title: Safety and efficacy of a totally subcutaneous implantable-cardioverter defibrillator.
abstract: BACKGROUND
  The most frequent complications associated with implantable cardioverter-defibrillators (ICDs) involve the transvenous leads. A subcutaneous implantable cardioverter-defibrillator (S-ICD) has been developed as an alternative system. This study evaluated the safety and effectiveness of the S-ICD System (Cameron Health/Boston Scientific) for the treatment of life-threatening ventricular arrhythmias (ventricular tachycardia/ventricular fibrillation).
  
  
  RESULTS
  This prospective, nonrandomized, multicenter trial included adult patients with a standard indication for an ICD, who neither required pacing nor had documented pace-terminable ventricular tachycardia. The primary safety end point was the 180-day S-ICD System complication-free rate compared with a prespecified performance goal of 79%. The primary effectiveness end point was the induced ventricular fibrillation conversion rate compared with a prespecified performance goal of 88%, with success defined as 2 consecutive ventricular fibrillation conversions of 4 attempts. Detection and conversion of spontaneous episodes were also evaluated. Device implantation was attempted in 321 of 330 enrolled patients, and 314 patients underwent successful implantation. The cohort was followed for a mean duration of 11 months. The study population was 74% male with a mean age of 52±16 years and mean left ventricular ejection fraction of 36±16%. A previous transvenous ICD had been implanted in 13%. Both primary end points were met: The 180-day system complication-free rate was 99%, and sensitivity analysis of the acute ventricular fibrillation conversion rate was >90% in the entire cohort. There were 38 discrete spontaneous episodes of ventricular tachycardia/ventricular fibrillation recorded in 21 patients (6.7%), all of which successfully converted. Forty-one patients (13.1%) received an inappropriate shock.
  
  
  CONCLUSIONS
  The findings support the efficacy and safety of the S-ICD System for the treatment of life-threatening ventricular arrhythmias.
authors: Ohio State University, Columbus, OH, USA.
authors: Raul
authors: R
authors: Weiss
authors: Bradley P
authors: BP
authors: Knight
authors: Michael R
authors: MR
authors: Gold
authors: Angel R
authors: AR
authors: Leon
authors: John M
authors: JM
authors: Herre
authors: Margaret
authors: M
authors: Hood
authors: Mayer
authors: M
authors: Rashtian
authors: Mark
authors: M
authors: Kremers
authors: Ian
authors: I
authors: Crozier
authors: Kerry L
authors: KL
authors: Lee
authors: Warren
authors: W
authors: Smith
authors: Martin C
authors: MC
authors: Burke
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D017147:Defibrillators, Implantable; D004869:Equipment Safety; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D017180:Tachycardia, Ventricular / Q000628:therapy*; D016896:Treatment Outcome
keywords: defibrillators, implantable; heart arrest; tachycardia