title: High prevalence of asymptomatic bacterial colonization of rhythm management devices.
abstract: OBJECTIVE
  Recent work has been focused on causes of and risk factors for rhythm management device infections. The aim of this study was to elucidate whether patients may be asymptomatic carriers of bacteria on their rhythm management device, possibly allowing later manifestation of infection.
  
  
  RESULTS
  A total of 108 devices were changed for battery depletion between April 2005 and February 2006 in asymptomatic patients who were examined for evidence of bacterial DNA on the device and in the surrounding tissue using single strand conformation polymorphism analysis (SSCP). Follow-up was for 23.4 months. In 47.2% of the patients, bacterial DNA was demonstrated on the device, which had been in place for 64.1 months. The sequences identified bacterial strains that are untypical for clinical device infections. Staphylococci were demonstrated in only 3.7% of the patients and they became symptomatic within the observation interval; all others remained asymptomatic. The known risk factors for device infections did not correlate with the demonstration of bacterial DNA in this population. Common cohabitation was identified among the strains found.
  
  
  CONCLUSIONS
  A large proportion of patients carry bacteria on their pacemaker or implantable cardioverter defibrillator asymptomatically. The strains found differ from those commonly seen in clinically evident device infections. Common risk factors for device infection did not correlate with the presence of DNA.
authors.affiliation: Department of Cardiac, Thoracic, Transplantation and Vascular Surgery, Hannover Medical School, Carl-Neuberg-Strasse, D-30625 Hanover, Germany. pichlmaier.maximilian@mh-hannover.de
authors.forename: Maximilian
authors.initials: M
authors.lastname: Pichlmaier
authors.forename: Verena
authors.initials: V
authors.lastname: Marwitz
authors.forename: Christian
authors.initials: C
authors.lastname: Kühn
authors.forename: Michael
authors.initials: M
authors.lastname: Niehaus
authors.forename: Gunnar
authors.initials: G
authors.lastname: Klein
authors.forename: Christof
authors.initials: C
authors.lastname: Bara
authors.forename: Axel
authors.initials: A
authors.lastname: Haverich
authors.forename: Wolf-Rainer
authors.initials: WR
authors.lastname: Abraham
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001424:Bacterial Infections / Q000453:epidemiology*; D017147:Defibrillators, Implantable / Q000382:microbiology* / Q000706:statistics & numerical data*; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009205:Myocarditis / Q000453:epidemiology*; D010138:Pacemaker, Artificial / Q000382:microbiology* / Q000706:statistics & numerical data*; D015995:Prevalence; D016459:Prosthesis-Related Infections / Q000453:epidemiology*; D018570:Risk Assessment; D012307:Risk Factors