title: Longevity of implantable cardioverter-defibrillators for cardiac resynchronization therapy in current clinical practice: an analysis according to influencing factors, device generation, and manufacturer.
abstract: OBJECTIVE
  Device replacement at the time of battery depletion of implantable cardioverter-defibrillators (ICDs) may carry a considerable risk of complications and engenders costs for healthcare systems. Therefore, ICD device longevity is extremely important both from a clinical and economic standpoint. Cardiac resynchronization therapy defibrillators (CRT-D) battery longevity is shorter than ICDs. We determined the rate of replacements for battery depletion and we identified possible determinants of early depletion in a series of patients who had undergone implantation of CRT-D devices.
  
  
  RESULTS
  We retrieved data on 1726 consecutive CRT-D systems implanted from January 2008 to March 2010 in nine centres. Five years after a successful CRT-D implantation procedure, 46% of devices were replaced due to battery depletion. The time to device replacement for battery depletion differed considerably among currently available CRT-D systems from different manufacturers, with rates of batteries still in service at 5 years ranging from 52 to 88% (log-rank test, P < 0.001). Left ventricular lead output and unipolar pacing configuration were independent determinants of early depletion [hazard ratio (HR): 1.96; 95% 95% confidence interval (CI): 1.57-2.46; P < 0.001 and HR: 1.58, 95% CI: 1.25-2.01; P < 0.001, respectively]. The implantation of a recent-generation device (HR: 0.57; 95% CI: 0.45-0.72; P < 0.001), the battery chemistry and the CRT-D manufacturer (HR: 0.64; 95% CI: 0.47-0.89; P = 0.008) were additional factors associated with replacement for battery depletion.
  
  
  CONCLUSIONS
  The device longevity at 5 years was 54%. High left ventricular lead output and unipolar pacing configuration were associated with early battery depletion, while recent-generation CRT-Ds displayed better longevity. Significant differences emerged among currently available CRT-D systems from different manufacturers.
authors.affiliation: Fondazione Policlinico S. Matteo IRCCS, Pavia, Italy Dipartimento di Cardiologia, A.O. Ospedale Maggiore di Crema, Largo Ugo Dossena 2, Crema (Cremona) 26013, Italy maurizio.landolina02@gmail.com.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Landolina
authors.affiliation: Ospedali Civili, Brescia, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Curnis
authors.affiliation: Ospedale Civile Maggiore di Borgo Trento, Verona, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Morani
authors.affiliation: A.S. Ospedaliera S. Croce e Carle, Cuneo, Italy.
authors.forename: Antonello
authors.initials: A
authors.lastname: Vado
authors.affiliation: Seconda Università di Napoli A.O. Monaldi, Naples, Italy.
authors.forename: Ernesto
authors.initials: E
authors.lastname: Ammendola
authors.affiliation: Azienda Ospedaliera dei Colli - Monaldi, Naples, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: D'onofrio
authors.affiliation: Clinica Mediterranea, Naples, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Stabile
authors.affiliation: Treviso Hospital 'Ca' Foncello', Treviso, Italy.
authors.forename: Martino
authors.initials: M
authors.lastname: Crosato
authors.affiliation: Fondazione Policlinico S. Matteo IRCCS, Pavia, Italy.
authors.forename: Barbara
authors.initials: B
authors.lastname: Petracci
authors.affiliation: Humanitas Research Hospital IRCCS, Rozzano (Milan), Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Ceriotti
authors.affiliation: Ospedali Civili, Brescia, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Bontempi
authors.affiliation: Ospedale Civile Maggiore di Borgo Trento, Verona, Italy.
authors.forename: Martina
authors.initials: M
authors.lastname: Morosato
authors.affiliation: A.S. Ospedaliera S. Croce e Carle, Cuneo, Italy.
authors.forename: Gian Paolo
authors.initials: GP
authors.lastname: Ballari
authors.affiliation: Humanitas Research Hospital IRCCS, Rozzano (Milan), Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Gasparini
mesh_terms: D058409:Cardiac Resynchronization Therapy Devices / Q000145:classification / Q000706:statistics & numerical data; D017147:Defibrillators, Implantable / Q000145:classification* / Q000706:statistics & numerical data*; D020878:Device Removal / Q000706:statistics & numerical data*; D011211:Electric Power Supplies / Q000145:classification / Q000706:statistics & numerical data*; D004867:Equipment Design; D004868:Equipment Failure; D019544:Equipment Failure Analysis / Q000379:methods / Q000706:statistics & numerical data; D006333:Heart Failure / Q000453:epidemiology / Q000517:prevention & control*; D006801:Humans; D007221:Industry / Q000706:statistics & numerical data*; D007558:Italy / Q000453:epidemiology; D013673:Technology Assessment, Biomedical / Q000379:methods / Q000706:statistics & numerical data
keywords: Battery; CRT; Implantable defibrillator; Longevity