title: Complication rates associated with transvenous pacemaker implantation in dogs with high-grade atrioventricular block performed during versus after normal business hours.
abstract: BACKGROUND
  Transvenous pacemaker implantation in dogs is associated with a relatively high complication rate. At our institution, pacemaker implantation in dogs with high-grade atrioventricular block (HG-AVB) frequently is performed as an after-hours emergency.
  
  
  OBJECTIVE
  Among dogs with HG-AVB, the rate of major complications is higher when pacemakers are implanted after hours (AH) compared to during business hours (BH).
  
  
  METHODS
  Client-owned dogs with HG-AVB that underwent transvenous pacemaker implantation between January 2002 and December 2012 at the North Carolina State University Veterinary Teaching Hospital.
  
  
  METHODS
  Retrospective medical record review. Two-year follow-up was required for complications analysis.
  
  
  RESULTS
  Major complications occurred in 14/79 dogs (18%) and included lead dislodgement, lead or generator infection, lead or generator migration, and pacing failure. Incidence of major complications was significantly higher AH (10/36, 28%) compared to BH (4/43, 9%; P = .041), and all infectious complications occurred AH. Median survival time for all dogs was 27 months and did not differ between AH and BH groups for either all-cause (P = .70) or cardiac (P = .40) mortality. AH dogs were younger than BH dogs (P = .010), but there were no other clinically relevant differences between BH and AH groups in terms of demographic, clinical, or procedural variables.
  
  
  CONCLUSIONS
  At our institution, AH transvenous pacemaker placement is associated with a higher rate of major complications (especially infections) compared to BH placement. This difference may be because of a variety of human factor differences AH versus BH.
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC.
authors.forename: J L
authors.initials: JL
authors.lastname: Ward
authors.forename: T C
authors.initials: TC
authors.lastname: DeFrancesco
authors.forename: S P
authors.initials: SP
authors.lastname: Tou
authors.forename: C E
authors.initials: CE
authors.lastname: Atkins
authors.forename: E H
authors.initials: EH
authors.lastname: Griffith
authors.forename: B W
authors.initials: BW
authors.lastname: Keene
mesh_terms: D000818:Animals; D054537:Atrioventricular Block / Q000628:therapy / Q000662:veterinary*; D013504:Cardiovascular Surgical Procedures / Q000009:adverse effects / Q000662:veterinary*; D004283:Dog Diseases / Q000628:therapy*; D004285:Dogs; D010138:Pacemaker, Artificial / Q000662:veterinary*; D011183:Postoperative Complications / Q000662:veterinary*; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: Canine; Heart block; Transvenous