title: Risk factors for implantable defibrillator lead fracture in a recalled and a nonrecalled lead.
abstract: BACKGROUND
  The Medtronic Sprint Fidelis implantable cardioverter defibrillator (ICD) lead was "recalled" in October 2007 after 268,000 implants worldwide due to increased failure risk. Manufacturer suggested monitoring has not been shown effective at preventing adverse events. Only limited data exist regarding clinical predictors of Fidelis lead fracture. We sought to identify risk factors for Fidelis fracture to guide clinical monitoring and compare its performance with a control lead.
  
  
  METHODS
  Fractured lead cases were retrospectively reviewed for demographic data, implant technique, radiographic appearance and clinical presentation was analyzed. Lead survival was compared using Kaplan-Meir curves.
  
  
  RESULTS
  Study patients (n = 1314) experienced 18 Fidelis and 6 Quattro lead fractures. Patients with failed Fidelis leads were younger than those with surviving leads (49.5 vs 64.6 years, P = 0.0066). Fidelis lead fractures often occurred around the time of physical activity. No other measured demographic or technique related factors were associated with lead fracture. Fidelis leads had significantly decreased survival compared with Quattro leads (89.3 vs 98.9% at 30 months). Patients less than 50 years old had significantly decreased lead survival compared with those older than 50 in both Fidelis (79.6% vs 96.5% at 24 months) and Quattro (93.4 vs 99.8%, P < 0.001 at 24 months) leads.
  
  
  CONCLUSIONS
  Patients under age 50, with either Fidelis or Quattro ICD leads, are at increased risk of lead fracture compared with patients over 50, particularly around the time of intense physical activity. Aggressive monitoring and advisory programming appears warranted in patients with Fidelis leads as well as especially in younger patients.
authors.affiliation: Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA.
authors.forename: T Ben
authors.initials: TB
authors.lastname: Morrison
authors.forename: Robert F
authors.initials: RF
authors.lastname: Rea
authors.forename: David O
authors.initials: DO
authors.lastname: Hodge
authors.forename: Daniel
authors.initials: D
authors.lastname: Crusan
authors.forename: Celeste
authors.initials: C
authors.lastname: Koestler
authors.forename: Samuel J
authors.initials: SJ
authors.lastname: Asirvatham
authors.forename: David
authors.initials: D
authors.lastname: Bradley
authors.forename: Win K
authors.initials: WK
authors.lastname: Shen
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Munger
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Hammill
authors.forename: Paul A
authors.initials: PA
authors.lastname: Friedman
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D003627:Data Interpretation, Statistical; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D004562:Electrocardiography; D004566:Electrodes; D004868:Equipment Failure; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013177:Sports; D016019:Survival Analysis; D055815:Young Adult