The flexibility of 3D printing is, quite literally, a key aspect of the research currently being conducted at the Center for Cardiovascular Simulation (CCS) at the University of Texas, Austin. We are constantly marveling at the many applications for this groundbreaking technology, from macro to micro levels, no less. Now, Dr. Michael Sacks’ CCS 
research group is exploring the use of flexible, 3D printed devices that will aid them in treating a range of treatments for cardiovascular disease, particularly when 3D printing is paired with biomechanical computer modeling.
At this stage, the research team is trying to understand the biomechanical function of the cardiovascular system itself, from “the continuum-cellular and micro-fibrous tissue to the entire organ level.” That means they must first have a clearer understanding of the actual mechanical properties of the organic material they are modeling.
3D rendering of a ventricle from CCS
How do various tissues that make up the cardiovascular system function? What are their material properties? Since the 1960s, researchers have been utilizing biaxial testing devices to discern how tissue stretches. To put it simply, they stretch tissue in two different directions and measure the results. Typically, the tissue samples have been 10 x 10 cm square or even larger. However, one of the CCS researchers, John Lesicko, has been conducting biaxial testing on mice, so the tissue samples — and the arteries being tested — are obviously much smaller than those from humans.
Enter CAD and 3D printing. Lisicko and the CCS research team are designing a micro-scale biaxial testing device that can manage much smaller samples — as small as 3 mm x 3 mm square! The device is constructed of 200-micron (one thousandth of a millimeter) diameter stainless steel rods, which stretch the tissue from separate attachment points. The rods cannot touch and must work independently of one another in the sense that they are pulling the cardiovascular tissue in two different directions. The attachment elements required holders set at specific points in the tissue to make the the device work properly.
CCS turned to Potomac, a company that specializes in digital and micro fabrication and uses 3D printing. As the process of developing the miniscule device — the rods and the attachment elements — was ongoing, price was a major concern for the researchers. However, 3D printing and refinement via CAD and in the lab has allowed them to keep costs down in a significant way. The ultimate goal is to create a process of patient-specific modeling using computer modeling and 3D printing for, says CCS, “direct manufacturing of personalized medical devices.”
What do you think about this latest nanotechnology application for 3D printing? Let us know in the CCS Nano 3D Printing forum thread at 3DPB.com.
