Lead II

 

12-Lead

 

Interpretation Rules

  • Irregularly irregular rhythm.
  • No P waves.
  • Variable ventricular rate.
  • QRS complexes usually  < 120 ms unless pre-existing bundle branch block, accessory pathway, or rate related aberrant conduction.
  • Fibrillatory waves may be present and can be either fine (amplitude < 0.5mm) or coarse (amplitude >0.5mm).
  • Fibrillatory waves may mimic P waves leading to misdiagnosis.