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Official Description

Thrombectomy, open, arteriovenous fistula without revision, autogenous or nonautogenous dialysis graft (separate procedure)

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The procedure described by CPT® Code 36831 refers to an open thrombectomy performed on an arteriovenous (AV) fistula, which is a surgical connection between an artery and a vein. This procedure is necessary when a thrombus, or blood clot, forms within the AV fistula, leading to occlusion and impaired blood flow. The thrombectomy is conducted without any revision of the fistula itself and can involve either autogenous (using the patient's own tissue) or nonautogenous (using synthetic materials) dialysis grafts. The process begins with an incision made over the AV fistula, allowing the surgeon to access the affected blood vessels. Once exposed, vessel loops are strategically placed to control blood flow, enabling the surgeon to safely open the artery, vein, or graft to remove the thrombus. Techniques such as applying arterial back pressure or manual massage may be employed to facilitate the expulsion of the clot. After the thrombus is successfully removed, a completion angiography may be performed to verify that the clot has been entirely cleared and that the AV fistula remains patent, ensuring proper function for future dialysis treatments.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The open thrombectomy procedure described by CPT® Code 36831 is indicated for patients who have developed a thrombus within an arteriovenous (AV) fistula, which can lead to occlusion and hinder effective blood flow necessary for dialysis. The following conditions may warrant this procedure:

  • Thrombus Formation The presence of a blood clot within the AV fistula that obstructs blood flow.
  • Impaired Dialysis Access Difficulty in accessing the AV fistula for dialysis due to occlusion caused by the thrombus.
  • Symptoms of Ischemia Clinical signs indicating reduced blood flow, which may include swelling, pain, or discoloration in the extremities.

2. Procedure

The open thrombectomy procedure involves several critical steps to ensure the successful removal of the thrombus from the AV fistula. The following procedural steps are outlined:

  • Step 1: Incision An incision is made over the site of the AV fistula, allowing access to the underlying blood vessels. This incision is crucial for exposing the artery and vein involved in the fistula.
  • Step 2: Exposure of Blood Vessels Once the incision is made, the surgeon carefully dissects the tissue to expose the artery, vein, and any associated graft. This step is essential for visualizing the thrombus and the surrounding structures.
  • Step 3: Placement of Vessel Loops Vessel loops are placed both proximal and distal to the thrombus. This technique helps to control blood flow during the procedure, ensuring that the area remains clear for the thrombectomy.
  • Step 4: Opening the Vessel The surgeon then opens the artery, vein, and/or graft to directly access the thrombus. This step is critical for the removal of the clot.
  • Step 5: Thrombus Removal The thrombus is removed through direct exposure. The physician may utilize techniques such as applying arterial back pressure or manual massage to assist in expelling the clot from the vessel.
  • Step 6: Completion Angiography After the thrombus has been removed, a completion angiography may be performed. This imaging technique is used to confirm that the entire clot has been successfully cleared and that the AV fistula is patent, ensuring it is ready for use in dialysis.

3. Post-Procedure

Following the open thrombectomy procedure, patients may require monitoring for any signs of complications, such as bleeding or infection at the incision site. The recovery process typically involves assessing the functionality of the AV fistula to ensure that blood flow is restored adequately. Patients may also be advised on care for the incision site and any restrictions on physical activity during the initial recovery phase. Regular follow-up appointments may be scheduled to evaluate the patency of the AV fistula and to ensure that the patient can resume dialysis treatments without further complications.

Short Descr OPEN THROMBECT AV FISTULA
Medium Descr THRMBC OPN ARVEN FSTL W/O REVJ DIAL GRF
Long Descr Thrombectomy, open, arteriovenous fistula without revision, autogenous or nonautogenous dialysis graft (separate procedure)
Status Code Active Code
Global Days 090 - Major Surgery
PC/TC Indicator (26, TC) 0 - Physician Service Code
Multiple Procedures (51) 2 - Standard payment adjustment rules for multiple procedures apply.
Bilateral Surgery (50) 0 - 150% payment adjustment for bilateral procedures does NOT apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 2 - Payment restriction for assistants at surgery does not apply to this procedure...
Co-Surgeons (62) 1 - Co-surgeons could be paid, though supporting documentation is required...
Team Surgery (66) 0 - Team surgeons not permitted for this procedure.
Diagnostic Imaging Family 99 - Concept Does Not Apply
APC Status Indicator Hospital Part B services paid through a comprehensive APC
ASC Payment Indicator Surgical procedure on ASC list in CY 2007; payment based on OPPS relative payment weight.
Type of Service (TOS) 2 - Surgery
Berenson-Eggers TOS (BETOS) P2F - Major procedure, cardiovascular-Other
MUE 1
CCS Clinical Classification 61 - Other OR procedures on vessels other than head and neck

This is a primary code that can be used with these additional add-on codes.

36907 CPT Add On MPFS Status: Active Code APC N ASC N1 Transluminal balloon angioplasty, central dialysis segment, performed through dialysis circuit, including all imaging and radiological supervision and interpretation required to perform the angioplasty (List separately in addition to code for primary procedure)
36908 CPT Add On MPFS Status: Active Code APC N ASC N1 Transcatheter placement of intravascular stent(s), central dialysis segment, performed through dialysis circuit, including all imaging and radiological supervision and interpretation required to perform the stenting, and all angioplasty in the central dialysis segment (List separately in addition to code for primary procedure)
LT Left side (used to identify procedures performed on the left side of the body)
GC This service has been performed in part by a resident under the direction of a teaching physician
22 Increased procedural services: when the work required to provide a service is substantially greater than typically required, it may be identified by adding modifier 22 to the usual procedure code. documentation must support the substantial additional work and the reason for the additional work (ie, increased intensity, time, technical difficulty of procedure, severity of patient's condition, physical and mental effort required). note: this modifier should not be appended to an e/m service.
51 Multiple procedures: when multiple procedures, other than e/m services, physical medicine and rehabilitation services or provision of supplies (eg, vaccines), are performed at the same session by the same individual, the primary procedure or service may be reported as listed. the additional procedure(s) or service(s) may be identified by appending modifier 51 to the additional procedure or service code(s). note: this modifier should not be appended to designated "add-on" codes (see appendix d).
52 Reduced services: under certain circumstances a service or procedure is partially reduced or eliminated at the discretion of the physician or other qualified health care professional. under these circumstances the service provided can be identified by its usual procedure number and the addition of modifier 52, signifying that the service is reduced. this provides a means of reporting reduced services without disturbing the identification of the basic service. note: for hospital outpatient reporting of a previously scheduled procedure/service that is partially reduced or cancelled as a result of extenuating circumstances or those that threaten the well-being of the patient prior to or after administration of anesthesia, see modifiers 73 and 74 (see modifiers approved for asc hospital outpatient use).
53 Discontinued procedure: under certain circumstances, the physician or other qualified health care professional may elect to terminate a surgical or diagnostic procedure. due to extenuating circumstances or those that threaten the well being of the patient, it may be necessary to indicate that a surgical or diagnostic procedure was started but discontinued. this circumstance may be reported by adding modifier 53 to the code reported by the individual for the discontinued procedure. note: this modifier is not used to report the elective cancellation of a procedure prior to the patient's anesthesia induction and/or surgical preparation in the operating suite. for outpatient hospital/ambulatory surgery center (asc) reporting of a previously scheduled procedure/service that is partially reduced or cancelled as a result of extenuating circumstances or those that threaten the well being of the patient prior to or after administration of anesthesia, see modifiers 73 and 74 (see modifiers approved for asc hospital outpatient use).
58 Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period: it may be necessary to indicate that the performance of a procedure or service during the postoperative period was: (a) planned or anticipated (staged); (b) more extensive than the original procedure; or (c) for therapy following a surgical procedure. this circumstance may be reported by adding modifier 58 to the staged or related procedure. note: for treatment of a problem that requires a return to the operating/procedure room (eg, unanticipated clinical condition), see modifier 78.
59 Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25.
62 Two surgeons: when 2 surgeons work together as primary surgeons performing distinct part(s) of a procedure, each surgeon should report his/her distinct operative work by adding modifier 62 to the procedure code and any associated add-on code(s) for that procedure as long as both surgeons continue to work together as primary surgeons. each surgeon should report the co-surgery once using the same procedure code. if additional procedure(s) (including add-on procedure(s) are performed during the same surgical session, separate code(s) may also be reported with modifier 62 added. note: if a co-surgeon acts as an assistant in the performance of additional procedure(s), other than those reported with the modifier 62, during the same surgical session, those services may be reported using separate procedure code(s) with modifier 80 or modifier 82 added, as appropriate.
74 Discontinued out-patient hospital/ambulatory surgery center (asc) procedure after administration of anesthesia: due to extenuating circumstances or those that threaten the well being of the patient, the physician may terminate a surgical or diagnostic procedure after the administration of anesthesia (local, regional block(s), general) or after the procedure was started (incision made, intubation started, scope inserted, etc). under these circumstances, the procedure started but terminated can be reported by its usual procedure number and the addition of modifier 74. note: the elective cancellation of a service prior to the administration of anesthesia and/or surgical preparation of the patient should not be reported. for physician reporting of a discontinued procedure, see modifier 53.
76 Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
78 Unplanned return to the operating/procedure room by the same physician or other qualified health care professional following initial procedure for a related procedure during the postoperative period: it may be necessary to indicate that another procedure was performed during the postoperative period of the initial procedure (unplanned procedure following initial procedure). when this procedure is related to the first, and requires the use of an operating/procedure room, it may be reported by adding modifier 78 to the related procedure. (for repeat procedures, see modifier 76.)
79 Unrelated procedure or service by the same physician or other qualified health care professional during the postoperative period: the individual may need to indicate that the performance of a procedure or service during the postoperative period was unrelated to the original procedure. this circumstance may be reported by using modifier 79. (for repeat procedures on the same day, see modifier 76.)
80 Assistant surgeon: surgical assistant services may be identified by adding modifier 80 to the usual procedure number(s).
82 Assistant surgeon (when qualified resident surgeon not available): the unavailability of a qualified resident surgeon is a prerequisite for use of modifier 82 appended to the usual procedure code number(s).
AQ Physician providing a service in an unlisted health professional shortage area (hpsa)
AS Physician assistant, nurse practitioner, or clinical nurse specialist services for assistant at surgery
CC Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed)
GV Attending physician not employed or paid under arrangement by the patient's hospice provider
GW Service not related to the hospice patient's terminal condition
Q6 Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area
RT Right side (used to identify procedures performed on the right side of the body)
SG Ambulatory surgical center (asc) facility service
X4 Episodic/focused services: for reporting services by clinicians who provide focused care on particular types of treatment limited to a defined period and circumstance; the patient has a problem, acute or chronic, that will be treated with surgery, radiation, or some other type of generally time-limited intervention; reporting clinician service examples include but are not limited to, the orthopedic surgeon performing a knee replacement and seeing the patient through the postoperative period
X5 Diagnostic services requested by another clinician: for reporting services by a clinician who furnishes care to the patient only as requested by another clinician or subsequent and related services requested by another clinician; this modifier is reported for patient relationships that may not be adequately captured by the above alternative categories; reporting clinician service examples include but are not limited to, the radiologist's interpretation of an imaging study requested by another clinician
XE Separate encounter, a service that is distinct because it occurred during a separate encounter
XP Separate practitioner, a service that is distinct because it was performed by a different practitioner
XS Separate structure, a service that is distinct because it was performed on a separate organ/structure
XU Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service
Date
Action
Notes
2001-01-01 Changed Code description changed.
1999-01-01 Added First appearance in code book in 1999.
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