title: Analyses of inappropriate shocks in a Spanish ICD primary prevention population: Predictors and prognoses.
abstract: BACKGROUND
  ICDs have been demonstrated to be highly effective in the primary prevention of sudden death, but inappropriate shocks (IS) occur frequently and represent one of the most important adverse effects of ICDs. The aim of this study was to analyze IS and identify the clinical predictors and prognostic implications of ISs in a real-world primary prevention ICD population.
  
  
  METHODS
  This multicenter retrospective study was performed in 13 centers with experience in the field of ICD implantation (at least 30 per year) and ICD follow-up in Spain. All consecutive patients who underwent ICD implantation for primary prevention between January 2008 and May 2014 were included.
  
  
  RESULTS
  One-thousand-sixteen patients were included, and 4 (0.39%) were lost to follow-up. Two-hundred-seventeen (21.4%) patients suffered from shock; 69 (6.8%) of these patients experienced IS, and 154 (15.4%) experienced appropriate shocks (AS). Age (<65 years, hazard ratio (HR) 2.588 [95% CI 1.282-5.225]; p=0.008), history of atrial fibrillation (HR 2.252 [95% CI 1.230-4.115]; p=0.009), non-ischemic myocardiopathy (HR 2.258 [95% CI 1.090-4.479]; p=0.028), and cardiac resynchronization therapy (HR 0.385 [95% CI 0.200-0.740]; p=0.004) were identified as IS predictors in a multivariate analysis. IS was not associated with rehospitalization due to heart failure, myocardial infarction, cardiovascular mortality or all-cause mortality.
  
  
  CONCLUSIONS
  This analysis of our national registry identified the independent IS predictors of age, atrial fibrillation history and cardiac resynchronization therapy and suggests that ISs are not linked to poorer clinical endpoints.
authors.affiliation: Hospital Universitari Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain. Electronic address: fecia82@gmail.com.
authors.forename: Agustín
authors.initials: A
authors.lastname: Fernández-Cisnal
authors.affiliation: Hospital Universitario Virgen del Rocío, Seville, Spain.
authors.forename: Álvaro
authors.initials: Á
authors.lastname: Arce-León
authors.affiliation: Hospital Universitario Virgen del Rocío, Seville, Spain.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Arana-Rueda
authors.affiliation: Hospital Universitario Santiago de Compostela, A Coruña, Spain.
authors.forename: Moisés
authors.initials: M
authors.lastname: Rodríguez-Mañero
authors.affiliation: Hospital Universitario Santiago de Compostela, A Coruña, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: González-Cambeiro
authors.affiliation: Hospital Universitario San Juan, Alicante, Spain.
authors.forename: Jose
authors.initials: J
authors.lastname: Moreno-Arribas
authors.affiliation: Hospital de Basurto, Bilbao, Spain.
authors.forename: Larraitz
authors.initials: L
authors.lastname: Gaztañaga
authors.affiliation: Hospital Universitari Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain.
authors.forename: Rocío
authors.initials: R
authors.lastname: Castillo Poyo
authors.affiliation: Complejo Hospitalario Universitario de Vigo, Pontevedra, Spain.
authors.forename: Pilar
authors.initials: P
authors.lastname: Cabanas-Grandío
authors.affiliation: Hospital Virgen de la Salud, Toledo, Spain.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Arias
authors.affiliation: Hospital Universitario La Fe, Valencia, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Andrés de la Huerta
authors.affiliation: Hospital Clínico Universitario de Valencia, Valencia, Spain.
authors.forename: Juan Miguel
authors.initials: JM
authors.lastname: Sánchez Gómez
authors.affiliation: Hospital Universitario Santiago de Compostela, A Coruña, Spain.
authors.forename: Luis
authors.initials: L
authors.lastname: Martínez-Sande
authors.affiliation: Hospital Universitario Virgen del Rocío, Seville, Spain.
authors.forename: Alonso
authors.initials: A
authors.lastname: Pedrote
mesh_terms: D000367:Age Factors; D000368:Aged; D001281:Atrial Fibrillation / Q000453:epidemiology; D058406:Cardiac Resynchronization Therapy / Q000706:statistics & numerical data; D016757:Death, Sudden, Cardiac / Q000517:prevention & control*; D017147:Defibrillators, Implantable / Q000009:adverse effects / Q000592:standards; D004554:Electric Countershock / Q000009:adverse effects / Q000379:methods; D019544:Equipment Failure Analysis / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011322:Primary Prevention / Q000379:methods; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013030:Spain / Q000453:epidemiology; D017180:Tachycardia, Ventricular / Q000628:therapy*; D016896:Treatment Outcome
keywords: Implantable cardioverter device; Inappropriate shock; Primary prevention