May 2019

It’s all in the trends!

Holly Daw – Chief Cardiac Physiologist
Barts Hear Centre, West Smithfield, London, EC1A 7BE


A 37-year-old male with a history of congenital heart disease (CHD), specifically repaired Tetralogy of Fallot and right sided aortic arch had a dual chamber ICD implanted for non-sustained VT with syncope. Since implant approximately a year device follow was largely unremarkable except for occasional non-sustained VT episodes that were self-terminating and caused no syncope or pre-syncope. The following trends were observed on remote monitoring routine follow-up.

Figure 1
Remote monitoring trends showing activity, heart rate and lead measurement trends over the last six months


What is the most likely cause for the lead trends observed?

  • Lead integrity issue
  • Header integrity issue
  • Surgical procedure
  • Medication change