Venous Outflow Options for AVG Loop Grafts
For an arteriovenous graft (AVG) loop configuration, multiple veins can serve as venous outflow, with the specific choice depending on anatomical location and vessel availability. 1
Forearm Loop Graft Venous Outflow Options
The median antecubital vein is the primary venous outflow target for forearm loop grafts. 1 Additional forearm loop options include:
- Proximal or distal cephalic vein 1
- Basilic vein at the elbow level 1
- Brachial vein (deep vein system) when superficial veins are inadequate 2, 3
Upper Arm Loop Graft Venous Outflow Options
For upper arm loop configurations, the basilic vein at the upper arm level is commonly used. 1 Other upper arm options include:
- Basilic vein or deep brachial vein just above the elbow in reverse-loop configurations 2
- Axillary vein for more proximal grafts 1
- Proximal axillary vein via infraclavicular approach when preserving distal sites 4
Strategic Considerations for Vein Selection
Prioritize superficial veins (cephalic, basilic) before deep veins (brachial, axillary) to preserve future access sites. 1 The guidelines emphasize that:
- Using smaller, more peripheral vessels preserves proximal sites for future access creation despite potentially higher thrombosis rates requiring treatment 1
- The two preferred graft site types are the antecubital loop graft and upper-arm curved graft 1
- Grafts using larger proximal vessels should be avoided despite better initial flow and patency, as they limit future placement options 1
Alternative Configurations When Standard Veins Unavailable
When superficial veins are inadequate, the brachial vein (deep system) provides reliable venous outflow for forearm loop grafts. 3 This brachial-brachial configuration achieved:
- Secondary patency rates of 76.3% at 12 months and 54.6% at 36 months 3
- Median cannulation time of 3.4 weeks 3
- Primary failure rate of only 7.6% 3
For patients who have exhausted upper extremity options, anterior chest wall grafts connecting the axillary artery to ipsilateral or contralateral axillary veins represent viable alternatives. 5
Critical Pitfall to Avoid
Femoral vein placement should be avoided when possible, as it is associated with proximal venous stenosis that may be problematic later in kidney transplant recipients. 1