title: Generator pocket adhesions of cardiac leads: classification and correlation with transvenous lead extraction results.
abstract: OBJECTIVE
  Pacemaker (PM) and implantable cardioverter defibrillator (ICD) leads become encapsulated intravascularly and in the generator pocket by fibrotic adhesions that accumulate over time. These adhesions are responsible for the difficulty and risk of lead extraction procedures. We developed a classification scheme for pocket adhesions, classified all of the patients in the cohort, and examined the relationship between pocket adhesions and the outcome of the procedure.
  
  
  METHODS
  The classification of adhesions with respect to the intraoperative adhesion coverage was as followed: class 0 = adhesion free; class 1 ≤ 30% of adhesion coverage; class 2 = 30-60% of adhesion coverage; and class 3 ≥ 60% coverage. Patient data between December 2010 and March 2012 were collected. A total of 100 leads were extracted from 58 patients (1.7 ± 0.8 leads/patient); the mean lead implant duration was 78.5 ± 66.7 months, and the percentage of PM/ICD leads was 68% (n = 68)/32% (n = 32).
  
  
  RESULTS
  Distribution of the leads among classes: 0 = 10; 1 = 17; 2 = 25; and 3 = 48. Average implant times (months) according to the adhesion classes: 0 = 1.2 ± 0.4; 1 = 19.8 ± 19.2; 2 = 79.3 ± 46.6; and 3 = 115.1 ± 106.0 (correlation-coefficient 0.71; P ≤ 0.05). Average numbers of extraction tools used according to the adhesions: 0 = none; 1 = 0.4 ± 0.7; 2 = 1.6 ± 1.0; and 3 = 2.3 ± 1.2 (correlation coefficient = 0.67; P ≤ 0.05). Complete removal was achieved in 100% of the patients in classes 0 and 1; 96% in class 2 (n = 24); and 75% in class 3 (n = 36) (P ≤ 0.05). Mortality = 0.
  
  
  CONCLUSIONS
  Extensive adhesions in the generator pocket predict the need for a higher number of extraction tools. High-grade pocket adhesions predict lower success rates with regard to complete lead extraction. Both findings suggest that the degree of pocket adhesions predicts the degree of intravascular adhesions.
authors.affiliation: Clinic of Cardiac and Vascular Surgery.
authors.forename: Hector Rodriguez Cetina
authors.initials: HR
authors.lastname: Biefer
authors.forename: David
authors.initials: D
authors.lastname: Hürlimann
authors.forename: Jürg
authors.initials: J
authors.lastname: Grünenfelder
authors.forename: Sacha P
authors.initials: SP
authors.lastname: Salzberg
authors.forename: Jan
authors.initials: J
authors.lastname: Steffel
authors.forename: Volkmar
authors.initials: V
authors.lastname: Falk
authors.forename: Christoph T
authors.initials: CT
authors.lastname: Starck
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D020878:Device Removal; D004567:Electrodes, Implanted / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial / Q000009:adverse effects*; D012189:Retrospective Studies; D012720:Severity of Illness Index; D000267:Tissue Adhesions / Q000145:classification / Q000175:diagnosis* / Q000209:etiology*
keywords: classification; defibrillation - ICD; lead extraction; pacing; surgery