Resin helps make heart surgery tool

A Sabic Innovative Plastics product story

Edited by the Engineeringtalk editorial team Feb 27, 2006

Polycarbonate resin helps California company make paddle of atrial depressor for device reliability and biocompatibility in minimally invasive mitral valve repair and replacement procedures.

Estech has introduced a surgical device that uses GE's hemocompatible Lexan HPM 1914 polycarbonate resin.

California-based Estech makes cardiac surgery devices, and selected the GE material for the paddle of its single-use Clearview MV Atrial Depressor to help achieve a high level of device reliability and biocompatibility in minimally invasive mitral valve repair and replacement procedures.

The resins provide the typical strength of polycarbonate as well as capabilities that provide improved hemocompatibility, reduced protein binding, improved low temperature ductility and the potential for improved flow and release.

"We consider Lexan HPM resin to be state of the art," said Mike Banchieri, Senior Engineer for Estech.

"The strength of this material gives us confidence that our device will perform reliably during critical heart surgeries, and its hemocompatibility goes well beyond the properties of ordinary polycarbonate to improve patient safety".

"Another important benefit is Lexan HPM resin's compatibility with gamma sterilisation, which helps us speed up production by avoiding the need for lengthy EtO sterilisation".

The depressor, which was introduced in January 2006 at the Society of Thoracic Surgeons' Annual Meeting in Chicago, is a single-use, sterile device that provides exposure of the mitral valve via a paddle and a malleable shaft for retraction of the posterior atrial wall.

The device has an integrated suction channel for clearing the atrium of fluid during minimally invasive heart valve surgery.

By providing a clear field of view in a confined space, the depressor helps surgeons repair or replace the mitral valve accurately and more easily.

The resin enabled Estech to improve on an earlier, reusable version of the device, which was made of stainless steel and required separate steps to attach the suction channel.

The use of the GE material enabled part integration for simpler preparation and operation, reduced weight, and elimination of reprocessing procedures, repairs and the risk of lost parts.

The Lexan HPM resins, which have been commercially available for about six months, are highly ductile, impact-modified polycarbonate copolymers suitable for healthcare applications involving direct blood contact or potential protein interaction.

The resins provide biocompatibility, good property retention following gamma, steam autoclave (at 121C) and EtO sterilisation, as well as resistance to typical healthcare chemicals.

These transparent materials are also available in white.

"GE is investing significant resources to address the changing needs of the healthcare industry, including the trend towards less-invasive surgeries that demand specialised medical devices such as Estech's new depressor," said Clare Frissora, Market Director for Healthcare at GE Plastics.

"Innovative resins like our Lexan HPM grades give manufacturers the tools to create designs that help healthcare providers improve patient safety and surgical outcomes, and enhance speed of procedures".