title: Safety and efficacy of transvenous high-voltage implantable cardioverter-defibrillator leads in high-risk hypertrophic cardiomyopathy patients.
abstract: BACKGROUND
  The implantable cardioverter-defibrillator (ICD) prevents sudden cardiac death in high-risk patients with hypertrophic cardiomyopathy (HCM). However, recently concerns have been raised regarding the performance of transvenous high-voltage ICD leads (HVL) in this population.
  
  
  OBJECTIVE
  The purpose of this retrospective, multicenter study was to assess the safety and efficacy of HVL in high-risk HCM patients.
  
  
  METHODS
  The study population consisted of HCM patients who received HVL ICDs and were subsequently followed at seven centers in the United States. Kaplan-Meier survival rates were calculated for HVL and patients. HVL failure was a malfunction caused by a noniatrogenic defect.
  
  
  RESULTS
  Between 1992 and 2007, 324 HCM patients (mean age 47 +/- 16 years) received 343 HVL from three major manufacturers. The average HVL implant duration was 3.3 +/- 2.8 years. Overall, the HVL failure rate was 1.4%/year. However, two models (Sprint Fidelis and Transvene, Medtronic, Inc.) accounted for 60% of HVL failures. Survival probabilities for HVL and patients at 10 years were 93% and 91%, respectively. No deaths or serious injuries were reported, although inappropriate shocks occurred in 12% of cases.
  
  
  CONCLUSIONS
  This multicenter experience shows that HVLs are safe and effective in high-risk HCM patients. However, differences in failure rates were found between lead models.
authors.affiliation: Minneapolis Heart Institute Foundation, Minneapolis, Minnesota 55407, USA. Rhauser747@aol.com
authors.forename: Robert G
authors.initials: RG
authors.lastname: Hauser
authors.forename: Barry J
authors.initials: BJ
authors.lastname: Maron
authors.forename: Joseph E
authors.initials: JE
authors.lastname: Marine
authors.forename: Rachel
authors.initials: R
authors.lastname: Lampert
authors.forename: Alan H
authors.initials: AH
authors.lastname: Kadish
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Winters
authors.forename: David L
authors.initials: DL
authors.lastname: Scher
authors.forename: Mazda
authors.initials: M
authors.lastname: Biria
authors.forename: Amit
authors.initials: A
authors.lastname: Kalia
mesh_terms: D000328:Adult; D002312:Cardiomyopathy, Hypertrophic / Q000628:therapy*; D017147:Defibrillators, Implantable; D004868:Equipment Failure; D004869:Equipment Safety; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate; D016896:Treatment Outcome