Pacemakers

Indications

• Sinus node dysfunction
  • Any symptomatic pauses, regardless of length
  • AV block
  • Second degree heart block, if high grade or symptomatic
  • Third degree/complete heart block
  • NOT for reversible causes
• RCA infarction
• Large anterior MI
• Drugs
• Endocarditis with AV involvement
• Post-TAVI
• Other

Classification

• Paced-sensed-response
• Pacing: atria or ventricle
• Sensed: atria or ventricle
• Response function
  • I: inhibit the PPM if the intrinsic rate is high enough
  • D: inhibit pacing and look for rhythm
  • Rate response: changes the paced rate depending on movement (with an accelerometer) or respiratory rate (impedence)

Magnet

• PPM: Changes a pacemaker to VOO (that is, purely ventricular pacing)
• ICD: turns off an ICD's shock function

Complications

Acute

• Pneumothorax (so do a CXR 4h after insertion)
• Perforation or tamponade
• Hematoma
• Lead dislodgement

Chronic

• Erosion
• Infection
• Chronic pain
• Twiddler's syndrome (chronic fiddling with the pulse generator causing dysfunction)
• Subclavian crush syndrome (lead entrapment between the subclavian vein and the first rib)