Inflammatory reaction to TYRX antibacterial envelope mimicking infection

Antibacterial envelopes are commonly used to prevent cardiac implantable electronic device (CIED) infection. In patients at high risk of device infection, the use of the TYRX envelope (Medtronic, Inc.) was shown to reduce major device infection by 40% in the worldwide randomized antibiotic envelope infection prevention trial (WRAP‐IT). We report three cases of purulent, culture‐negative discharge from device pockets after the use of a TYRX envelope. Two cases were managed conservatively while the other one resulted in the extraction of a 15‐year‐old implantable cardioverter‐defibrillator (ICD) lead. We suspect these three cases could represent possible allergic or other inflammatory reaction to the TYRX envelope as opposed to infection. In the WRAP‐IT trial, no bacteria was identified in 11 out of 14 (79%) pocket infection in theTYRX arm. We suspect that some of these “infections” were inflammatory reactions as was seen in our patients.