Since autologous grafts are harvested from the patient's own body, a separate surgery is required. This increases the likelihood for complications. Disadvantages associated with current synthetic grafts include thrombogenicity, poor elasticity, high inflammation rates and low compliance, all of which can lead to vessel re-closure. Furthermore, synthetic grafts have a minimum inner diameter of 6mm. This is often larger than desired, but is determined by the material. Thus there is a need for a vascular graft that can overcome the current limitations associated with autologous and synthetic grafts.

INNOVATION:  UCLA researchers have designed a thin film metal alloy vascular graft with potential use in various vascular diseases. The metal alloy is unique in that its inherent shape-memory property allows it to retain its original shape and integrity after physical manipulation. This could allow for the delivery of vascular grafts via a catheter.

Thin film metal alloys have demonstrated a clear advantage over Gore-Tex®-based implantable devices. They have proven to be non-toxic, biocompatible and non-thrombogenic. The investigators are looking to develop small diameter vascular grafts (<6mm) using the technology. Small diameter grafts would increase the number of applications in which grafts could be used.

POTENTIAL APPLICATIONS 

• This technology could be used in the ~1.4 million surgical operations requiring arterial prostheses annually.
• Metal alloy vascular grafts with diameters less than 6mm could be useful in various surgeries. For example, bypass grafts for peripheral arterial and venous diseases could be made using the thin film metal alloy technology.
• The technology could be used to develop aortopulmonary shunts for pediatric and neonatal patients.

ADVANTAGES

• The thin film metal alloy vascular graft eliminates the need for harvesting healthy veins and arteries from patients. This will help to reduce complications due to harvesting.
• The non-thrombogenic property of the metal alloy is an inherent improvement over current synthetic grafts.
• Thin film metal alloy grafts improve upon current limitations of synthetic grafts including poor elasticity, high risk of inflammation and low compliance.
• Synthetic grafts with a diameter smaller than those currently available (6mm) can be developed with thin film metal alloy technology.
• The shape-memory property of the metal alloy allows the device to be compressed and still return to its original shape.

Reference: UCLA Case No. 2005-600