Cardiac conduction devices

Implantable cardiac conduction devices (also known as cardiac implantable electronic devices or CIEDs) are a very common medical device of the thorax, with over one million implanted in the United States of America alone.

There are two major types of cardiac conduction devices: pacemakers and automatic implantable cardioverter-defibrillators (AICD/ICD), and these may be co-implanted as an ICD-pacemaker combination. Both have two major components:

  1. pulse generator (battery pack and control unit): most commonly placed subcutaneously in the infraclavicular area
  2. lead wires with electrodes for contact with the endocardium or myocardium

Cardiac pacemakers may be temporary or permanent, with the latter commonly known by the acronym PPM (permanent pacemaker). 

Categorization depends on the number of electrodes and location of pacing:

Automatic implantable cardioverter defibrillators

AICDs are common cardiac devices designed for both patient monitoring and therapy in case of ventricular tachycardia or fibrillation. AICDs consist of various combinations of sensing and shocking electrodes. They are frequently combined with a pacemaker as a bundled system for the patient, treating both the patient’s established arrhythmia and also acting as a fail-safe system should ventricular fibrillation or ventricular tachycardia occur.

Some types of AICD have leads that are implanted in the subcutaneous soft tissues (i.e. outside the thoracic cavity) 5

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Article information

rID: 12188
System: Chest, Cardiac
Section: Gamuts
Synonyms or Alternate Spellings:
  • Permanent pacemakers (PPM)
  • Cardiac pacemakers
  • Automatic implantable cardioverter defibrillators (AICD)
  • ICD-pacemaker
  • PPMs
  • ICDs
  • Cardiac implantable electronic device (CIED)
  • CIED

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Cases and figures

  • Case 1: biventricular pacemaker
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  • Case 2: dual chamber pacemaker
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  • Case 3: retained pacemaker wire
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  • Case 4: dislodged atrial lead
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  • post exchange.
    Case 5: fractured insulation of leads
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  • Case 6: temporary venous via femoral approach
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  • Case 7: dual chamber pacemaker
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  • Case 8: perforated lead
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  • Case 10: DTGA, atrial switch procedure and pacemaker
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  • Case 11: epicardial patch
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  • Expiratory
    Case 12: complicated by pneumothorax
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  • Case 13 : Medtronic chronicle lead
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  • Case 14: subcutaneous AICD
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