## Materials and Methods  
### Experimental Setup  
Analysis of vessels' mechanical behavior required reconstruction of blood hemodynamics in different physiological and pathological conditions. Therefore, an ACM was designed and built for computational projection of vessels' structures under different flow conditions (Figure 1A). The main part of the ex vivo perfusion system was a vessel reactor represented by the transparent, rectangular vessel chamber made of plexy (Figure 1A4) that was able to keep the temperature constant. Temperature was monitored with an installed temperature sensor (Figure 1A9) [22]. Analyzed grafts (Figure 1A6) were placed in a non-commercial fluid mimicking blood's rheological properties, which consisted of 60% distilled water and 40% glycerol (density of 1.2 g cm\({}^{-3}\) and viscosity of 4.8 \(\times\) 10\({}^{-3}\) Pa\(\cdot\)s) [23]. Circulation of non-commercial fluid between the vessel chamber (Figure 1A4) and fluid chamber (Figure 1A11) was provided by a pump (Figure 1A10). To prevent media leakage and allow the graft's interposition, dedicated vessel stabilizers were applied (Figure 1A5). The pulsating character of the flow was achieved by a moving player placed in a stainless-steel corpus called an artificial heart (Figure 1A1) that regulated ejection pressure, ejection volume, and frequency of pulsation. These parameters were controlled by an electrical engine connected to the computer. Therefore, each time, a specified amount of medium supplies the analyzed vessel. Moreover, hemodynamic parameters, e.g., flow/velocity, pressure were monitored with the use of ultrasound flow meters (Figure 1A2) and pressure sensors (Figure 1A3). To set realistic inlet conditions at the inlet of analyzed vessels, the artificial heart was designed and programmed. It mimicked the blood hemodynamic as we previously described [24]. Technical specification of applied sensors included: 0.024-60 L/min \(\pm\) 2% (ultrasound flow meters, made by Bamo), 0-6 bar \(\pm\) 0.5% (pressure sensor, made by Wika), and 0-40 \(\pm\) 0.01 \({}^{\circ}\)C (temperature sensor, made by Wika). Furthermore, to simulate the internal pressure that exists within the abdominal cavity, the vessel chamber was filled with non-commercial fluid mimicking blood at a constant temperature of 37 \({}^{\circ}\)C.  
A dedicated supervisory control and data acquisition (SCADA) system was developed with the use of LabView 2011 software (National Instrument, Austin, TX, USA), and applied for the artificial heart, flow meters, temperature and pressure sensors, and for the control of a vision acquisition system (VAS) (Figure 1B). The VAS system included nine cameras (Figure 1B7) placed on an aluminum circular profile (Figure 1B8), parallel to the floor to provide capability of horizontal movement. The size of an image pixel of the real object was 0.00035 m. To increase the accuracy of vision acquisition, cameras were able to move with 0.17 rad. (10 deg.) steps in both sides at the range of 0.70 rad. (40 deg.) A SCADA was combined with a portable working station Dell Precision M6400 with the following parameters: four core Intel CPU (2.4 GHz), 4 GB RAM (1333 MHz), and 500 GB SSD HD. Figure 1: An artificial circulatory model (ACM) for hemodynamic reconstruction in real and artificial vessels: Part A side view: 1—artificial heart; 2—ultrasound flow meter; 3—pressure sensor; 4—transparent, rectangular, chamber for vessel; 5—vessel stabilizer; 6—analyzed vessel; 7—camera; 8—aluminum circular; 9—temperature sensor; 10—pump; 11—fluid chamber; Part B a vision acquisition system: view from above: 4—transparent, rectangular, chamber for vessel; 6—analyzed vessel; 4; 7—camera; 8—aluminum circular; Part C a real photo of ACM. The flow was reconstructed by means of the following parameters: pulsating character of flow (FP) and different ejection volumes (EV) of non-commercial fluid per one cycle. Initial conditions for the process were as follow: FP: 60, 75, 90, 105, and 120 min\({}^{-1}\); and EV: 70, 85, 100, and 115 mL.