Lee Hansoo, Thomas Shannon D, Paravastu Sharath, Barber Tracie, Varcoe Ramon L
Department of Vascular Surgery, Prince of Wales Hospital, Sydney, Australia.
Faculty of Medicine, University of New South Wales, Sydney, Australia.
Vasc Endovascular Surg. 2020 Jan;54(1):5-11. doi: 10.1177/1538574419874934. Epub 2019 Sep 10.
High flow rates may develop in arteriovenous fistula (AVF), resulting in clinical syndromes of steal, aneurysmal fistula, or high-output cardiac failure. Various techniques with varying success have been advocated to treat this difficult problem. We present a hemodynamically validated novel banding technique.
We designed a computational fluid dynamic (CFD) model of the native high-flow AVF and tested various juxta-anastomotic venous diameters to determine the effect on AVF blood flow and pressure. We translated this principle in our banding technique, wherein adjustable banding was performed in conjunction with ultrasound-guided brachial artery flow measurement to determine the optimal band diameter. Polyurethane patch was used to fashion the adjustable band. Patient demographics, AVF flow parameters pre- and postintervention, operative intervention, and ultrasound follow-up data were collected prospectively.
Our CFD testing demonstrated that the band diameter needed to achieve optimal distal blood pressure and preserve AVF flow depending on blood pressure, end capillary pressure, venous pressure, and vascular diameters. Five patients subsequently underwent dynamic banding of symptomatic high-flow AVF. Mean brachial artery blood flow rates pre- and postbanding were 2964 mL/min (confidence interval [CI]: 1487-4440 mL/min) and 1099 mL/min (CI: 571.7-1627 mL/min), respectively ( = .01). All patients had symptomatic improvement, and at a mean follow-up of 1 year, this benefit was sustained with no AVF thrombosis or loss.
Adjustable dynamic band using ultrasound-guided brachial artery flow shows promising results in producing accurate AVF blood flow reduction with sustained efficacy in the short term for patients with symptomatic high-flow AVF.
动静脉内瘘(AVF)可能会出现高血流量,从而导致盗血、动脉瘤样内瘘或高输出量心力衰竭等临床综合征。人们提出了各种技术来治疗这一难题,但成功率各不相同。我们介绍一种经过血流动力学验证的新型绑扎技术。
我们设计了一个天然高流量AVF的计算流体动力学(CFD)模型,并测试了各种吻合口附近的静脉直径,以确定其对AVF血流和压力的影响。我们将这一原理应用于我们的绑扎技术中,即在超声引导下测量肱动脉血流的同时进行可调节绑扎,以确定最佳绑扎带直径。使用聚氨酯补片制作可调节绑扎带。前瞻性收集患者的人口统计学资料、干预前后的AVF血流参数、手术干预情况以及超声随访数据。
我们的CFD测试表明,根据血压、末梢毛细血管压力、静脉压力和血管直径,实现最佳远端血压并保持AVF血流所需的绑扎带直径各不相同。随后,5例有症状的高流量AVF患者接受了动态绑扎。绑扎前后肱动脉平均血流速度分别为2964 mL/分钟(置信区间[CI]:1487 - 4440 mL/分钟)和1099 mL/分钟(CI:571.7 - 1627 mL/分钟)(P = 0.01)。所有患者的症状均有改善,平均随访1年时,这种益处得以维持,未出现AVF血栓形成或失功。
对于有症状的高流量AVF患者,使用超声引导肱动脉血流的可调节动态绑扎在短期内能有效准确地减少AVF血流量,并持续发挥疗效,显示出良好的前景。