P12: Mechanical Characterization of Synthetic Tissues for Cardiac Surgical Training

Abstract

Background: Synthetic heart models are commonly used for surgical training, especially for complex procedures. However, current models are expensive and poorly mimic heart tissue mechanics and anatomy. 3D printing unconventional materials can produce more realistic models at a more affordable price; therefore, this study investigates the potential of several 3D printed materials as a synthetic tissue for surgical heart models. Methods: Three synthetic cardiac tissues were fabricated: hydrogel samples (3Dresyn SAE1) on a Form2 laser printer, soft polymer samples (3Dresyn SEA10) on a Form2 laser printer, and silicone samples (Dragon Skin Fast 10A) on an Eazao Zero liquid deposition printer. Synthetic tissues were compared to fresh bovine cardiac tissues in terms of puncture resistance, suture retention, and tensile strength using an AEL universal testing machine and 20N PCE Instruments force gauge. Results: There are no significant differences between the mechanical properties of cardiac tissue and the hydrogel-printed SAE1 samples according to ANOVA with a Tukey’s HSD test (Fig1A). There are significant differences between the SEA10 soft polymer sample and cardiac tissue for the puncture and tension tests, but not for the suture retention test (Fig1A). All mechanical test results are significantly different between the 10A silicone and cardiac samples (Fig1A). An example heart is printed with the hydrogel material to demonstrate usability (Fig1B). Conclusion: The 3D printed hydrogel samples better matched the mechanical properties of cardiac tissue than the other printed samples. Although the hydrogel material proved adequate for surgical simulation, other synthetic tissues should be explored to reduce the cost and time of printing, and to better mimic cardiac tissue.