Clinical Presentation, Timing, and Microbiology of CIED Infections: An Analysis of the WRAP-IT Trial

OBJECTIVES This study characterized the microbiology of major cardiac implantable electronic device (CIED) infections that occurred during the WRAP-IT (Worldwide Randomized Antibiotic Envelope Infection Prevention Trial) study.BACKGROUND The WRAP-IT study offers a unique opportunity for further understanding of the pathogens involved in major CIED infections in a prospective dataset, with implications for clinical practice and infection management.METHODS A total of 6,800 patients randomized 1:1 to receive an antibacterial envelope or not (control subjects) were included in this analysis. Patient characteristics, infection manifestation (pocket vs. systemic), and infection microbiology were evaluated through all follow-up (36 months). Data were analyzed using Cox proportional hazards regression.RESULTS A total of 3,371 patients received an envelope, and 3,429 patients were control subjects. Major CIED infection occurred in 32 patients who received an envelope and 51 control subjects (36-month Kaplan-Meier estimated event rate, 1.3% and 1.9%, respectively; p = 0.046). A 61% reduction in major pocket infection was observed within 12 months of the procedure in the envelope group (hazard ratio: 0.39, 95% confidence interval: 0.21 to 0.73; p 0.003). Among 76 patients with major infections who had a sample taken, causative pathogens were identified in 47 patients. Staphylococcus spedes were the predominate pathogen (n = 31) and envelope use resulted in a 76% reduction in Staphylococcus-related pocket infections (n = 4 vs. 17; p = 0.010). Envelope use was not associated with delayed onset of pocket infections and did not affect the presentation of infections.CONCLUSIONS Antibacterial envelope use resulted in a significant reduction of major OED pocket infections and was particularly effective against Staphylococcus species, the predominant cause of pocket infections. (C) 2021 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation.