U.O. Nefrologia e Dialisi, Ospedale Sant'Anna, via Napoleona 60, 22100 Como, Italy.
Nephrol Dial Transplant. 2010 Jun;25(6):1943-9. doi: 10.1093/ndt/gfp725. Epub 2010 Jan 11.
Access flow (QA) surveillance is the best method recommended for early stenosis detection, but in native arteriovenous fistula (AVF), the literature is conflicting about the real need for monthly monitoring of QA, as suggested by the K-DOQI Guidelines.
From 1 January 2006 to 31 October 2007 (mean 18.0 +/- 4.9 months), we prospectively followed up 224 patients with monthly AVF monitoring by means of clinical examination and QB stress test (QBST). Suspected malfunctioning AVFs were referred to ultrasound dilution technique (UDT) and imaging techniques (Doppler ultrasonography, angiography), with eventually further percutaneous angioplasty (PTA) or surgical revision.
We observed a good correlation between QBST and QA measurement obtained by the UDT. Patients with positive QBST had a lower QA than negative QBST subjects (433 +/- 203 vs 1168 +/- 681 ml/min, P < 0.0001). Fifty-four out of 224 (24%) patients were selected for possibly malfunctioning AVF. We found no stenosis in 13 out of 54 (24%) patients, inflow stenosis in 29 out of 54 (54%) patients and outflow stenosis in 12 out of 54 (22%) patients. The QBST positive predictive value for inflow stenosis was 76.3%. The interventional radiologist performed 38 PTA procedures in 33 patients (11 PTA per 100 patient-years) and we surgically created 13 new AVF (3.7 per 100 patient-years). Only five thrombosis episodes occurred in five patients during the follow-up (1.5 thromboses per 100 patient-years).
QBST is a simple, low-cost, not time-consuming test, able to select, together with clinical evaluation, malfunctioning AVF with stenosis located specifically in the inflow tract. Our follow-up data demonstrated that it is possible to achieve a low AVF thrombosis rate by adding QBST in an AVF monitoring program, thus reducing the surveillance burden.
流量（QA）监测是早期发现狭窄的最佳方法，但是在天然动静脉瘘（AVF）中，KDIGO 指南建议每月监测 QA，文献对此存在争议。
从 2006 年 1 月 1 日至 2007 年 10 月 31 日（平均 18.0±4.9 个月），我们前瞻性地对 224 例患者进行了每月的 AVF 监测，方法是临床检查和 QB 压力测试（QBST）。疑似功能障碍的 AVF 转介至超声稀释技术（UDT）和影像学技术（多普勒超声、血管造影），最终进一步进行经皮血管成形术（PTA）或手术修正。
我们观察到 QBST 与 UDT 测量的 QA 之间存在良好的相关性。QBST 阳性患者的 QA 低于 QBST 阴性患者（433±203 比 1168±681ml/min，P＜0.0001）。224 例患者中有 54 例（24%）被选择为可能功能障碍的 AVF。在 54 例患者中，我们发现 13 例（24%）无狭窄，29 例（54%）患者存在流入道狭窄，12 例（22%）患者存在流出道狭窄。QBST 对流入道狭窄的阳性预测值为 76.3%。介入放射科医生对 33 例患者（11 例 PTA/100 患者年）进行了 38 次 PTA 手术，我们还手术创建了 13 例新的 AVF（3.7/100 患者年）。在随访期间，仅有 5 例患者发生了 5 例血栓形成事件（1.5 例血栓形成/100 患者年）。
QBST 是一种简单、低成本、耗时少的检测方法，能够与临床评估一起选择特定位于流入道的狭窄功能障碍 AVF。我们的随访数据表明，通过在 AVF 监测方案中添加 QBST，可以实现低 AVF 血栓形成率，从而减轻监测负担。
