Outcome of advisory implantable cardioverter-defibrillator replacement: One-year follow-up Paul A. Gould, MBBS, PhD,* Lorne J. Gula, MD,* Jean Champagne, MD, † Jeffrey S. Healey, MD, ‡ Doug Cameron, MD, § Christophers Simpson, MD, # Bernard Thibault, MD, ¶ Arnold Pinter MD,  Stanley Tung, MD,** Laurence Sterns, MD, †† David Birnie, MD, ‡‡ Derek Exner, MD, §§ Ratika Parkash, MD, ## Allan C. Skanes, MD,* Raymond Yee, MD,* George J. Klein, MD,* Andrew D. Krahn, MD* From the *University of Western Ontario, London, Ontario, † Quebec Heart Institute, Laval Hospital, Quebec City, Quebec, ‡ Hamilton Health Sciences Center, Hamilton, Ontario, § University Health Network, Toronto, Ontario, # Queen’s University, Kingston, Ontario, ¶ Montreal Heart Institute, Montreal, Quebec,  St. Michael’s Hospital, Toronto, Ontario, **St. Paul’s Hospital, Vancouver, British Columbia, †† Vancouver Island Health Authority, Victoria, British Columbia, ‡‡ Ottawa Heart Institute, Ottawa, Ontario, §§ Foothills Hospital, Calgary, Alberta, ## QEII Health Sciences Center, Halifax, Nova Scotia. BACKGROUND Implantable cardioverter defibrillator (ICD) gener- ator advisories present management dilemmas for physicians re- garding competing risks of ICD failure and replacement-related complications. There is currently a paucity of long-term data concerning the complications associated with advisory ICD re- placement. OBJECTIVE In a large multicenter advisory ICD generator replace- ment cohort followed for 12 months, we aimed to assess replace- ment-related complications by performing a case-control determi- nation of complication risk factors to identify characteristics that could assist with advisory ICD replacement decision making. METHODS Twelve large ICD implanting centers reviewed the 1-year follow-up outcome of advisory ICDs replaced between Oc- tober 2004 and October 2005. The complication cohort was char- acterized and compared in a nested case-control analysis with age- and gender-matched controls without complications from the same replacement population. RESULTS At the 12 participating institutions, 451 of 2635 advi- sory ICD devices were replaced (17.1%). Over 355  204 days of follow-up, there were 41 (9.1%) complications; 27 (5.9%) required reoperation and included two deaths. There were 14 minor com- plications (3.1%). Multivariate analysis demonstrated that the number of previous pocket procedures was associated with an increase in complications and that combined consultant and fel- low operators was associated with a decrease in complications compared with a single operator alone. CONCLUSIONS Complications from advisory ICD generator re- placement are frequent and include infection and, rarely, death. The risk of replacement is increased in patients with multiple previous pocket procedures. KEYWORDS Implantable cardioverter defibrillator; Advisory; Infec- tion; Complications; Risk factors (Heart Rhythm 2008;5:1675–1681) © 2008 Heart Rhythm Society. All rights reserved. Introduction There was a dramatic increase in the number of implantable cardioverter-defibrillator (ICD) generator advisories in 2005. 1 The clinical implications of these advisories have caused management dilemmas for physicians. Guidelines were published by the Heart Rhythm Society to provide physicians with a framework to enable appropriate manage- ment decisions in such circumstances. 2 These guidelines called for collection of accurate data to guide decisions regarding competing risks for patients in the face of an advisory. Thus there is a need for additional multicenter data that can substantiate current management strategies. Prior research has demonstrated complication rates for ICD generator replacement ranging from 1.24% to 8.1%, 1,3,4 depending on the definition of postoperative complications used. These studies have been limited by their focus on a single type of complication, 5,6 examination of mixed ICD and pacemaker cohorts including predominantly new im- plants, 5,6 single-center experience, 3,4 and limited postoperative follow-up. 1 Additionally, no prior study has investigated po- tential risk factors focused on ICD replacement-related com- plications. In the current study, we assessed the 1-year outcome of a large advisory ICD replacement cohort in 12 of the largest ICD implanting centers in Canada. We sought to identify predictors of complications and thereby identify patients at increased risk from ICD generator replacement. This infor- Address reprint requests and correspondence: Dr. Andrew Krahn, Arrhyth- mia Service, London Health Sciences Centre, 339 Windermere Road, London, Ontario, Canada, N6A 5A5. E-mail address: akrahn@uwo.ca. (Received August 4, 2008; accepted September 17, 2008.) 1547-5271/$ -see front matter © 2008 Heart Rhythm Society. All rights reserved. doi:10.1016/j.hrthm.2008.09.020