The addition of perioperative antibiotic pocket wash plus postoperative oral antibiotics to prophylactic measures, including chlorhexidine skin preparation, preoperative intravenous (IV) antibiotics, and antibiotic envelope strategy, is not beneficial for decreasing the risk for cardiac implantable electronic device (CIED)-related infection. These findings were published in Circulation: Arrhythmia and Electrophysiology.
The ENVELOPE study was an international, prospective, randomized controlled trial conducted between 2016 and 2021. Patients at increased risk for infection (N=1010) undergoing CIED implantation were randomly assigned to receive chlorhexidine skin preparation, preoperative IV antibiotics, and a TYRX-a antibacterial envelope with minocycline and rifampin, with (n=505) or without (n=505) the addition of perioperative antibiotic pocket wash and postoperative antibiotics. A noninferiority limit of 1% was used in this study. High-risk CIED infection was defined as the presence of 2 or more risk factors for infection, such as diabetes, chronic heart failure, chronic use of corticosteroids, and previous CIED infection, among others. The primary outcome was the rate of CIED infection requiring CIED removal at 6 months.
Among patients included in the intervention and control groups, the mean (SD) ages were 70.4 (11.2) and 70.4 (11.9) years, 73% and 71% were men, 86% and 85% were White, 80% and 78% had hypertension, and the mean (SD) BMI was 28.98 (6.8) and 29.06 (7.74) kg/m2, respectively.
At 6 months, 1.0% and 1.2% of intervention and control patients, respectively, required CIED removal due to infection (P =.57).
The patients (n=11) who required CIED removal comprised 7 men and 4 women who were aged between 56 and 83 years, with removal occurring between days 15 and 298. Further analysis of these patients showed that Prevention of Arrhythmia Device Infection Trial (PADIT) scores ranged between 3 and 12 (median, 7.4). A total of 4 patients survived and 7 patients died.
Blood cultures were positive among 9 patients who required CIED removal, specifically for methicillin-sensitive Staphylococcus aureus (n=3), methicillin-sensitive S aureus (n=2), Candida organisms (n=2), Escherichia coli (n=1), and S lugdunensis (n=1).
The strongest independent predictor for CIED infection was previous CIED infection (odds ratio [OR], 9.77; P =.004).
The secondary outcome of CIED pocket hematoma was observed among 30 patients in the intervention group and 36 patients in control group (P =.58). Overall, 7.6% of patients with CIED pocket hematoma subsequently underwent CIED removal due to infection. In addition, outcomes of CIED pocket hematoma were significantly predictive of CIED removal due to infection (OR, 12.9; P <.001).
Of note, previous CIED infection remained significantly predictive of CIED removal due to infection after patients who experienced pocket hematoma were removed from the analysis (OR, 22.95; P =.01).
As the rate of CIED infection was low, this study may not have been sufficiently powered to detect significant between-group differences. Other limitations include disruptions in enrollment due to the COVID-19 pandemic, and the lack of standardized perioperative antibiotic wash regimens.
According to the researchers, “Patients with prior CIED infection are at highest risk for subsequent CIED infection, and nontransvenous devices should be considered in these patients.”
Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Ellis CR, Greenspool AJ, Andriulli JA, et al. Randomized trial of stand-alone use of the antimicrobial envelope in high-risk cardiac device patients. Circ Arrhythm Electrophysiol. 2023;e011740. doi:10.1161/CIRCEP.122.011740