Billing code 37185: Arterial thrombectomyMedicare rate & RVUs in Washington
Report for mechanical thrombectomy of an additional arterial vessel in the same vascular family during a primary thrombectomy session.
Medicare pays $473.22–$536.11 for 37185 in the office in Washington, from Rest Of Washington to Seattle (King Cnty). Which amount applies depends on the service address.
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
On this page 9 sections
What 37185 covers
This add-on represents catheter-based mechanical removal of thrombus from an additional artery in the same vascular family as the vessel treated primarily. Interventional radiologists and vascular surgeons commonly perform the work in an angiography suite or operating room. The thrombectomy may involve intraprocedural thrombolytic medication and fluoroscopic guidance as part of the service. The additional vessel must be distinct from the initial vessel treated under the primary thrombectomy service.
Report 37185 with the primary arterial thrombectomy code for the initial vessel, not as a stand-alone service. The operative or procedure report should identify the additional vessel and document mechanical thrombectomy there, along with the relationship to the primary treatment. CMS treats this as an add-on paid within the primary procedure's global period. The code is already priced as bilateral, so modifier 50 does not increase payment.
This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.
Where 37185 pays more and less in Washington
| Payment locality | Office | Facility |
|---|---|---|
| Rest Of Washington | $473.22 | $138.74 |
| Seattle (King Cnty) | $536.11 | $146.36 |
How the 37185 rate is calculated
Each of 37185’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.
How the rate is built · 37185
RVUs × geographic indexes × conversion factor
Swap in your local Medicare rate.
Work 3.20Practice expense 9.95Malpractice 0.59
All indexes start at 1.000 (the national rate). Enter a ZIP or drag a slider.
Payment rules and modifiers for 37185
The CMS indicators that decide how 37185 is paid alongside other services.
CMS payment indicators · 37185
Arterial thrombectomy
| Rule | CMS value | What it means |
|---|---|---|
| Global period | ZZZ | Add-on code: falls within the primary procedure’s global period. |
| Multiple procedures | 0 | No multiple-procedure reduction. |
| Bilateral (modifier 50) | 2 | Already bilateral by definition: paid once at 100%. |
| Assistant at surgery (80/81/82/AS) | 1 | Not paid (statutory restriction). |
| Co-surgeons (62) | 2 | Permitted. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 0 | Physician service: no professional/technical split. |
37185 compared with similar codes
Compare codes
37185 vs 37184 vs 37186 vs 37187: national Medicare rates
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How to choose
- 37184Arterial thrombectomy
- 37184 covers the initial vessel treated with primary arterial mechanical thrombectomy. Use 37185 for an additional vessel in the same vascular family.
- 37186Arterial thrombectomy
- 37186 describes a secondary arterial thrombectomy service. Code 37185 is for primary mechanical thrombectomy in an additional vessel within the same vascular family.
- 37187Venous thrombectomy
- 37187 is for mechanical thrombectomy in the venous system; 37185 concerns an additional arterial vessel.
37185 billing questions
When should 37185 be reported instead of 37184?
Use 37184 for the initial arterial vessel treated with primary mechanical thrombectomy. Report 37185 for each qualifying additional vessel in the same vascular family.
Can 37185 be billed by itself?
No. It is an add-on and must be reported with the primary procedure for the initial vessel.
What documentation supports reporting an additional vessel?
The procedure report should identify the additional artery and document mechanical thrombectomy performed there, distinct from the initial vessel.
Should modifier 50 be appended for bilateral treatment?
The code is already priced as bilateral. Modifier 50 does not increase payment.
How does 37185 differ from 37186?
37185 identifies primary mechanical thrombectomy in an additional vessel within the same vascular family. Code 37186 describes a secondary arterial thrombectomy service rather than this additional-vessel primary service.
Where these rates come from
FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.
CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027
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