Polyurethane-based shape-memory foam embolization system cleared by FDA

Shape Memory Medical (Santa Clara, CA) recently received FDA clearance to market its Impede Embolization Plug in the United States. The device is based on shape-memory polymer (SMP) technology and is designed to reduce or obstruct the rate of blood flow in the vasculature.

Cleared for use in countries in Europe and elsewhere that recognize the CE mark in 2017, the technology is described as a new approach to embolization—inducing or creating a blood clot—by the National Institute of Biomedical Imaging and Bioengineering (NIBIB), which funded the technology. The NBIB is part of the National Institutes of Health.

In embolization procedures, a catheter is threaded through the vascular system, guiding materials that induce clotting in a blood vessel to the treatment site, explains the NIBIB on its website. "Currently, the most commonly used materials for the procedure are coils of platinum or titanium wires that fill the region and induce a clot that stabilizes the blood vessel. However, the wire coils can have subsequent problems, including inflammation, vessel perforation and incomplete healing. These complications can result in patients needing additional treatment to once again repair the blood vessel,” writes the NIBIB.

By contrast, SMP technology uses low-density polyurethane in embolization procedures. The foam formulations and pore sizes can be modified to create materials with a range of properties, explains Shape Memory Medical. After the SMP foam has been created in its primary expanded shape, it is crimped into a catheter-deliverable secondary shape. Following delivery to a blood vessel, for example, the material recovers its primary expanded shape.

The Impede embolization device fills  the vessel more evenly and creates a more uniform blood clot that has been shown in pre-clinical testing to encourage subsequent healing with a single device as opposed to several metallic coils, according to the NIBIB.

Shape Memory Medical
Compressed shape-memory polymer foam on a catheter is shown on the left, beside an image of the fully expanded foam. Image courtesy Shape Memory Medical/National Institute of Biomedical Imaging and Bioengineering.

Impede features proprietary SMP technology developed at Texas A&M University and Lawrence Livermore National Laboratory. Shape Memory Medical continues to develop SMP technology for an expanded range of clinical uses, including neurovascular applications. With both internally developed and licensed technologies, Shape Memory Medical has 26 issued U.S. patents and multiple patents under review globally.