Question: My cardiologist made an incision at a convenient site in the patient’s thorax to reach the arteriovenous fistula the patient developed after birth. They applied clamps on either side of the fistula and cut through the abnormal connection between the vein and the artery. They then repaired each vessel, using sutures or graft material as needed. My cardiologist checked for normal blood flow pattern through the repaired vessel, using Doppler probe. They repaired the incision site with sutures in layers to prevent any hematoma. How should I report this scenario? Montana Subscriber Answer: You should report 35189 (Repair, acquired or traumatic arteriovenous fistula; thorax and abdomen) on your claim. Fistula defined: A fistula is an abnormal passageway between structures such as vessels, vessels and organs, or skin and organs or abdominal cavity.