Department of Mechanical Engineering, University of Cincinnati, Cincinnati, Ohio, USA.
Kidney Int. 2012 Apr;81(8):745-50. doi: 10.1038/ki.2011.468. Epub 2012 Feb 22.
Although arteriovenous fistulae are currently the preferred form of vascular access, early failure is a significant problem. Since wall shear stress is thought to play an important role in the pathogenesis of early failure, and this stress varies markedly in different fistula configurations, we assessed the influence of configuration (curved or straight) on longitudinal changes of flow rate and lumen diameter in a porcine fistula model. Fistulae were created in eight pigs between the femoral artery and vein, with each animal having a curved and a straight configuration on opposite sides. Velocity measurements were obtained by ultrasound at the time of surgery and at intermediate time points up to 28 days. Quantification of both the configuration and the internal diameter of the fistulae was determined by CT scans. The overall rate of increased flow during each time interval (0 to 2 days, 2 to 7 days, and 7 to 28 days) was more pronounced with the curved fistulae. Moreover, the luminal diameter of curved fistulae had dilated more from the time of surgery to 28 days as compared to the straight fistulae. Thus, anatomical configuration of fistulae plays a major role in flow-mediated dilatation. Identifying the optimal configuration may result in increased diameter and consequently blood flow, and perhaps reduce the incidence of early failure.
虽然动静脉瘘目前是首选的血管通路形式，但早期失功是一个重大问题。由于壁切应力被认为在早期失功的发病机制中起重要作用，并且这种应力在不同瘘管构型中变化很大，我们评估了构型（弯曲或直）对猪瘘模型中流量和管腔直径的纵向变化的影响。在 8 只猪的股动脉和股静脉之间创建瘘管，每只动物在相对侧具有弯曲和直的构型。在手术时和 28 天内的中间时间点通过超声获得速度测量值。通过 CT 扫描定量评估瘘管的构型和内径。在每个时间间隔（0 至 2 天、2 至 7 天和 7 至 28 天）中，弯曲瘘管的流量增加率总体上更为明显。此外，与直瘘管相比，从手术到 28 天，弯曲瘘管的管腔直径扩张得更大。因此，瘘管的解剖构型在血流介导的扩张中起主要作用。确定最佳构型可能会增加直径，从而增加血流量，并可能降低早期失功的发生率。
