Mechanical properties of biodegradable small-diameter chitosan artificial vascular prosthesis.

Initial clinical feasibility with the small-diameter chitosan artificial vascular prosthesis has been reported previously. Here, we present the results of mechanical properties of artificial vascular prosthesis with 2, 3, and 4 mm inner diameter (ID) and compare some of the properties with the native blood vessel of dog femoral artery. Thickness wall measurement demonstrated the average wall thickness of the artificial vascular prosthesis with 2, 3, and 4 mm ID and the native blood vessel of the dog femoral artery with 3 mm ID were 0.54 ± 0.022 mm, 0.71 ± 0.032 mm, 0.79 ± 0.026 mm, and 0.67 ± 0.22 mm (n = 20). Water absorption rate of 226.02% ± 8.17%, 216.13% ± 4.86%, and 205.69% ± 4.34% were obtained from 2-, 3-, and 4-mm-diameter artificial vascular prosthesis (n = 12), respectively. Water osmotic pressure of the 2-, 3-, and 4-mm-diameter artificial vascular prosthesis was 39.25 ± 3.35 mmHg, 34.2 ± 4.54 mmHg, and 28.00 ± 2.72 mmHg (n = 20), respectively. Water osmotic amount of the 2-, 3-, and 4-cm-diameter artificial vascular prosthesis (n = 20) was 4.90 ± 0.47 mL/(min cm(2) ), 5.51 ± 0.21 mL/(min cm(2) ), and 6.24 ± 0.71 mL/(min cm(2) ), respectively. The ruptured stretching rate of the artificial vascular prosthesis (n = 20) with 2, 3, and 4 mm ID and the native blood vessel was 1.59% ± 0.14%, 1.99% ± 0.24%, 2.52% ± 0.21%, and 32.16% ± 2.15%, respectively. The longitudinal tensile strength of the artificial vascular prosthesis (n = 20) with 2, 3, and 4 mm ID and the native blood vessel was 8.58 ± 1.98 N, 19.75 ± 4.07 N, 22.92 ± 3.85 N, and 18.76 ± 2.05 N, respectively. The suture retention of the artificial vascular prosthesis (n = 20) with 2, 3, and 4 mm ID and the native blood vessel in dry condition is 5.80 ± 0.51 N, 7.01 ± 0.32 N, 8.49 ± 0.56 N, and 7.92 ± 0.39 N, respectively. The suture retention of the artificial vascular prosthesis (n = 20) with 2, 3, and 4 mm ID in wet condition is 3.87 ± 0.43 N, 4.73 ± 0.37 N, 5.63 ± 0.36 N, and 7.92 ± 0.39 N, respectively. The compliance of the artificial vascular prosthesis with 2, 3, and 4 mm ID and the native blood vessel was 6.5% ± 2.6%/100 mmHg, 5.2% ± 1.5%/100 mmHg, 4.7% ± 1.3%/100 mmHg, and 10.3% ± 2.3%/100 mmHg, respectively. The data reported here fulfill the quality requirement of clinical use of this kind of biodegradable small diameter artificial vascular prosthesis.