P201
DISTAL ARTERIOVENOUS FISTULA (AVF) FAILURE. RISK FACTORS
Abdulnabi, K1, Lyon, P1, Denham, N1,Khalil,A1, Howse, M1,Anijeet, H1,Rylands, I2, Alexander,
J1, Pai, P1, Powell, S1, Ridgway, D1.
1The Royal Liverpool Hospital, 2Edge Hill University
OBJECTIVE:
(NICE) and (KDIGO) still recommend that distal AVF creation should be attempted first before
attempting more proximal. It is reported that fistulae using radial arteries with diameters smaller than
1.5 mm were unlikely to be usable for dialysis. It was proposed that a minimal arterial diameter
threshold of 2.0 mm is required for fistula construction.The aim of this retrospective sub analysis of
distal AVF is to study risk factors associated with AVF failure.
METHODS: Retrospective data analysis on 64 distal AVF was performed on prevalent
haemodialysis patients undertaken at a tertiary renal centre.
RESULTS: Age is 60±17 ( 25-90), male: female = 2: 1
Brachial ,Radial artery size and flow on venous mapping prior to AVF formation
FAILED
AVF
N
Mean
Std. Deviation
(B)Arterial flow on venous
mapping ml/min
No
13
73.15
41.06
Yes
16
48.69
23.09
(R)Arterial flow on venous
mapping ml/min
No
12
8.42
3.34
Yes
12
7.33
2.31
(B)Arterial diameter on venous
mapping, mm
No
33
4.74
0.93
Yes
24
3.94
0.89
No
37
2.45
0.58
distal (R)Arterial diameter on
venous mapping, mm
Yes
27
2.02
0.54
There is significant correlation between radial artery size and AVF failure (p<0.001).
p
0.7
0.37
0.002
0.004
Radial artery calibre <2.2mm, on pre op venous mapping, is associated with cumulative AVF failure
of (58%), primary failure at 3 months of (48%) and at 1 year of (52%) compared to 27%, 21% and
27% for calibre ≥2.2. Immaturity was the cause of failure in 67%; p<0.05, OR= 3 (1-10).
Assisted 3 month distal AVF primary failure in patients with PMH of AVF failure was 80% (12/15),
compared to only 20% (10/49) in those with no previous fistulae failure; p=0.00005,OR=16 (4 -66).
Multivariate analysis shows that Radial artery size (p<0.02), Brachial artery size (p<0.03) to be
associated with forearm AVF failure. Hypercoagulable state (p=0.007) Female gender (p=0.03) and
Aspirin 75mg (0.04) and PMH of fistula failure (p=0.04) were associated with 3 month primary
failure. (OR= 42, 1.6, 9.9, 2.3 respectively)
Warfarinisation, PVD, HTN, heart failure, Diabetes or CVA didn’t show any statistical significance.
CONCLUSION:
Forearm AV fistulae should be avoided in patients with radial artery of less than 2,2mm.especially in
the presence of hypercogulable state and past history of AVF failure. Pharmacological therapy plays
no role in reducing distal AVF failure.