Palmaz F, Sprague E, Palmaz J C
Cardiovascular and Interventional Radiology Section, University of Texas Health Science Center at San Antonio 78284-7800, USA.
J Vasc Interv Radiol. 1996 Sep-Oct;7(5):657-63. doi: 10.1016/s1051-0443(96)70824-2.
To evaluate the performance characteristics of 3-mm and 6-mm polytetrafluoroethylene (PTFE) grafts after radial dilation comparable to their use in endovascular applications.
PTFE conduits with 3- and 6-mm internal diameters were radially expanded three, four, and five times the original diameter with angioplasty balloons. Internal diameter, outer diameter, wall thickness, radial and longitudinal shortening, internodal distance, radial and longitudinal tensile strength, water entry pressure, and suture retention strength were measured and compared with nondilated samples.
After dilation, the diameter of the 3- and 6-mm PTFE conduits recoiled approximately 23%, and the length shortened insignificantly. The wall thickness decreased to approximately half, and the internodal distance did not change. Porosity decreased as evidenced by a slight increase in the water entry pressure. Longitudinal and radial tensile strength, as well as suture retention strength, were decreased.
Dilation of PTFE graft, as used in endovascular applications, by three to five times results in moderate elastic recoil. This needs to be taken into consideration if the material is used without a supporting inner stent. Because of the absence of significant change in porosity, perigraft fluid collections are not likely to occur. Significant decrease in suture retention strength after dilation poses a risk of localized tear and potential procedure failure.
评估3毫米和6毫米聚四氟乙烯（PTFE）移植物在径向扩张后的性能特征，这与它们在血管内应用中的情况相当。
使用血管成形术球囊将内径为3毫米和6毫米的PTFE导管径向扩张至原始直径的三、四和五倍。测量内径、外径、壁厚、径向和纵向缩短、节间距离、径向和纵向拉伸强度、进水压力以及缝线保留强度，并与未扩张的样本进行比较。
扩张后，3毫米和6毫米PTFE导管的直径回缩约23%，长度缩短不明显。壁厚降至约一半，节间距离未改变。进水压力略有增加，表明孔隙率降低。纵向和径向拉伸强度以及缝线保留强度均降低。
用于血管内应用的PTFE移植物扩张三至五倍会导致适度的弹性回缩。如果在没有支撑性内支架的情况下使用该材料，这一点需要考虑。由于孔隙率没有显著变化，不太可能发生移植物周围液体聚集。扩张后缝线保留强度显著降低会带来局部撕裂和潜在手术失败的风险。
