title: Morphology of current of injury does not predict long term active fixation ICD lead performance.
abstract: BACKGROUND
  Currents of injury (COI) have been associated with improved lead performance during perioperative measurements in pacemaker and ICD implants. Their relevance on long term lead stability remains unclear.
  
  
  METHODS
  Unipolar signals were recorded immediately after active fixation ICD lead positioning, blinded to the implanting surgeon. Signals were assigned to prespecified COI types by two independent investigators. Sensing, pacing as well as changes requiring surgical intervention were prospectively investigated for 3 months.
  
  
  RESULTS
  105 consecutive ICD lead implants were studied. All could be assigned to a particular COI with 48 type 1, 43 type 2 and 14 type 3 signals. Pacing impedance at implant was 703.8+/-151.6 Ohm with a significant COI independent drop within the first week. Sensing was 10.6mV+/- 3.7mV and pacing threshold at implant was 0.8+/-0.3mV at 0.5ms at implant. There was no significant difference between COI groups at implant and during a 3 months follow up regarding sensing, pacing nor surgical revisions.
  
  
  CONCLUSIONS
  Three distinct patterns of unipolar endocardial potentials were observed in active fixation ICD lead implant, but COI morphology did not predict lead performance after 3 months.
authors.affiliation: Baroda Heart Institute and Research Centre, Vadodara, India.
authors.forename: Hanno
authors.initials: H
authors.lastname: Oswald
authors.forename: Benjamin
authors.initials: B
authors.lastname: Husemann
authors.forename: Ajmal
authors.initials: A
authors.lastname: Gardiwal
authors.forename: Christoph
authors.initials: C
authors.lastname: Lissel
authors.forename: Maximilian A
authors.initials: MA
authors.lastname: Pichlmaier
authors.forename: Ulrich
authors.initials: U
authors.lastname: Luesebrink
authors.forename: Thorben
authors.initials: T
authors.lastname: Koenig
authors.forename: Gunnar
authors.initials: G
authors.lastname: Klein