Pacemaker Rhythms ECG Interpretation


Introduction Part 1

  • Rhythms are often named according to the source of the electrical activity in the heart or the structure where the problem is occurring.
  • Pacemaker Rhythms are aptly named due to the locus of stimulation coming from an artificial impulse generator called a pacemaker.
  • The most common pacemakers may deliver an electrical impulse to the right atrium, right ventricle or both.
  • Artificial pacemakers are often implanted as a result of either a failure of the higher (faster) pacemakers within the heart or an irregular rhythm resulting in decreased cardiac output.
  • Remember, the fastest electricity in the heart (regardless of location or source) will dictate the heart rate.

Introduction Part 2

  • Each rhythm in this category will share unique a morphologic feature which separate them from all other rhythms.
  • Pacemaker rhythms are identified by the presence of a conspicuous vertical mark known as a “spike”.
  • If the spike precedes the P wave, it is referred to as an Atrial Pacemaker rhythm.
  • If the spike precedes the ventricular depolarization, it is referred to as a Ventricular Pacemaker rhythm.
  • If there is a spike prior to the P wave and the ventricular depolarization, it is referred to as an AV (atrioventricular sequential) Pacemaker rhythm. Note: QRS complexes in Ventricular and Atrioventricular Pacemaker rhythms will have a wide, bizarre appearance (just like ventricular rhythms) and typically measure 0.12 seconds or greater.
  • After learning the unique features just described, it is simply a matter of recalling the unique feature and associating it with the corresponding waveform.

Introduction Part 3

  • During implantation, pacemakers are programmed by the physician to provide electrical impulses at a specific strength of impulse (enough to cause depolarization) and with a certain rate to maintain cardiac output within a specific normal range.
  • Many pacemakers also are programmed to “sense” the inherent electrical activity occurring within the heart, so the device only turns on when needed and does not compete with the patients own natural electrical activity.
  • Sensing capability is an important safety feature in pacemakers to ensure the electrical impulse provided by the pacemaker does not inadvertently occur during the vulnerable period of repolarization (relative refractory period).

Introduction Part 4

  • Unfortunately not all pacemakers work the way they should. According to Pub Med, an article titled “Complications related to permanent pacemaker therapy” (http://www.ncbi.nlm.nih.gov/pubmed/10353129): In a group of patients studied at Kuopio University Hospital, inadequate capture or sensing was observed in 7.4% of the patients.
  • A variety of problems can occur when is comes to pacemakers. The wire may not embed in the endocardium or pull out post-procedure, the device may oversense or undersense or fail to capture.



Authors and Sources

Authors and Reviewers


Sources

  • Electrocardiography for Healthcare Professionals, 6th Edition Kathryn Booth and Thomas O'Brien
    ISBN10: 1265013470, ISBN13: 9781265013479
    McGraw Hill, 2023
  • Rapid Interpretation of EKG's, Sixth Edition
    Dale Dublin
    Cover Publishing Company
  • EKG Reference Guide
    EKG.Academy
  • 12 Lead EKG for Nurses: Simple Steps to Interpret Rhythms, Arrhythmias, Blocks, Hypertrophy, Infarcts, & Cardiac Drugs
    Aaron Reed
    Create Space Independent Publishing
  • Heart Sounds and Murmurs: A Practical Guide with Audio CD-ROM 3rd Edition
    Elsevier-Health Sciences Division
    Barbara A. Erickson, PhD, RN, CCRN
  • The Virtual Cardiac Patient: A Multimedia Guide to Heart Sounds, Murmurs, EKG Jonathan Keroes, David Lieberman
    Publisher: Lippincott Williams & Wilkin)
    ISBN-10: 0781784425; ISBN-13: 978-0781784429
  • Project Semilla, UCLA Emergency Medicine, EKG Training Breena R. Taira, MD, MPH
  • ECG Reference Guide
    PracticalClinicalSkills.com






An error has occurred. This application may no longer respond until reloaded. Reload 🗙