Development of an Open-source Low-cost Pressure Myography and Cardiac Flow Simulator, HemoLens, for Mechanical Characterization of Native and Engineered Blood Vessels.

Pressure myography, the standard for assessing vascular mechanics and vasoreactivity, is costly ($40,000+), has low throughput, and is limited to static fluid flow. Here, we developed HemoLens, an open-source 3D-printed pressure myography system for ~$700. HemoLens features compact micromanipulators, incremental in-line pressure control, physiological temperature regulation, and modular pulse pressure control between normotensive and hypertensive levels. HemoLen's efficacy was demonstrated by delineation of physiological reactivity and pathological mechanical phenotypes using native mouse arteries and bioprinted acellular scaffolds. Wildtype vessels show greater distention (124.3 vs. 43.07 μm) and increased dynamic compliance compared to diseased vessels. Small diameter (450 μm) collagen-based artery-like scaffolds are FRESH bioprinted to mimic hypertensive vascular stiffening. Engineered hypertensive vessels demonstrate increased burst pressure (464 mmHg) and reduced dynamic compliance reminiscent of diseased arteries. Together, HemoLens lowers the barrier to entry in pressure myography research by serving as a comprehensive low-cost system for native and engineered vessel characterization.