‘Envelope’ reduces cardiac implant infectionsAug. 8, 2013, 9:31 AM
Vanderbilt Heart and Vascular Institute is the first in the United States to use a new fully resorbable “envelope” that encloses implantable cardiac devices, such as pacemakers and internal cardioverter defibrillators (ICDs), and helps prevent surgical site infections.
The AIGISRx R Antibacterial Envelope from TYRX, Inc. received U.S. Food and Drug Administration clearance on May 20.
The envelope is a fully bioresorbable, antibacterial pouch-like mesh envelope that holds cardiac rhythm devices securely in place when implanted in the body. The envelope contains the antimicrobial agents rifampin and minocycline, which are released locally into the tissue, to help reduce infections associated with cardiac implantable electronic devices (CIEDs).
“Over the last several decades, the number of cardiac device infections has risen significantly and out of proportion to the number of cardiac device implantations. With more than 500,000 CIED implantations annually in the U.S., it is critical that the infections associated with these types of procedures are avoided to help save lives and money,” according to cardiologist Christopher Ellis, M.D., assistant professor of Medicine, who used the resorbable envelope for the first time on Aug. 7.
The CIED is placed below the collar bone in a pocket the physician creates underneath the skin.
Once the device is placed inside the mesh envelope and implanted into the pocket, the antimicrobials are released and the envelope dissolves entirely within about nine weeks.
“The infection protection is still there. It’s nice to know when I go back into the pocket several years from now, I won’t even know it (AIGISRx) was ever in there,” Ellis said.
Research by Ellis and colleagues at Vanderbilt has shown that the AIGISRx Antibacterial Envelope significantly reduced device infections by nearly 90 percent in high-risk patients, compared to patients who did not receive the AIGISRx.
The study, co-authored by Matthew Kolek, M.D., William Dresen, M.D., and Quinn Wells, M.D., was reported in the March issue of PACE.
Nationally, patients with surgical site infections following CIED procedures spend additional time in the hospital and undergo repeat surgical procedures to treat the infection.
These patients experience significant increases in morbidity and mortality, with one-year mortality rates of greater than 25 percent, and three-year mortality of up to 50 percent, depending on device type.
Cardiac device generators typically need to be replaced every five to eight years due to wear and tear, and each time the procedure is performed, the rate of infection increases exponentially, Ellis said.
In addition, there are some patients who are at greater risk of infection due to diabetes, kidney disease and prior device infection.