Atrial Pacemaker Rhythm - Course # 317-5


  • This rhythm is easily identified by the conspicuous presence of a pacing spike immediately preceding the P wave.
  • Not all pacing spikes will look exactly the same. They may be below or above the isoelectric line or be partially above and below.
  • The PR interval is measured from the pacing spike to the beginning of ventricular depolarization.
pacemaker ecg image 103

Practice Strip

  • Analyze this tracing using the five steps of rhythm analysis.
  • Compare your answers with the answers on the next slide.

pacemaker ecg image 104


  • Rhythm: Regular
  • Rate: 83
  • P Wave: upright and uniform with spikes
  • PR interval: 0.16 sec
  • QRS: 0.06 sec
  • Interpretation: Atrial Pacemaker Rhythm with 100% capture
pacemaker ecg image 104b

317 Atrial Pacemaker Rhythm - Course # 317-5