Office-based duplex-guided balloon-assisted maturation of arteriovenous fistulae is feasible, safe and averts nephrotoxic contrast and radiation, a new study presented at the 2010 European Society for Vascular Surgery annual meeting has shown.
The results were presented by Enrico Ascher, Maimonides Medical Center, New York, USA.
“It has been reported that 30–50% of arteriovenous fistulae do not mature by three months post-operation. Recently balloon-assisted maturation with increasingly larger balloons was shown to accelerate maturation. We describe our experience with office- based duplex-guided balloon-assisted maturation and analyse balloon-assisted maturation-induced vein injuries outcome,” Ascher said.
Over seven months the investigators performed 116 duplex-guided balloon-assisted maturations (range 1–8 procedures, mean 4) in 30 patients (21 male, 9 female; mean age 68.2±12.8) with 20 radiocephalic, five brachiocephalic, five brachiobasilic arteriovenous fistulae. There were 66 retrograde vein (57%), 34 ante grade vein (29%) and 16 ante grade arterial (14%) punctures. Balloon sizes (3–10mm) were chosen based on duplex measurements (1–1.5mm larger than minimal vein diameter). Forearm fistulae were dilated to 8mm; arm fistulae to 10mm. Vein injuries were classified based on duplex assessment: class 0, no injury; class 1, intimal flaps; class 2, wall hematoma; and class 3, vein rupture. All patients had post- balloon-assisted maturation duplex scans in a week.
All cases but one (99%) were successful. No injuries were seen in 44 cases (38%); wall haematomas were the most significant injury in 47 cases (41%) and vein rupture in 24 cases (21%). There were 11 vein rupture cases in 36 arm balloon-assisted maturations (31%) as compared to 13 ruptures in 79 forearm balloon-assisted maturations (16%) with p=0.045. Smaller balloons (3–6mm, 60 cases) caused 31 (52%) class 2–3 vein injuries as compared to larger balloons (7–10mm, 55 cases) which caused 40 (73%) class 2–3 injuries with p=0.023. Manual compression was sufficient to stop extravasation in all vein rupture cases. All injuries except for two wall ruptures healed within one week. These two cases formed small (<1cm) pseudoaneurysms which are being observed, Ascher said. Thus far, all 20 patients who needed dialysis following duplex-guided balloon-assisted maturation were successfully treated.
Duplex imaging, Ascher said, identifies the various types of venous injuries and their healing process. “Arm arteriovenous fistulae have more vein ruptures as compared to forearm fistulae. Larger balloons cause more vein wall haematomas and ruptures,” he added.