycardia




Sinus Pause


  • Heart Rate: Undetermined
  • P Wave: Before each QRS, identical, dropped beat, p to p is undisturbed
  • PR Interval: 120 to 200ms
  • QRS Interval: Less then 120ms
Sinus Pause




Sinus Arrest


  • Heart Rate: Undetermined
  • P Wave: Before each QRS, identical, dropped beat, p to p is undisturbed
  • PR Interval: 120 to 200ms
  • QRS Interval: Less then 120ms
Sinus Arrest




Next Section: Conduction Defects