title: The Occurrence of Implantable Cardioverter Defibrillator Therapies After Generator Replacement in Patients Who No Longer Meet Primary Prevention Indications.
abstract: At the time of generator replacement, after ICD implantation for primary prevention, many patients may no longer meet implantation criteria. We investigated the occurrence of ICD therapy after generator replacement in patients initially implanted ICD for primary prevention.
  
  
  
  Patients from 3 hospitals undergoing ICD generator replacement, who were initially implanted for primary prevention, were retrospectively evaluated for occurrence of appropriate ICD therapy after generator replacement. Patients were categorized as to whether or not they had appropriate ICD therapy during their first battery life, and by their left ventricular ejection fraction (LVEF) before generator replacement.
  
  
  
  Data from 168 patients were analyzed, with average follow-up after generator replacement of 41.2 ± 26.5 months. Seventy-six (45.2%) patients had ventricular arrhythmia episodes (>180 beats per minutes) and 63 (37.5%) received appropriate ICD therapy during the first battery life. Among 105 patients without ICD therapy before generator replacement, those with an LVEF ≤35% before ICD replacement had higher occurrence of ICD therapy after generator replacement than patients with an LVEF ≥36%. Patients who no longer met primary prevention ICD indications (no ICD therapy and LVEF ≥36% before generator replacement) showed a lower risk for ICD therapy after generator replacement (11.6% over 5-year follow-up).
  
  
  
  In patients without ICD therapy before generator replacement, low LVEF (≤35%) contributed to future ICD therapy. In patients initially undergoing ICD implantation for primary prevention, history of ICD therapy during the first battery life and LVEF should be utilized for risk stratification at the time of generator replacement.
authors.affiliation: Department of Medicine, Good Samaritan Hospital, Cincinnati, Ohio, USA.
authors.forename: Hiro
authors.initials: H
authors.lastname: Kawata
authors.affiliation: Division of Cardiology, Department of Medicine, Loyola University Chicago, Stritch School of Medicine, Loyola University Medical Center, Maywood, Illinois, USA.
authors.forename: Taishi
authors.initials: T
authors.lastname: Hirai
authors.affiliation: Division of Cardiology, Department of Medicine, Loyola University Chicago, Stritch School of Medicine, Loyola University Medical Center, Maywood, Illinois, USA.
authors.forename: Demetrios
authors.initials: D
authors.lastname: Doukas
authors.affiliation: Division of Cardiology, Department of Medicine, Loyola University Chicago, Stritch School of Medicine, Loyola University Medical Center, Maywood, Illinois, USA.
authors.forename: Rie
authors.initials: R
authors.lastname: Hirai
authors.affiliation: Department of Medicine, Good Samaritan Hospital, Cincinnati, Ohio, USA.
authors.forename: Jenni
authors.initials: J
authors.lastname: Steinbrunner
authors.affiliation: Department of Medicine, Good Samaritan Hospital, Cincinnati, Ohio, USA.
authors.forename: John
authors.initials: J
authors.lastname: Wilson
authors.affiliation: National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Noda
authors.affiliation: University of California, San Diego, Sulpizio Family Cardiovascular Center, La Jolla, California, USA.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Hsu
authors.affiliation: University of California, San Diego, Sulpizio Family Cardiovascular Center, La Jolla, California, USA.
authors.forename: David
authors.initials: D
authors.lastname: Krummen
authors.affiliation: University of California, San Diego, Sulpizio Family Cardiovascular Center, La Jolla, California, USA.
authors.forename: Gregory
authors.initials: G
authors.lastname: Feld
authors.affiliation: Division of Cardiology, Department of Medicine, Loyola University Chicago, Stritch School of Medicine, Loyola University Medical Center, Maywood, Illinois, USA.
authors.forename: David
authors.initials: D
authors.lastname: Wilber
authors.affiliation: Division of Cardiology, Department of Medicine, Loyola University Chicago, Stritch School of Medicine, Loyola University Medical Center, Maywood, Illinois, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Santucci
authors.affiliation: University of California, San Diego, Sulpizio Family Cardiovascular Center, La Jolla, California, USA.
authors.forename: Ulrika
authors.initials: U
authors.lastname: Birgersdotter-Green
mesh_terms: D000368:Aged; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D016757:Death, Sudden, Cardiac / Q000517:prevention & control*; D017147:Defibrillators, Implantable; D020878:Device Removal; D004554:Electric Countershock / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D011211:Electric Power Supplies; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011322:Primary Prevention / Q000295:instrumentation*; D016016:Proportional Hazards Models; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012189:Retrospective Studies; D012307:Risk Factors; D013318:Stroke Volume; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States; D016277:Ventricular Function, Left
keywords: heart failure; implantable cardioverter defibrillator; left ventricular ejection fraction; primary prevention; sudden cardiac death