Development of an Open-source Low-cost Pressure Myography and Cardiac Flow Simulator, HemoLens, for Mechanical Characterization of Native and Engineered Blood Vessels (CAD, Build Guide, and Software)

Introduction: To overcome the high cost and limited dynamic testing capabilities of current myography systems, we developed HemoLens, a low-cost (~$740) platform enabling both static and dynamic vascular analysis to broaden research accessibility. This system provides a critical tool for evaluating vascular function and engineered tissues under physiologically relevant conditions.

Here we provide the CAD design files, BOM, build guide, and software to construct and run HemoLens. We also include predefined build plates and arrangements for 3D printing of plastic components on a BambuLabs X1C or similar 3D printer. All componets were either printed from standard PLA or PETG. Details are described in the manuscript methods and incorperated into the build plate .3mf project files. 

The Arduino code enables dual flow through pressure sensing, control for peristaltic pumps, stepper motor driver using UART/serial control, and dynamic pulse pressure adjustment for beat frequency simulation.  This can be adjusted and customized to meet the users needs. Python code allows for streaming and recording of pressure sensor data without any computational overhead for high speed application. 

This body of work is Published in Device. For more detailed methods and information visit the DOI for the manuscript or www.ShiwarskiLab.com for open-source designs, 3D models, and links to the publication. 

Published Abstract: 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.