University of Pittsburgh

Topograft: Tuning Adhesion at Blood Contacting Device Interfaces

Synthetic vascular grafts fail rapidly in small diameter procedures, such as below-knee grafting, coronary artery bypass, and dialysis access, forcing surgeons to use live vessels harvested from the patient. This results in an additional surgery, increasing costs and recovery time. Furthermore, 20% of patients are unable to provide suitable vessels for use, leaving synthetic grafts as the only option. A long-lasting, safe synthetic graft could eliminate the need for additional surgeries and the accompanying risks.

Description

Topograft is a synthetic vascular prosthetic that uses reversible surface topographic actuation to drive renewal at the fluid/surface interface. At the heart of this technology is the concentrated cyclical infusion of mechanical energy at the foulant/polymer interface that leads to foulant dislodgment and surface renewal, which is useful for removing potential complications such as blood clots. Reversible surface wrinkling in composite polymer multilayers is used as the source of surface topography, but detailed computational and analytical analysis allows the design of tailored surface topographies for specified foulant burdens in diverse industrial and medical applications. Initial studies in a porcine model have shown this concept works in reducing platelet adhesion when compared with smooth static surfaces, like those used in standard vascular grafts, by up to 95 percent. Crucially, Topograft also outlasts traditional grafts, reducing the chance of needing an additional surgery.

Applications

• Cardiac and lower extremity bypass
• Dialysis access surgery (arteriovenous fistula, graft, or catheter)

Advantages

• Eliminates the need for a harvesting surgery
• Lasts longer than other synthetic vascular grafts
• Continually self-cleans foulants such as clots

Invention Readiness

Prototype

IP Status

https://patents.google.com/patent/US20210236700A1