• April 2021

    Antibacterial “envelope” found to help reduce CIED infections

Findings of a clinical study demonstrated that the use of an antibiotic-eluting envelope placed around a cardiac implantable electronic device (CIED) during implantation reduced the incidence of major infections by 40 percent compared implantation without the antibacterial envelop. The study, called the Worldwide Randomized Antibiotic Envelope Infection Prevention Trial (WRAP-IT; NCT02277990), evaluated the safety and efficacy of the Medtronic TYRXTM Absorbable Antibacterial Envelope in adult patients at 181 centers in 25 countries with 776 implanting physicians.

The WRAP-IT study report was published in the New England Journal of Medicine in 2019 with Hafiza Khan, MD, FACC, FHRS, an interventional cardiologist at Baylor Scott and White The Heart Hospital in Plano, TX and researcher with Baylor Scott & White Research Institute (BSWRI) among the authors. Dr. Khan’s team at Baylor Scott & White was a top enroller in the international study.


Approximately 1.5 million people worldwide undergo CIED implantation or revision surgery each year. The cardiac monitoring and cardiac rhythm management devices market is projected to reach USD 25.05 billion by 2024 from USD 20.67 billion in 2019. As use and prevalence of CIEDs continue to grow, bacterial infection, which occurs in 1-4 percent of CIED patients, steadily remains a cause of CIED complications. Most infections occur within 90 days and major infections can require CIED removal and long-term antibiotic therapy and increase the risk of death. The average cost of an infection is over $40,000

Antibacterial envelope

The TYRXTM device is a single-use multifilament knitted mesh envelope that surrounds the CIED and elutes minocycline and rifampin into the nearby tissue for at least 7 days. The envelope is then absorbed in 9 weeks.

WRAP-IT study

With 6983 participants, the WRAP-IT study was the largest multi-center, randomized, global, prospective, single blind, post-market interventional CIED trial to date. The primary outcome measure was the occurrence of a major CIED infection within 12 months of implantation. Adult participants were recruited from among those seeking de novo CIED implantation, replacement, upgrade, or revision. The trial was designed to select patients at increased risk for CIED pocket infection and all patients received standard-of-care prophylactic intravenous antibiotics.

Major infections occurred in 25 patients who received the envelope and 42 patients who did not. The envelope was successfully implanted in 99.7% of attempts. Overall, the study showed that the antibiotic envelope significantly decreased the incidence of major infection without increasing complications.

Cardiac Surgery Resources in Plano, TX

Baylor Scott & White The Heart Hospital—Plano is a nationally ranked heart surgery program, and in collaboration with BSWRI, is a well-recognized clinical research center. Since 2008, more than 3,000 patients have participated in clinical trials at Baylor Scott & White The Heart Hospital – Plano, with over 70 trials completed and more than 80 active trials currently underway.

Dr. Khan was recruited to Plano, TX in 2001 from Brigham and Women’s Hospital, where she received fellowship training in cardiovascular disease and clinical cardiac electrophysiology. Her research publications have focused on evaluating techniques for managing cardiac pacing defects and identifying the structural correlates of cardiac functional properties.  

Baylor Scott & White The Heart Hospital Plano is nationally ranked in the top 25 hospitals for cardiology and heart surgery by the US News and World Report. It has also received three-stars, the highest rating, from the Society of Thoracic Surgeons (STS) for outstanding surgical quality.