Development of novel experimental setup for hands-on cardiovascular biophysics education.

Abstract

A foundational understanding of biophysics and fluid dynamics is critical for comprehending cardiovascular physiological phenomena, yet medical students often struggle with the mathematical complexity. Traditional teaching methods, including in vivo and in vitro experiments, are increasingly being replaced due to ethical concerns, leading to the adoption of in silico models. This study developed a biophysical model simulating the vascular tree using pumps and silicone vessels. Central to the model is a silicone aorta with pressure sensors, immersed in water, and connected to rubber and peristaltic pumps to generate pulse waves. Transparent silicone tubes, decreasing in diameter, mimic the vascular system, while one-way valves regulate flow. Pressure was measured via sensors at key points, with data digitized and visualized in real-time. A 40% ethyl alcohol solution, mimicking blood viscosity, was used. The exercise aimed to teach wave propagation, pressure waveform analysis, pulse wave velocity calculation, and the effects of resistance on wave propagation. Pulse wave propagation was demonstrated with manual compression of the rubber pump generating the input signal. Time delays between pressure waveforms at different sensors were used to calculate pulse wave velocity. Wave reflections were observed as the forward wave traveled to the aortic bifurcation, reflected backward, and then reflected again upon reaching a valve. Reflections were further analyzed with constrictions and added resistance in the system, with careful observation needed to discern the superimposed waves.