ASTM International Committee F04 on Medical and Surgical Materials and Devices is developing a proposed new standard that will help the medical device industry with the measurement and reporting of vascular stent radial stiffness and strength. The proposed standard, WK15227, Test Methods for Radial Stiffness and Strength of Balloon Expandable Stents, is under the jurisdiction of Subcommittee F04.30 on Cardiovascular Standards.
 
“Vascular stents are commonly used as a minimally invasive way to treat stenosis in arteries and improve blood flow to the heart, kidneys, brain and legs,” says Kenneth J. Cavanaugh, Ph.D., co-chair of Task Group F04.30.06 on Endovascular Device Test Methods. “Due to the challenging service environment that stents face in vivo, the radial stiffness of a stent is critical to its function of keeping the arteries open and eliminating abrupt closure.”
 
According to Cavanaugh, standard measurements and reporting methods of a stent’s radial stiffness both assist industry in the development of new stent designs and allow regulatory authorities to better evaluate these designs.
 
“WK15227 will serve as a tool for developers of a new stent platform in designing, qualifying and validating new products,” says Cavanaugh. “In today’s challenging stent market, developers can use tailored standards developed by ASTM International to help bring to the market high-quality products that will better serve the community. The proposed standard will be used to support submissions to regulatory agencies or internally to compare new products to existing products.”
 
In addition, Cavanaugh says that the development of a standardized method for radial stiffness and strength assessment may indirectly help to improve understanding of the causes of late stent thrombosis. There is some evidence that this often-fatal coronary event is associated with stent malapposition, which is often the result of insufficient radial stiffness or strength.
 
Cavanaugh notes that the participation of new members is always welcome in Subcommittee F04.30 and the task group working on WK15227. While the task group has traditionally focused on the development of standards for vascular stents, it is also interested in developing test methods for other endovascular devices, such as aortic aneurysm endovascular grafts, embolic protection devices and inferior vena cava filters. “We would like to encourage participation from individuals experienced in the development and evaluation of all endovascular devices or who want to develop test methods for these devices,” says Cavanaugh.

For further technical information, contact Kenneth J. Cavanaugh, U.S. Food and Drug Administration, Rockville, Md. (phone: 240/276-4141; kenneth.cavanaugh@fda.hhs.gov). Task Group F04.30.06 will meet in October in Rockville, Md. For Committee F04 membership or meeting information, contact Daniel Schultz, Technical Committee Operations, ASTM International (phone: 610/832-9716; dschultz@astm.org).

Release #7724