The 3D printing process allows for precise control over the porosity, thickness, and mechanical properties of each layer, which can improve endothelialization (cell lining growth) and therefore enhance long-term patency . The use of different layers, possibly mimicking the natural blood vessel's intima, media, and adventitia, can improve long-term function. It helps to better mimic the compliance mismatch seen in traditional grafts, reducing complications like intimal hyperplasia (narrowing due to cell proliferation) . The synthetic options (Dacron, ePTFE) generally have lower patency rates in smalldiameter grafts (less than 6 mm) due to poor endothelialization and a greater likelihood of thrombosis .