InnaVasc Medical, Inc
Puncture-proof vascular graft
InnAVasc Medical, Inc. is a medical device company founded by Duke University surgeons and scientists, which designs and develops products for vascular access for hemodialysis. The Company’s first technology is an arteriovenous graft (AVG) modification that incorporates two multilayer cannulation chambers, with low bleed technology, that are resistant to posterior and sidewall needle penetration and injury.
The InnAVasc arteriovenous graft was designed to reduce the potential for adverse events and device failures associated with repeated vascular access.
Duke physician assistant sees a problem, co-founds startup to solve it
Working as a physician assistant (PA) in vascular surgery at Duke University Medical Center for over 13 years, Shawn Gage has treated thousands of patients with a variety of vascular diseases and complications.
Many such patients have synthetic tubes called arteriovenous grafts surgically implanted in their arms, connecting a vein to an artery for better access to their blood.
At each dialysis session, a nurse or technician inserts two large needles into the graft, one to draw blood into a dialysis machine and one to return cleansed blood from the machine to the body.
“It’s a pretty large needle that they have to stick into a very small space,” Gage explains. “Imagine doing that every other day for years. Unlike your own vessel, it doesn’t heal. That graft turns into Swiss cheese.”
Those repeated needle sticks – known as cannulation in medical parlance – can cause grafts to leak, constrict or collapse, leading to serious complications.
“The more a graft is cannulated, scar tissue and blood byproducts build up within the graft, and the smaller the space becomes, the harder it gets to hit the target,” Gage says. “Frequently the technicians miss or completely pass through the space, causing injuries. That simple interface causes the majority of vascular access problems for dialysis patients.”
It was up to Gage and his clinical partner, mentor, and friend, former Duke vascular surgeon Jeffrey Lawson, M.D., Ph.D., to deal with degraded grafts and their complications.
“Jeff and I would fix these problems on a weekly basis in the operating room,” Gage recalls. “Folks with kidney failure and hemodialysis-access problems are an extremely sick and complicated patient population to care for. We made it our mission to do a better job for these patients.”
A “bullet-proof graft”
The duo knew there had to be a way to prevent these types of graft complications, and in February 2010 they hit on one.
“After a case one day, over lunch in the cafeteria, we literally drew it on a napkin,” Gage recalls.
They sketched a design for a new kind of graft, one with two multi-layered chambers that would self-seal after cannulation while resisting accidental needle punctures through the bottom and sides.
“To date there are no other grafts out there that mitigate these needle-access problems,” says Gage, who refers to the device as “the bullet-proof dialysis graft,” despite its simplicity.
“There are no moving parts or pieces, there are no electronics,” he says. “It’s a very simple idea.”
A simple idea perhaps, but a life-changing one for a then-30-year-old PA who had never planned to do anything but practice medicine. Suddenly Gage was not only an inventor but an entrepreneur too.