Table 4.
Examples of mechanical properties and testing parameters reported on blood vessel substitutes studies.
| Testing method | Sample type, geometry | Preconditioning | Deformation rate | Data analysis methoda | Elastic modulus (MPa) | SB or BP | EB | C (%/100 mmHg) | Ref |
|---|---|---|---|---|---|---|---|---|---|
| 1. Natural biomaterials | |||||||||
| CS | Collagen gel, cylindrical | Three cycles: 0–2% strain | 0.2 mm/s | 15–30% strain, linear regression | 0.010 | – | – | – | [32] |
| T | Square-section toroidal | 0.040 | 0.005 MPa | – | – | ||||
| T | Collagen gel, ring | Ten cycles: 0–5% strain at 1%/s | 5%/s | Slope of stress-strain linear region curve before break | IEM: 0.043 EEM: 0.012 |
– | – | – | [41] |
| SR | 1 step of 10% strain, 2.5 min relax. | Viscoelastic mathematical models | 0.046 | – | – | – | |||
| T | Collagen gel with SMCs, ring | Three cycles: 0–20% of EB | 0.2 mm/s | 10–20% strain, slope | 0.142 | 0.058 MPa | ~50% | [45] | |
| T | Collagen gel with FBs, ring | Three cycles: 0–20% of EB | 0.2 mm/s | 25–75% of the SB, best fit regression | 0.018 | 0.0053 MPa | – | – | [50] |
| SR | – | 6 steps of 15% EB, 6 min relax. | Viscoelastic mathematical models | IEM: 0.0097 EEM: 0.00166 |
– | – | – | ||
| SR | Collagen gel with SMCs, ring | Stretched to a preload of 30 mN | 5%/s, 6 steps of 10% strain, 10 min relax. | Slope (least-square method) of the stress-strain curve linear region | IEM: 0.030 EEM: 0.012 |
– | – | – | [49] |
| C | Tubular | – | 20 mL/min, 20–120 mmHg, 1 Hz | Eq. (16) | – | – | – | 19 | |
| SR | Collagen gel and recombinant elastin with FBs, ring | Stretched to 5% strain | 5%/s | 25% strain, viscoelastic mathematical models | IEM: 0.056 EEM: 0.024 |
0.026 | 70% | – | [52] |
| T | Electrospun recombinant elastin, dogbone | – | 2 mm/s | 10–30%, linear regression | 0.15 (long) 0.15 (circ) |
0.38 MPa (long) 0.34 MPa (circ) |
75% (long) 79% (circ) |
20.2 | [38] |
| BP | Tubular | – | 100 mL/min | Burst point | – | 485 mmHg | – | – | |
| CS | Dextran and gelatin gel, cylindrical | – | 0.1 mm/min | 0–20% strain, slope | 0.051 | 0.031 | 47% | – | [33] |
| DMA | ring | – | 5% strain amplitude, 0.1–10 Hz | – | E′: 0.040 E′′: 0.004 |
– | – | – | |
| T | Electrospun silk, ring | – | Three incremental cycles at 0.2 mm/s | 25–75% of the yield stress | 2.45 | 2.42 MPa | – | – | [42] |
| BP | Tubular | – | Burst point | – | 811 mmHg | – | – | ||
| BP | Self-assembled construct, tubular | – | 4 mL/min, 80–120 mmHg | Burst point | – | 1075 mmHg | – | – | [55] |
| C | – | Eq. (16) | – | – | – | 4.6 | |||
| 2. Synthetic biomaterials | |||||||||
| T | PEUU scaffold, rectangular | 10 cycles: 0–20% strain | 10 mm/min | Strain level at physiological pressure | 1.8 (long) 1.4 (circ) |
21.1 MPa (long) 8.3 MPa (circ) |
5.6 (long) 5.3 (circ) |
– | [35] |
| BP | Tubular | – | 100 mL/min | Burst point | – | 2300 mmHg | – | ||
| C | 100 mL/min, 80–120 mmHg | Eq. (16) | – | – | – | 4.6 | |||
| T | Electrospun PEUU | – | 10 mm/min | – | 2.5 | 8.5 MPa | 280% | – | [36] |
| T | PLA/PCL tube, tubular and ring | Pretension of 0.5 N | 50 mm/min | 0–5%, slope | 59.6 (long) 46.4 (circ) |
21.3 MPa (long) 11.8 MPa (circ) |
28.0% (long) 212.6% (circ) |
– | [43] |
| BP | Rectangular | Preload of 0.1 N | Burst point | – | 37 038 mmHg | – | – | ||
| C | Tubular | – | 100 mL/min, 1 Hz, (50–90, 80–120, 110–150) mmHg | Eq. (16) | – | – | – | 1.70 | |
| T | Electrospun PCL, dogbone | – | 5 mm/min | 0–10% strain | 3.49 (long) 3.95 (tang) |
1.25 MPa (long) 1.63 MPa (tang) |
– | – | [37] |
| BP | Tubular | 20 mL/min | Burst point | – | 500–1800 mmHg | – | – | ||
| T | Electrospun PCL, tubular | – | 10 mm/min | – | – | 4.1 MPa | 1092% | – | [44] |
| BP | – | 0.1 mL/min | Burst point | – | 3280 mmHg | – | – | ||
| BP | Electrospun PCL, tubular | – | According to ISO 7198 | Burst point | – | 684 mmHg | – | – | [56] |
| C | – | 80–120 mmHg | – | – | – | 5.3 | |||
CS, compression testing; T, tensile testing; SR, tensile stress relaxation testing; IEM, initial elastic modulus; EEM, equilibrium elastic modulus; ES–TIPS, electrospinning–thermally induced phase separation; tang, tangential; SMCs, smooth muscle cells.
a
Data analysis method includes the strain range used and the method for calculation of the mechanical properties.