During post-operative assessment of a hemodialysis access graft, which finding is most directly associated with graft thrombosis due to stenosis?

• A. Graft Thrombosis - Stenosis
• B. Flow Volume
• C. Arterial Steal
• D. Venous Outflow

Answer: (A)

Stenosis in the graft or its anastomosis is the primary trigger for thrombosis in a hemodialysis access. When a narrowing develops, flow becomes restricted and turbulent, promoting stasis and clot formation within the graft. The most direct finding linking thrombosis to this lesion is the presence of graft thrombosis in the context of a documented stenosis—the sequence from narrowing to clot is what drives the failure.

Other findings can be related but don’t establish that direct cause-and-effect. For example, flow volume can drop with stenosis, but it’s the actual thrombus forming due to the stenotic lesion that ties them together. Arterial steal and venous outflow issues describe separate complications or consequences and aren’t the direct link to thrombosis caused by stenosis. In practice, imaging would look for a focal stenosis with high velocity and post-stenotic changes, plus any intraluminal thrombus if thrombosis has occurred.