DENVER – Encasing implantable cardioverter-defibrillators and cardiac resynchronization therapy devices in a proprietary antibiotic-impregnated envelope during implantation was associated with a low 90-day major infection rate in an interim analysis of a large prospective multicenter study.
The CITADEL/CENTURION study involves 1,000 patients who underwent ICD or CRT device replacement using the antibacterial envelope at 55 U.S. centers. A major device infection – defined as an infection involving the device pocket, deep tissue, or endocarditis – occurred in one patient through 3 months of prospective follow-up, for an infection incidence of 0.1%, Dr. Charles Henrikson reported at the annual meeting of the Heart Rhythm Society.
Dr. Charles Henrikson
CITADEL/CENTURION is not a randomized trial. Instead, the control group consists of 533 Canadian patients in a published study, all of whom underwent ICD or CRT replacement because of device advisories or recalls. The major device infection rate in this retrospective study (JAMA 2006;295:1907-11) during a mean 2.7 months following device replacement was 1.9%, or roughly 19-fold greater than in CITADEL/CENTURION, noted Dr. Henrikson of Oregon Health and Science University, Portland.
Device replacement is a known risk factor for major device infections, which carry a substantial toll in terms of morbidity, mortality, and expense.
The antibacterial envelope, known as AIGISRx, has received Food and Drug Administration approval and is commercially available. The antibacterial envelope is designed to prevent device migration as well as infections. "It changes the device from something that’s slick and slides right in into something with an incredibly high coefficient of friction, so you need to make a larger pocket to put it in. That’s why we’re paying a lot of attention to the hematoma rate," according to Dr. Henrikson.
The device consists of a nonresorbable polypropylene mesh coated with a resorbable polymer layer, which releases rifampin and minocycline for 7-10 days. These two antibiotics are active against the pathogens that cause most device infections, including both methicillin-sensitive and -resistant Staphylococcus aureus as well as S. epidermis.
The indication for device replacement in CITADEL/CENTURION was end of battery life in about three-quarters of patients, with device upgrades and lead revisions accounting for nearly all of the rest. Explantation because of device infection was a contraindication to study participation. All subjects were on perioperative prophylactic antibiotics, as were the historical controls.
The chief device-related complication recorded during the study was major pocket hematoma requiring a change in patient management, typically open drainage or transfusion. The complication occurred in 1.5% of patients, as compared to 2.25% of the historical controls.
Two of the 1,000 patients developed generalized rashes thought by independent reviewers to be possibly related to AIGISRx.
The plan is to monitor CITADEL/CENTURION participants for device infections and mechanical complications through 12 months, Dr. Henrikson explained. Only the 3-month data were available for presentation at a late-breaking clinical trials session during Heart Rhythm 2013.
CITADEL/CENTURION is sponsored by TYRX, which markets AIGISRx. Dr. Henrikson reported having received research support from the company.