CPT code 37221 – Iliac artery stent placement

Key takeaways

CPT code 37221 was deleted effective January 1, 2026, along with the entire 37220-37235 lower extremity revascularization family.

Iliac artery stent placement is now reported with 37258 for a straightforward lesion or 37260 for a complex lesion.

CPT defines straightforward as a stenosis and complex as a 100% occlusion, so the operative note must state which was treated.

The new codes bundle vascular access, selective catheterization, lesion crossing, angioplasty in the same artery, and all imaging supervision and interpretation.

Claims submitted with 37221 for a 2026 date of service are rejected, so rebill legacy cases under the correct territory code.

Pabau’s claims management software applies payer-specific rules and submits vascular claims through the Claim.MD clearinghouse.

CPT code 37221 was deleted on January 1, 2026

CPT code 37221 is no longer a valid code. The American Medical Association (AMA) deleted it effective January 1, 2026, together with the whole lower extremity revascularization family from 37220 through 37235. Claims submitted with 37221 for a 2026 date of service are rejected.

Through 2025, 37221 carried this descriptor:

Revascularization, endovascular, open or percutaneous, iliac artery, unilateral, initial vessel; with transluminal stent placement(s), includes angioplasty within the same vessel, when performed.

That wording is now historical. It still matters when you work a 2025 claim, and nowhere else.

In its place, CPT 2026 introduced 46 codes running from 37254 to 37299. They are organized by vascular territory rather than by vessel name, and within each territory they split by lesion complexity. The four territories are iliac, femoral/popliteal, tibial/peroneal, and a newly recognized inframalleolar territory.

Each deleted code maps to two successors, not one. The table below is the crosswalk for the iliac family that 37221 belonged to, as published in the SCAI 2026 lower extremity revascularization code guide.

The 2026 replacement codes for iliac artery stent placement

Iliac artery stent placement, unilateral, initial vessel, is now reported with either 37258 or 37260. The choice rests entirely on how the operative note characterizes the lesion.

The official descriptor for 37258 runs to four clauses:

• Revascularization, endovascular, open or percutaneous, iliac vascular territory, with transluminal stent placement, including transluminal angioplasty when performed,
• including all maneuvers necessary for accessing and selectively catheterizing the artery and crossing the lesion,
• including all imaging guidance and radiological supervision and interpretation necessary to perform the stent placement and angioplasty when performed, within the same artery, unilateral;
• straightforward lesion, initial vessel.

37260 carries identical wording, ending instead with complex lesion, initial vessel. The two codes differ by one clause, and that clause moves the payment by thousands of dollars.

Three reporting rules govern the iliac territory. Only 37254, 37256, 37258, and 37260 describe the initial artery treated. No more than two add-on codes may be reported for additional vessels in the same extremity. When several lesions are treated, report the single code for the most complex service. Never use an add-on code for another lesion in a vessel you have already coded.

Straightforward or complex: the one line that picks the code

CPT 2026 defines the two lesion categories narrowly. A straightforward lesion is a stenosis, meaning some blood still flows through the segment. A complex lesion is a 100% occlusion, with no flow at all. There is no middle category, and a severe stenosis is still straightforward.

This is the change that catches vascular coding teams out. Under 37221 the stent itself decided the code, so operative note templates were built to capture stent make, model, and size. None of those fields answer the question CPT now asks. Say the note reads high-grade stenosis of the left common iliac, with no word on whether flow was preserved. The coder cannot pick between 37258 and 37260, and has to query the physician.

What the new iliac codes bundle

The 2026 descriptors absorb far more work than the codes they replaced. Reading the descriptor closely is the fastest way to avoid an unbundling denial. The list of included services now sits inside the code text itself.

The bundled imaging is the change most likely to surprise a billing team. Practices that routinely added diagnostic angiography supervision and interpretation lines to an iliac stent claim will see those lines reject. Diagnostic angiography that precedes the decision to intervene is a separate question. Payer policy on it varies, so confirm the rules with your MAC before you strip codes out of your charge templates.

Clinical context: What the iliac revascularization procedure involves

Coders working from operative reports need to recognize the procedural steps behind an iliac stent claim. The typical workflow follows this sequence:

1. Vascular access: A sheath is placed percutaneously, usually at the common femoral artery, under fluoroscopic or ultrasound guidance.
2. Diagnostic angiography: Contrast is injected to visualize the iliac stenosis or occlusion. The imaging performed to guide and document the intervention is bundled into 37258 or 37260.
3. Lesion crossing: A wire is passed through the lesion. An occlusion may need a re-entry device, and that work is included in the code.
4. Balloon angioplasty: A balloon catheter dilates the stenotic segment. Performed in the same artery as the stent, it is bundled.
5. Stent deployment: A self-expanding or balloon-expandable stent is deployed across the lesion.
6. Completion angiography: Post-procedure imaging confirms patency and stent position, and it is also bundled.

The underlying diagnosis is almost always peripheral arterial disease (PAD), most often atherosclerotic iliac occlusive disease causing claudication or chronic limb-threatening ischemia. Correct ICD-10 pairing supports medical necessity and is a leading denial driver.

Modifiers for iliac stent claims in 2026

Both 37258 and 37260 are unilateral codes, so laterality has to reach the claim somehow. Getting that wrong is a frequent source of denial management work on iliac stent claims.

Billing kissing iliac stents under the 2026 codes

The kissing iliac stent technique places stents in both common iliac arteries at once, usually at the aortic bifurcation. Because the codes are unilateral, this is two lines, not one code with a units multiplier. Work through it in this order:

1. Confirm the operative note documents stent deployment on each side and identifies the vessels separately.
2. Read the lesion character for each side. One iliac may be a stenosis while the other is occluded.
3. Assign 37258 or 37260 per side on its own merits, since the two sides can carry different codes.
4. Apply the laterality format your payer wants, either modifier -50 on one line or RT and LT on two lines.
5. Attach documentation confirming bilateral deployment to the claim.

Payer policy on modifier -50 against RT and LT still varies, so confirm the format with the payer or MAC before billing. A mismatch here is a frequent cause of medical billing denial codes on otherwise clean vascular claims.

Medicare reimbursement for 37258 and 37260

The split by lesion complexity moved money as well as code numbers. Under the CY2026 Medicare Physician Fee Schedule, the straightforward iliac stent code pays less than 37221 did, while the complex code pays considerably more. The figures below come from Medtronic’s 2026 lower extremity revascularization coding and payment guide, which reproduces the CY2026 national rates.

Read those two percentages together. A practice that mostly stents stenoses takes a cut in 2026, while one that mostly reopens occlusions gains. Roughly $4,900 separates the two non-facility rates. A vague operative note therefore carries a price in dollars as well as in coder time.

National figures are a planning tool, not a payment forecast. Your locality, your billing setting, and your geographic practice cost index all move the number. Look up the amount that applies to you before you build it into a budget:

• CMS Physician Fee Schedule Look-Up Tool for facility and non-facility rates by geographic locality
• FastRVU RVU lookup for work, practice expense, and malpractice RVU values with geographic adjustment factors

Medicare coverage requirements and prior authorization (CMS article A57590)

CMS Local Coverage Article A57590 governs Medicare coverage for non-coronary vascular stents, iliac artery interventions included. Revision 5 of that article took effect January 1, 2026. It removed the deleted 37220-37235 codes and added the 37254-37299 range, so the coverage criteria now attach to 37258 and 37260.

Covered indications typically include symptomatic peripheral arterial disease with documented hemodynamic significance, failure of conservative management, and imaging confirmation of the lesion. Key documentation requirements include:

• Ankle-brachial index (ABI) or segmental pressure measurements confirming hemodynamic impairment
• Arterial imaging report (CTA, MRA, or diagnostic angiography) identifying the iliac lesion
• Documentation of symptom duration and conservative treatment history, such as exercise therapy and pharmacotherapy
• Clinical indication supporting medical necessity, tied to the assigned ICD-10 diagnosis code

Prior authorization requirements depend on the payer and the care setting. Medicare Fee-for-Service traditionally does not require it for most outpatient vascular procedures, but Medicare Advantage plans often do. Commercial payers set their own thresholds. Check requirements through insurance eligibility verification before the procedure is scheduled. Your MAC may also publish Local Coverage Determinations that add criteria beyond A57590.

Documentation requirements to support an iliac stent claim

A complete record for 37258 or 37260 has to carry several specific elements. A missing element is the root cause of most medical necessity denials on these claims. Treat superbill documentation as the claim’s first line of defense.

• Lesion character: Stenosis or 100% occlusion, stated explicitly. This is the element that picks the code, and it is the one legacy templates omit
• Vascular territory: Iliac, femoral/popliteal, tibial/peroneal, or inframalleolar, named for each lesion treated
• Vessel identity and laterality: Which iliac artery, meaning common, external, or internal, and which side
• Stent detail: Manufacturer, model, size, and deployment site within the iliac vessel
• Access method: Percutaneous puncture site or open cut-down, matching the open or percutaneous descriptor
• Pre- and post-procedure imaging: Images showing lesion location, pre-intervention stenosis grade, and post-stent patency
• Hemodynamic measurements: ABI or pressure gradients before and after the intervention
• Clinical indication: Diagnosis linked to a valid ICD-10-CM code confirming medical necessity
• Consent documentation: Signed procedure consent for elective cases

Practices that run a medical billing compliance checklist before submission catch these omissions early. The claim can still be fixed at that point, before a denial lands.

What to do with legacy 37221 claims

The code you report follows the date of service, not the date you send the claim. A procedure performed on or before December 31, 2025 stays on 37221 forever. You will keep using the deleted code on corrected claims, appeals, and late submissions for those cases, and that is correct.

Only a 2026 date of service moves to 37258 or 37260. Three practical consequences follow:

• Keep 37221 in your charge master as an inactive historical entry rather than deleting it, so old claims can still be worked
• Put a hard stop on 37220-37235 for any 2026 encounter date, which is a rule your billing system can enforce at charge entry
• Re-read any 2026 claim that was auto-populated from a 2025 template, since those are the ones that carry a deleted code

AAPC’s Codify entry for 37221 now carries the deleted-code flag. That is a quick status check when a payer questions an old line.

Common denial reasons for iliac stent claims

Knowing why these claims get denied is the fastest path to a cleaner clean claim rate. The table below covers the triggers seen most often since the 2026 codes took effect.

Pabau’s 837P claim file submission workflow through Claim.MD flags coding mismatches before claims reach the payer, which cuts preventable denials on peripheral vascular claims.

ICD-10 diagnosis codes commonly paired with iliac stent placement

Diagnosis pairing is the second half of a payable iliac stent claim and it receives far less attention than the procedure code. The diagnosis must reflect the documented clinical condition and satisfy the payer’s coverage criteria. Verify each code against the current ICD-10-CM tabular list for the applicable fiscal year.

Two pairings go wrong often enough to be worth naming. Claudication in a patient with established atherosclerosis belongs on I70.21-, not on a symptom code such as R26.89, because the etiology is documented. And I70.92 never stands alone, since the tabular list instructs you to code the underlying atherosclerosis first.

Cross-reference your chosen diagnosis against the payer’s coverage list before the claim goes out. Pabau’s electronic remittance advice workflow flags CARC denial reason codes tied to ICD-10 mismatches, which gives billing teams a clear route to appeal or correction.

Keeping vascular billing current when the code set changes

A code-set change on this scale exposes how much of a practice’s billing logic lives in habit. Charge templates still list the deleted codes. Superbills still name 37221. The coder still reaches for the stent detail rather than the lesion character, because that is what mattered for a decade.

Practice management software like Pabau keeps that logic in one place instead of in muscle memory. Charge codes, payer-specific modifier rules, and documentation prompts sit in the system. A change to the code set becomes an update your team applies once. Claims go out through the Claim.MD clearinghouse, which submits electronic CMS-1500 claims to thousands of US insurance payers and returns electronic remittance advice for reconciliation.

The outcome your billing team feels is a shorter loop between the procedure and the payment. Coding errors surface before submission instead of in a denial letter six weeks later. The people working those accounts spend their time on payer disputes that matter.

Keep vascular billing current when the codes change

Pabau’s claims management software holds your charge codes, payer-specific modifier rules, and documentation prompts in one place. A CPT update then becomes a settings change your team applies once.

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Conclusion

CPT 37221 is gone, and no amount of payer-by-payer checking will bring it back. For any 2026 date of service, iliac artery stent placement is 37258 when the lesion is a stenosis. It is 37260 when the lesion is a total occlusion. The rest of the claim follows from that one determination, including the roughly $4,900 difference in national non-facility payment.

So the work in front of a vascular billing team is narrow and finite. Purge the deleted range from your charge templates and add a lesion character field to the operative note. Then strip the imaging supervision lines that the new codes now absorb. Pabau’s claims management software supports that with clearinghouse submission, eligibility verification, and remittance reconciliation. Book a demo to see how it handles a specialty billing workflow end to end.

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