Billing code 33258: Atrial ablationMedicare rate & RVUs in Missouri
Add-on extensive atrial ablation performed during another open cardiac operation to treat atrial fibrillation, without cardiopulmonary bypass.
CMS doesn’t publish an office rate for 33258 in Missouri.
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 33258 covers
Code 33258 represents an extensive set of surgical lesions in atrial tissue to interrupt pathways sustaining atrial fibrillation. A cardiac surgeon may perform it during another open cardiac operation, such as valve surgery or coronary artery bypass, using the operative exposure. It describes an adjunct to that operation, not a standalone ablation session, and distinguishes an extensive lesion set from a limited one.
Report it only with an eligible primary open cardiac procedure; CMS treats the add-on service within that procedure’s global period. The operative report should support the atrial fibrillation treatment, extent of the lesion set, concurrent cardiac operation, and absence of cardiopulmonary bypass. Use the extensive add-on code for this situation; a limited lesion set or use of bypass points to a different code in the family.
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 33258 pays more and less in Missouri
The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.
| Payment locality | Office | Facility |
|---|---|---|
| Metropolitan Kansas City | Unavailable | $622.60 |
| Metropolitan St. Louis | Unavailable | $627.24 |
| Rest Of Missouri | Unavailable | $607.55 |
How the 33258 rate is calculated
Each of 33258’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 · 33258
RVUs × geographic indexes × conversion factor
Work10.73
10.73 RVUs× 1.000 GPCI
Practice expense5.75
5.75 RVUs× 1.000 GPCI
Malpractice2.57
2.57 RVUs× 1.000 GPCI
Adjusted RVUs
19.0500
Conversion factor
$33.4009
Medicare rate
$636.29
Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.
Payment rules and modifiers for 33258
The CMS indicators that decide how 33258 is paid alongside other services.
CMS payment indicators · 33258
Atrial ablation
| 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) | 0 | The 150% bilateral adjustment doesn’t apply. |
| Assistant at surgery (80/81/82/AS) | 2 | Paid. |
| Co-surgeons (62) | 0 | Not permitted. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 0 | Physician service: no professional/technical split. |
What modifiers do to the payment
Modifier 80 · payment effect
With and without the modifier
33258 without 80 · national facility
$636.29
Atrial ablation
33258-80 · Assistant: 16%
$101.81
A physician assistant at surgery is paid 16% of the surgeon’s fee schedule amount.
33258 compared with similar codes
Compare codes · National
5 codes, side by side
How to choose
- 33257Atrial ablation
- Choose 33257 for limited atrial ablation performed with another open cardiac procedure. Code 33258 is for the more extensive lesion set.
- 33259Atrial ablation
- Both describe extensive atrial ablation as an add-on during another open cardiac procedure. Use 33259 when cardiopulmonary bypass is used; 33258 is for cases without bypass.
- 33255Atrial ablation
- 33255 describes extensive surgical atrial ablation without bypass when it is not reported as the add-on during another open cardiac procedure.
- 33266Atrial ablation
- 33266 is the extensive endoscopic approach. Code 33258 describes the open surgical approach without cardiopulmonary bypass.
33258 billing questions
Can 33258 be reported by itself?
No. It is an add-on for extensive atrial ablation performed with another eligible open cardiac procedure, and CMS places it within that primary procedure’s global period.
How does 33258 differ from 33257?
33258 describes an extensive lesion set; 33257 is for limited atrial ablation performed during another open cardiac procedure.
When should 33259 be used instead?
Use 33259 for the extensive add-on when cardiopulmonary bypass is used. Code 33258 is the extensive add-on without bypass.
What documentation supports reporting 33258?
The operative report should establish atrial fibrillation treatment, an extensive atrial lesion set, the concurrent open cardiac operation, and whether cardiopulmonary bypass was used.
Can it accompany valve surgery or bypass surgery?
It may be reported as an add-on when extensive atrial ablation is performed during an eligible open cardiac operation, such as valve surgery or coronary artery bypass.
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
Show the CMS file lines behind this rate
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