title: Safety and efficiency of ventricular pacing prevention with an AAI-DDD changeover mode in patients with sinus node disease or atrioventricular block: impact on battery longevity-a sub-study of the ANSWER trial.
abstract: OBJECTIVE
  This ANSWER (EvaluAtioN of the SafeR mode in patients With a dual chambER pacemaker indication) sub-study assesses safety and effectiveness of SafeR™ and the impact of ventricular pacing (VP) prevention on anticipated device longevity and replacement rate.
  
  
  RESULTS
  Patients implanted for atrioventricular block (AVB, n = 310) or sinus node dysfunction (SND, n = 336) were randomly assigned to SafeR (n = 314) or DDD (n = 318) and followed for 36 months. Safety, median VP, estimated device longevity (mean difference, 95% confidence interval [CI]), and anticipated replacement rates were analysed by pacing mode and implant indication. No difference in mortality, syncope, or mode intolerance was observed between randomization groups regardless of the indication. Ventricular pacing on SafeR vs. DDD was 11.5 vs. 93.6% in the overall population (P < 0.001), 89.2 vs. 83.8% in permanent AVB (P = 0.944), 53.5 vs. 98.2% in intermittent AVB (P < 0.001), and 2.2 vs. 84.7% in SND (P < 0.001). Anticipated median device longevity increased on SafeR by 14 [Q1 10; Q3 17] months [10; 17] (P < 0.001) in the overall population, 9 months [-5; 22] (P = 0.193) in permanent AVB, 14 months [8; 19] (P < 0.001) in intermittent AVB, and 14 months [9; 19] (P < 0.001) in SND. In intermittent AVB and SND, prolonged estimated battery longevity translated into the prevention of one anticipated replacement in at least 23% of patients.
  
  
  CONCLUSIONS
  SafeR was effective in reducing VP in intermittent AVB and in SND. No effect was observed in permanent AVB. No safety issue was observed. Ventricular pacing reduction by SafeR translated into relevant estimated prolongation of device longevity and anticipated reduction of required replacements.
authors.affiliation: Department of Cardiology and Angiology, Charité University Hospital, Berlin, Germany Department of Cardiology, Havelland Kliniken Nauen, Ketziner Strasse 21, 14641 Nauen, Germany martin.stockburger@charite.de.
authors.forename: Martin
authors.initials: M
authors.lastname: Stockburger
authors.affiliation: Arrhythmia Unit, Cardiology Department, University Hospital, Grenoble, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Defaye
authors.affiliation: Arrhythmia Unit, Clinique Pasteur, Toulouse, France.
authors.forename: Serge
authors.initials: S
authors.lastname: Boveda
authors.affiliation: Arrhythmia Department, Hospital of Eastern Slovakia, Institute of Cardiovascular Diseases, Kosice, Slovakia.
authors.forename: Branislav
authors.initials: B
authors.lastname: Stancak
authors.affiliation: InParys, A. Paré Private Hospital, Neuilly sur Seine, France.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Lazarus
authors.affiliation: Hanusch Krankenhaus, Vienna, Austria.
authors.forename: Johann
authors.initials: J
authors.lastname: Sipötz
authors.affiliation: Azienda Ospedaliera S. Maria, Terni, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Nardi
authors.affiliation: Sorin Group International SA, Lausanne, Switzerland.
authors.forename: Mara
authors.initials: M
authors.lastname: Rolando
authors.affiliation: Arrhythmia Department, Cardiovascular Institute, San Carlos University Hospital, Madrid, Spain Arrhythmia Department, Hospital Ramón y Cajal, Madrid, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Moreno
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D054537:Atrioventricular Block / Q000628:therapy*; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects / Q000379:methods*; D011211:Electric Power Supplies; D004867:Equipment Design / Q000379:methods*; D005060:Europe; D005260:Female; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial / Q000009:adverse effects* / Q000145:classification; D011446:Prospective Studies; D012804:Sick Sinus Syndrome / Q000628:therapy*; D016037:Single-Blind Method; D016896:Treatment Outcome
keywords: Atrioventricular block; Battery impedance; Device longevity; Pacemaker mode selection; Pacing prevention; Replacement; SafeR; Sinus node dysfunction