not sure if any of these are what you're looking for...
75790: Angiography, arteriovenous shunt (eg, dialysis patient), radiological supervision and interpretation
36145: Introduction of needle or intracatheter; arteriovenous shunt created for dialysis (cannula, fistula, or graft)
G0393/75978: Transluminal balloon angioplasty, percutaneous; for maintenance of hemodialysis access, arteriovenous fistula or graft; venous OR
35476/75978: Transluminal balloon angioplasty, percutaneous; venous
G0392/75962: Transluminal balloon angioplasty, percutaneous; for maintenance of hemodialysis access, arteriovenous fistula or graft; arterial OR
35475/75962: Transluminal balloon angioplasty, percutaneous; brachiocephalic trunk or branches, each vessel
37607: Ligation or banding of angioaccess arteriovenous fistula