Impact of Duplex Ultrasound Surveillance Program on Patency of Prosthetic Arteriovenous Graft for Hemodialysis: A Single-Center Experience

Background: Arteriovenous prosthetic graft (AVG) is an alternative hemodialysis vascular access
choice; however, its performance is limited by a high rate of thrombosis. The aim of the
study was to compare the long-term secondary patency of AVG in patients undergoing a surveillance
program and the long-term secondary patency of AVG in patients with clinical assessment
of AVG malfunction.
Methods: From 2009 to 2012, all patients with AVG entered in a duplex ultrasound (DUS) surveillance
program (at 3 months and then every 6 months postoperatively) to assess AVG malfunction
and/or stenosis (stenosis >50% and blood flow decrease [<600 mL/min]) and
eventually treated by endovascular revascularization. AVG long-term patency in the surveillance
group was compared with that obtained in a historical control group in which the malfunction was
clinically detected. As secondary end point, the central vein catheter (CVC) placement after AVG
thrombosis was compared in the 2 groups.
Results: Sixty patients were included in the study, 33 (55%) in the surveillance program and 27
(45%) in the historical group. The 2 groups had similar clinical characteristics and follow-up (59,
interquartile range [IQR]: 45 vs. 56 [IQR, 40 months], P ¼ 0.32). Fifteen (45%) AVG malfunctions
were detected in the surveillance group and successfully treated (10 [66.6%] angioplasty
and 5 [33.4%] angioplasty stenting). No malfunction was detected in the historical control group.
By KaplaneMeier analysis, the 5-year secondary patency was significantly higher in the surveillance
group compared with the historical group: 42 ± 13% vs. 9 ± 7%, P ¼ 0.03. By Cox analysis,
the DUS surveillance was a significantly protective factor for AVG thrombosis, otherwise the use
of CVC before the AVG and diabetes mellitus were AVG thrombosis risk factors. The CVC
placement was significantly lower in the surveillance group compared with the historical group
(14.0% vs. 42.2%, P ¼ 0.02).
Conclusions: The DUS surveillance allows a greater secondary patency compared with a clinical
evaluation and reduces CVC placement rate.