Snyder Alexandra E, Sandridge Jada K, Nordmoe Adeline E, Main Evan N, Bowlin Gary L
Department of Biomedical Engineering, The University of Memphis, Memphis, TN, USA.
J Bioact Compat Polym. 2024 Nov;39(6):455-466. doi: 10.1177/08839115241262038. Epub 2024 Jun 17.
Cardiovascular disease, arteriosclerosis, is characterized by the thickening of blood vessel (arteries) walls restricting blood flow and is a global health problem. One treatment option is a surgical procedure utilizing an autologous or synthetic vascular graft to bypass or replace the diseased arterial segment. The goal of this study was to fabricate and mechanically characterize near field electrospun bioresorbable vascular grafts with a fibrous architecture that mimics the arterial extracellular matrix. Polydioxanone vascular constructs with circumferential fiber alignment angles of 15°/75° and 30°/60° (0° representing circumferential fiber alignment) were fabricated using a custom built near-field electrospinning (NFES) system. The vascular construct mechanical properties were compared to the saphenous vein (SV) and internal mammary artery (IMA) through longitudinal and circumferential uniaxial mechanical testing, suture retention, and burst pressure evaluations. The results demonstrated that the 15°/75° templates were closest to mimicking the native vessel target properties as compared to the 30°/60°; however, neither of the vascular template designs achieved or exceeded all the target values. For the ultimate tensile strength, both the constructs met the SV value on the circumferential axis (2.61 MPa) and the IMA value on the longitudinal axis (4.3 MPa). In terms of suture retention, the 15°/75° template was the only construct that was in the IMA and SV targeted range of 138-200 gf. Finally, the burst pressure testing results indicated that neither of the vascular constructs achieved the level of the SV or IMA (1600-3196 mmHg), however, the 15° constructs were within the lower error of the SV. In conclusion, with further design modifications, NFES constructs have demonstrated promise as small-diameter vascular grafts by mimicking native arterial architecture and mechanical properties.
心血管疾病，即动脉硬化，其特征是血管（动脉）壁增厚，限制血液流动，是一个全球性的健康问题。一种治疗选择是采用自体或合成血管移植物进行外科手术，以绕过或替换患病的动脉段。本研究的目的是制造具有模仿动脉细胞外基质纤维结构的近场电纺生物可吸收血管移植物，并对其进行机械特性表征。使用定制的近场电纺丝（NFES）系统制造了圆周纤维排列角度为15°/75°和30°/60°（0°代表圆周纤维排列）的聚二氧六环酮血管构建体。通过纵向和圆周单轴力学测试、缝线保留力和爆破压力评估，将血管构建体的力学性能与大隐静脉（SV）和乳内动脉（IMA）进行了比较。结果表明，与30°/60°的模板相比，15°/75°的模板最接近模仿天然血管的目标特性；然而，两种血管模板设计均未达到或超过所有目标值。对于极限拉伸强度，两种构建体在圆周轴上均达到了SV值（2.61MPa），在纵轴上达到了IMA值（4.3MPa）。在缝线保留力方面，15°/75°的模板是唯一处于IMA和SV目标范围138-200gf内的构建体。最后，爆破压力测试结果表明，两种血管构建体均未达到SV或IMA的水平（1600-3196mmHg），然而，15°的构建体在SV的较低误差范围内。总之，通过进一步的设计改进，NFES构建体通过模仿天然动脉结构和力学性能，已显示出作为小直径血管移植物的潜力。
