Premature Junctional Complex (PJC) and Junctional Escape Beats ECG Interpretation

Part I

  • PJC’s and Junctional Escape Beats may occur for a number of different reasons i.e., diet, fatigue, stress, disease, ischemia
  • Premature complexes and Junctional Escape Beats frequently occur in bradycardic rhythms, but may occur almost any time.
  • Morphologically there is no difference between PJC’s and Escape Beats.

junctional escape beat ecg image 3

Part II

  • After reviewing the previous slide you should note that the difference is that PJC’s occur early and disrupt the underlying rhythm.
  • Junctional escape beats typically occur when a cardiac rhythm is too slow and a backup pacemaker site initiates an electrical impulse.
  • It is fairly common that a Junctional Escape Beat will occur as the first complex to terminate Sinus Arrest

PJC Rhythm ECGs

  • This early impulse causes an early cardiac complex which disrupts the underlying rhythm.
  • The locus of stimulation being different, results in a change in the morphology of the P wave (inverted if it can be seen).
  • PJC ECG’s can occur occasionally or frequently.
  • PJC’s can be observed with or without a pattern
  • The P wave with PJC’s may occur before or after the QRS complex or be buried within the QRS.

Authors and Sources

Authors and Reviewers


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