Jan Malik, Presenter: Nothing to Disclose

Jaroslav Kudlicka, Abstract Co-Author: Nothing to Disclose

The patency of arteriovenous grafts (AVG) for hemodialysis is mostly limited by stenoses. They decrease the blood flow, with the risk of dialyzed blood recirculation and of thrombosis with access failure. Some risk factors for shorter AVG lifespan are already known and include diabetes mellitus, history of repeated interventions and others. Identification of further risk factors could identify subjects, which would profit from AVG surveillance programs. We hypothesized that  abnormal ultrasound (US) finding just after AVG creation would determine such subjects.

We examined our AVG subjects within 40 days after AVG creation and followed them up for years with US surveillance every 3 months and recorded interventions. According to US finding the AVGs were divided into three groups: 1. normal finding, 2. non-significant stenosis and 3. hemodynamically significant stenosis. The primary endpoint of the study was cumulative AVG patency that is the time interval since creation until final AVG loss. The data were analyzed by Log-rank (Mantel-Cox) test and Student’s t-test and visualized by survival graphs.

Overall, we included 360 AVGs. Median follow up was 565 days. Normal ultrasonographic finding was in 265 cases (78%), non-significant stenosis was found in 46 (13%) cases and significant stenosis in 29 (9%) cases. The longest cumulative patency was observed in patients, which had normal US findings at inclusion and it was significantly longer than in non-significant stenosis (p = 0.04); the latter group had longer patency than significant stenosis patients (p=0.03). Survival of normal findings and nonsignificant stenosis groups differed significantly after 443 days (p=0.03) in favor of normal findings as well as the mean time of the first intervention [(334 vs. 147 days after AVG creation (p<0.0001), respectively]. Non-significant and significant stenosis groups differed in AVG survival after 453 days (p=0.04) in favor of the former group, which also had longer intervention/free interval (147 vs. 82 days, p=0.03).

Early US examination of AVGs identifies subjects at higher risk of access loss. Further research is needed to find out if more frequent surveillance or re-do surgery could prolong the AVG lifespan of these patients.

The presence of any stenosis at early ultrasonography of AVGs is associated with poorer prognosis despite its successful therapy

Malik, J, Kudlicka, J, Ultrasound Examination after Creation of Dialysis Arteriovenous Grafts Forecasts Their Lifespan.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14012543.html