Design of an In Vitro Mock Circulatory Loop to Reproduce Patient-Specific Vascular Conditions: Toward Precision Medicine

Patient-specific hemodynamic studies have attracted considerable attention in recent years due to their potential to improve diagnosis and optimize clinical treatment of cardiovascular diseases. Personalized computational models have been extensively investigated as a tool to improve clinical outcomes and are often validated against in vitro experimental data. Replicating patient-specific conditions in vitro is thus becoming increasingly important in cardiovascular research; experimental platforms can not only allow validation of in silico approaches but can also enable physical testing of various intervention scenarios and medical devices. Current experimental approaches suffer from shortcomings regarding personalization and biomimicry. To address some of these limitations, we have designed and developed a novel in vitro platform for the study of complex patient-specific vascular pathologies. This is achieved by using novel tunable three-element Windkessel vasculature simulators and a computer controlled pulsatile pump, coupled with mathematical models and computer routines to calibrate the parameters according to the available clinical datasets. In particular, the vessel inlet flow rate waveform and the afterload resistances and compliances are tuned in order to obtain target systolic and diastolic pressures, and cardiac output (CO) distribution. Pulse frequency (40–70 bpm), CO (2–5 l/min), resistance (0.03–10.6 mmHg s/ml), and compliance (0.07–1 ml/mmHg) values have been tested and the overall reliability of the platform components as well as its computer routines to reproduce controlled physiological conditions demonstrated.