a lot of moving parts going on here, from developing test procedures to confirm the graft is made the same way each time and performs the way it should and testing our new manufacturing electrospinning unit to setting up a quality management system (a process used to track how each device is made) and assessing the device in our current preclinical study. Successful execution of all of these moving parts is essential if we hope to bring the device forward for use in people. You may be asking yourself, “What is a graft and why are they used?” Great questions!
A graft (for a device that is implanted into an artery or vein within the body) is a tubular structure (think of a paper towel roll) that allows blood to pass through it. Grafts can be made from biologic tissue (using a blood vessel harvested from an animal or human that is chemically treated) or from synthetic polymers (i.e. materials that are used to make clothing although much higher quality). I like to think of what we do as high-tech plumbing. In your house, you have different size pipes that transport water to different places. The main line coming into the house is larger to support all of the water needed and the little pipes bring it to the smaller areas in the house. It is the same premise with your arteries (and veins). You have larger arteries like the aortic and thoracic arteries that move a lot of blood from the heart and chest/belly area through the rest of the body to smaller arteries like the femoral and tibial arteries in the legs. Similar to your house, larger pipes usually have no issues with clogging or build-up but smaller pipes can allow debris/gunk to build up. Your arteries perform in a similar fashion. Clogging that occurs in arteries is caused by many different factors such as smoking, poor diet, diabetes and/or unlucky genetics (family history).
Grafts are typically used for three reasons: 1) to re-route the blood around clogged arteries in order to keep blood flowing to other parts of the body, 2) to connect a patient to an implantable device such as an artificial heart and 3) to physically connect an artery to a vein in order to withdraw blood from the body followed by blood infusion back into the body by puncturing the device with two needles. The latter of these reasons describes the process undergone by patients who have kidney disease called hemodialysis, which is the filtering of a patient’s blood to remove impurities since their kidneys are not functioning properly. This process requires an area of the body to insert two large needles, one to an artery to access the blood and one inserted into a vein to bring the blood back. Ideally, the connection between an artery and the vein is made using the patient’s own blood vessels. Since a lot of these patients already have issues with their arteries as previously described, a graft is then used to make this connection.
Our hemodialysis access graft (NuSpun Vascular Graft or NVG) is made from synthetic polymers using our patented electrospinning technology. We believe that our graft will have an advantage over current grafts in that the small fibers comprising the NVG will serve as a scaffold that will allow the body’s own cells to fully integrate into the device, essentially making it more like an artery (see Week 3 blog for more insight into the electrospinning technology). Our NVG also has excellent handling and sewing properties that the surgeons prefer. Lastly, our NVG can also self-seal after the device has been punctured by needles due to the polymers that we use. This property may allow the graft to be accessed quicker than the current devices and may prevent blood from exiting the graft after needle removal, an issue with previous grafts that can result in higher rates of infection. We have a lot of testing to do to prove what we believe will be a superior access graft and look forward to the studies. We believe that if our NVG performs the way we speculate it will, this could really help a lot of kidney disease patients. In addition to this, the device could also be used for the other applications.
One of the ideas we are kicking around is doing a social media live chat in the near future to answer any questions that people may have regarding the technology, what are we working on, what our future plans are, what is our favorite color (put that in there to see if you were paying attention), etc. Let us know the best form of social media for you by answering the survey on the end of the blog! Any questions you might have that we can answer without giving away trade secrets or infringing on our customer’s proprietary research will be open. We would like to hear your thoughts. Chime in on our social media sites!
Have a great weekend everyone and Happy Father’s Day to all of the dads out there!
Matt