From KurzweilAI.net: "New research [demonstrates] the capability of tissue-engineered vascular grafts that are immediately available at the time of surgery and are less likely to become infected or obstructed. A surgeon could pull a new human vein off the shelf for use in life-saving vascular surgeries.The bioengineering method of producing veins shows promise in large- and small-diameter applications, such as for coronary artery bypass surgery and for vascular access in hemodialysis. ... This new type of bioengineered vein allows them to be easily stored in hospitals so they are readily available to surgeons at the time of need. Currently, grafting using the patient's own veins remains the gold standard. But, harvesting a vein from the patient's leg can lead to complications, and for patients who don't have suitable veins, the bioengineered veins could serve as an important new way to provide a coronary bypass. ... In this research, scientists generated bioengineered veins in a bioreactor - a device designed to support a biological environment - and then stored them up to 12 months in refrigerated conditions. The bioengineered veins, 3 millimeters to 6 millimeters in diameter, demonstrated excellent blood flow and resistance to blockage in large animal models for up to a year. ... Not only are bioengineered veins available at the time of patient need, but the ability to generate a significant number of grafts from a cell bank will allow for a reduction in the final production costs, as compared to other regenerative medicine strategies. While there is still considerable research to be done before a product is available for widespread use, we are highly encouraged by the results outlined in this paper and eager to move forward with additional study."