December 8, 2008 - New research reveals patients with implantable cardioverter defibrillators (ICDs) who have had multiple, previous pocket procedures are at an increased risk of complications after ICD replacement.
The new study published in the December 2008 edition of the HeartRhythm Journal, the official journal of the Heart Rhythm Society, further reports a higher than expected overall ICD replacement complication rate compared to findings from earlier studies.
The large, multicenter study, led by Andrew Krahn, M.D., from the London Health Sciences Center in London, Ontario, involved participation from 12 of the largest ICD implanting centers in Canada. The purpose of the study was to identify predictors of ICD replacement complications and investigate those complications in order to determine what causes patients to be at a greater risk. The study proves that multiple, previous pocket procedures are a predictor of ICD replacement complications. Patients who have already had multiple pocket procedures are at a greater risk of complication.
“No prior research has investigated the potential risk factors associated with ICD replacement, more specifically, what makes some patients more at-risk than others,” said author Andrew Krahn, M.D. “Study findings will help physicians better understand complication risks for patients who may need ICD replacement, and ultimately provide better care for their patients.”
Among the 12 participating centers, 451 out of 2,635 advisory ICD devices were replaced between October 2004 and October 2005. Over a one-year follow-up period, results show that patients experience various levels of complications, both major and minor. Major complications can include serious infection requiring system removal, and bleeding or ICD malfunction necessitating re-operation, while minor complications can include minor infection or worsening of other medical conditions. Of the 451 patients who underwent ICD replacement, 41 (9.1 percent) experienced complications, 27 (5.9 percent) required re-operation and included two deaths, and 14 patients (3.1 percent) experienced minor complications.
For more information: www.heartrhythmjournal.com
May 06, 2026 
