title: Prevalence and management of inappropriate detection and therapies in patients with first-generation biventricular pacemaker-defibrillators.
abstract: BACKGROUND
  Tachycardia detection in first-generation biventricular pacemaker-implantable cardioverter defibrillators (BiV ICD) occurs through both the right ventricular (RV) and left ventricular (LV) leads, creating the potential for inappropriate detection and therapies. Little is known regarding the prevalence and management of patients with BiV ICDs and inappropriate detection.
  
  
  RESULTS
  A transvenous, first-generation BiV ICD was implanted in 77 consecutive patients (age 61 +/- 11 years) for drug-refractory heart failure. The mean New York Heart Association class, QRS duration, and ejection fraction were 3.1 +/- 0.4, 168 +/- 24 ms, and 0.19 +/- 0.07, respectively. Among the 77 patients, 17 (22%) experienced inappropriate detection at a mean of 154 +/- 140 days after implantation. Fifteen of the 17 patients (88%) experienced inappropriate ICD therapy. In 16 of the 17 (94%) patients, the cause of inappropriate detection was double counting during sinus (8) or atrial rhythm (3), and nonsustained ventricular tachycardia (5). Despite reprogramming of the ICD, 9 patients (53%) required an additional procedure because of inappropriate therapies, including an upgrade to a dedicated BiV ICD (5), revision of the LV lead (2), ablation of the atrioventricular junction (1), and repeat defibrillation threshold testing (2).
  
  
  CONCLUSIONS
  Inappropriate detection in patients with a first-generation BiV ICD is common and often results in inappropriate ICD therapy. The most common mechanism of inappropriate detection is double counting that often creates the need for additional procedures. Although devices in which tachycardia detection occurs only through the RV lead now are available, close follow-up of the many patients who received a first-generation BiV ICD is necessary.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109-0311, USA. achugh@umich.edu
authors.forename: Aman
authors.initials: A
authors.lastname: Chugh
authors.forename: Christoph
authors.initials: C
authors.lastname: Scharf
authors.forename: Burr
authors.initials: B
authors.lastname: Hall
authors.forename: Peter
authors.initials: P
authors.lastname: Cheung
authors.forename: Eric
authors.initials: E
authors.lastname: Good
authors.forename: Laura
authors.initials: L
authors.lastname: Horwood
authors.forename: Hakan
authors.initials: H
authors.lastname: Oral
authors.forename: Frank
authors.initials: F
authors.lastname: Pelosi
authors.forename: Fred
authors.initials: F
authors.lastname: Morady
mesh_terms: D004867:Equipment Design; D004868:Equipment Failure; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D015995:Prevalence; D012189:Retrospective Studies; D013610:Tachycardia / Q000175:diagnosis* / Q000453:epidemiology / Q000628:therapy*