ModifiedBlue Cross Blue Shield - KansasPolicy N/A

Extracranial Carotid Artery Stenting

Policy governing medical necessity and coverage stance for carotid angioplasty with stenting, embolic protection, and transcarotid artery revascularization for members of Blue Cross and Blue Shield of Kansas.

Policy Summary

PayerBlue Cross Blue Shield - Kansas

PolicyExtracranial Carotid Artery Stenting

Policy CodePolicy N/A

Change TypeMaterial: TCAR designated investigationalcoding revisions

Effective DateJuly 27, 2024

Next Review DateN/A

Key ActionVerify member benefits and obtain prior authorization with documentation of symptomatic status, percent stenosis, and operator credentialing.

SourceLink

POLICY UPDATE CHANGES

Transcarotid artery revascularization is considered experimental / investigational for all indications.

Removed CPT code 37218 from coding section.

Updated coding section to list CPT codes 37215, 37216, 37217 and clarify coding is informational and contingent on policy criteria.

50%-99%NASCET stenosis threshold

120 daysSymptom window (max)

2007Original effective year

2026-01-27Latest review

Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.

Primary stent codes listed

Grade DUSPSTF screening stance

Coverage Criteria and Evidence Summary

Medically necessary indications for carotid angioplasty with stenting and embolic protection

Covered when ALL of the following are met:

Coverage criteria for CAS: 1. 50% to 99% stenosis measured by NASCET criteria; AND 2. Symptoms of focal cerebral ischemia (transient ischemic attack, monocular blindness) in the previous 120 days with symptom duration <24 hours, or nondisabling stroke; AND 3. Anatomic contraindication to carotid endarterectomy (examples: prior neck radiotherapy or surgery, surgically inaccessible lesion, spinal immobility, tracheostomy).NASCET 50%–99%; symptoms within 120 days; symptom duration <24 hours

Embolic protection used with stenting is implied by policy.

Experimental / investigational - other indications

Not covered - experimental/investigational: Carotid angioplasty with associated stenting and embolic protection is considered experimental/investigational for all other indications, including individuals who are suitable candidates for carotid endarterectomy and individuals with carotid artery dissection.

Applies when the covered criteria are not met.

Not covered - angioplasty without stent and TCAR

Carotid angioplasty without stenting: Carotid angioplasty without associated stenting and embolic protection is considered experimental/investigational for all indications.

Intent clarified in Policy Guidelines (stenting intended; angioplasty-alone investigational).

Transcarotid artery revascularization (TCAR): Transcarotid artery revascularization is considered experimental/investigational for all indications.

Policy explicitly lists TCAR as investigational despite background description.

Evidence-based coverage considerations

Evidence-informed considerations for when CAS or CEA may provide net clinical benefit

Landmark-trial benchmarks for net benefit: Periprocedural death or stroke rates must be below trial-defined thresholds to obtain net clinical benefit: historically asymptomatic <3% and symptomatic <6%; contemporary consensus has suggested lower benchmarks (eg, asymptomatic ~2%, symptomatic ~4%).asymptomatic <3% (historical); symptomatic <6% (historical); suggested contemporary: asymptomatic ~2%, symptomatic ~4%

Benchmarks derived from landmark trials and consensus documents.

Patient selection factors favoring CAS: CAS may be considered when patients have increased surgical or anesthetic risk or anatomic factors that make CEA high risk (eg, prior neck surgery or radiotherapy, surgically inaccessible lesions, contralateral occlusion, severe cardiac or pulmonary dysfunction).

Supported by trial rationale and exclusions in landmark and contemporary trials.

Operator and center experience: Operator credentialing and experience should be considered because trials with highly selected interventionalists (eg, CREST) reported lower periprocedural risks for CAS; less stringent operator selection in other trials was associated with higher complication rates.

Comparative effectiveness

Coverage considerations informed by evidence

CAS vs CEA evidence summary: Randomized trials and meta-analyses demonstrate that CAS often has higher periprocedural stroke/death rates than CEA in symptomatic and mixed populations; long-term ipsilateral stroke rates after the perioperative period are similar between CAS and CEA; restenosis may be more frequent after CAS in some trials.

Summary based on RCTs (eg, CREST, ICSS) and systematic reviews.

TCAR

TCAR evidence

TCAR comparative evidence: Evidence for TCAR is primarily from nonrandomized studies, registries, and meta-analyses; pooled 30-day stroke or death rate reported ~1.89% and observational comparisons show lower perioperative stroke/death versus transfemoral CAS but no consistent superiority versus CEA for composite outcomes; certainty is limited by study design and potential biases.

Certainty limited; systematic reviews and VQI registry analyses inform this summary.

CREST-2

Medical management vs revascularization for asymptomatic high-grade stenosis

CREST-2 findings: CREST-2 enrolled patients with high-grade (≥70%) asymptomatic carotid stenosis in two parallel trials (CAS vs medical management; CEA vs medical management). CAS plus intensive medical management reduced the primary composite outcome compared with medical management alone in the CAS trial, while CEA plus medical management did not show a significant difference compared with medical management alone; direct head-to-head CAS versus CEA comparisons were not provided by CREST-2.

CREST-2 results should be interpreted in context of trial design comparing each procedure to medical therapy rather than each other.

General evidence stance

Evidence summary and stance

Evidence base: The evidence on TCAR is limited to nonrandomized and observational studies; systematic reviews found no significant difference between TCAR and CEA for composite stroke/death/MI but did find reductions in MI and cranial nerve injury with TCAR in some analyses.

Limitations of evidence may affect coverage decisions where randomized evidence is preferred.

Guideline-based clinical criteria

Guideline-informed considerations

When TCAR or CAS may be considered: 1) TCAR or CAS may be considered when the patient is high anatomic or physiologic surgical risk making CEA less desirable; OR 2) when arterial anatomy is unfavorable for transfemoral CAS or for open surgery. Society guidance generally prefers CEA over TF-CAS in low- and standard-risk symptomatic patients and recommends case-by-case selection for TCAR, favoring TCAR in high-risk patients.

Reflects SVS and ASA guideline recommendations: preferential CEA in many symptomatic standard-risk patients; TCAR preferable to TF-CAS or CEA in high-risk patients per SVS.

Coverage Criteria / Guideline-based indications

Covered when guideline-based clinical criteria are met:

Symptomatic CAS eligibility: CAS is an alternative to CEA for symptomatic patients when lumen narrowing is >70% by validated noninvasive imaging OR >50% by catheter angiography AND the anticipated periprocedural stroke or mortality rate is <6%.stenosis >70% noninvasive OR >50% by angiography; perioperative risk <6%

Based on American Stroke Association recommendations (COR I/LOE B where noted).

Timing consideration: When revascularization is indicated for TIA or stroke and there are no contraindications, performing the intervention within 2 weeks of the index event is reasonable.within 2 weeks

ASA recommendation (COR IIa).

Asymptomatic selection: Selection of asymptomatic patients should be individualized by comorbidities, life expectancy, and preferences; prophylactic CAS may be considered in highly selected asymptomatic patients (minimum 60% by angiography or 70% by validated duplex) but effectiveness versus medical therapy is not well established.

Coverage determinations must follow the member's contract benefits and any applicable state or federal mandates, which take precedence when determining whether a service is covered for an individual member. Providers should verify the member's benefits and eligibility at the time of service to determine coverage or noncoverage.

Patients with limited expected survival were commonly excluded from landmark trials because the net clinical benefit of revascularization depends on surviving long enough for long-term stroke reduction to outweigh immediate periprocedural harms. Trial-based guidance therefore considers anticipated life expectancy when selecting patients for carotid revascularization; interventions are generally inappropriate when life expectancy is shorter than the trial-specified horizons (commonly on the order of <2–5 years depending on symptom status and stenosis degree).

There are no randomized controlled trials supporting carotid artery stenting (CAS) for treatment of carotid dissection. Guidelines rate CAS for carotid dissection as a Class IIb, Level C recommendation and typically reserve intervention for patients who fail conservative therapy; CAS for dissection is therefore not supported as a routine indication.

Current society guidance does not recommend routine use of transcarotid artery revascularization (TCAR) in low surgical–risk symptomatic patients. For many symptomatic patients with severe stenosis, carotid endarterectomy (CEA) remains the preferred approach unless specific anatomic or physiologic factors favor CAS/TCAR.

Carotid revascularization (CEA or CAS) is not recommended when stenosis is <50%, for chronic total occlusion of the targeted carotid artery, or for patients with severe disability from cerebral infarction that precludes preservation of useful function. These scenarios were excluded or discouraged in guideline statements and in the policy's coverage logic.

For informational purposes, the U.S. Preventive Services Task Force recommends against routine screening for asymptomatic carotid artery stenosis (USPSTF Grade D). This recommendation informs a preference against screening or prophylactic revascularization in the general asymptomatic population.

Carotid angioplasty with stenting and embolic protection performed for indications other than the policy's specified covered criteria is considered experimental/investigational. The policy explicitly states CAS with embolic protection is investigational for all other indications when the coverage criteria are not met.

In trials where superiority of carotid endarterectomy (CEA) or carotid artery stenting (CAS) over best medical therapy was not demonstrated, adding revascularization to contemporary medical therapy may provide uncertain benefit. Such trial results support careful consideration of medical management when superiority has not been established.

Use of TCAR as a routine substitute for CEA in low- or standard-risk symptomatic patients is not supported by randomized controlled trial evidence. The evidence base for TCAR consists primarily of nonrandomized and observational studies, and guideline documents note that data are inadequate to recommend TCAR routinely in low surgical–risk symptomatic patients.

CAS is considered experimental/investigational when the policy's coverage criteria are not met. Examples noted in the policy include complete (100%) occlusion, symptomatic stenosis that does not meet the stated thresholds, symptomatic stenosis <50%, and other noncovered scenarios; procedures for indications outside the covered criteria risk denial as investigational.

Within the portion of the document referenced here there are no explicit standalone statements labeled 'not medically necessary' beyond the investigational/experimental designations already described; the policy text instead frames noncovered situations as experimental/investigational and directs review of member contract benefits and applicable mandates.

Coding and Measurement Thresholds

Regulatory device approvals (informational)mixed

PMA device listings and 510(k) numbers

Multiple FDA PMA and 510(k) approvals for carotid stents and embolic protection devices (product codes NIM and NTE) are listed in Tables 1 and 2 (see document).

Covered CPT Codes (informational; coverage contingent on policy criteria)CPT

37215	Transcatheter placement of intravascular stent(s), cervical carotid artery, open or percutaneous, including angioplasty, when performed, and radiological supervision and interpretation; with distal embolic protection.
37216	Transcatheter placement of intravascular stent(s), cervical carotid artery, open or percutaneous, including angioplasty when performed, and radiological supervision and interpretation; without distal embolic protection.
37217	Transcatheter placement of intravascular stent(s), intrathoracic common carotid artery or innominate artery by retrograde treatment, open ipsilateral cervical carotid artery exposure, including angioplasty, when performed, and radiological supervision and interpretation.

NASCET stenosis — 50% to 99% (NASCET measurement)

NASCET stenosis range50% to 99% (NASCET measurement)

Measurement methodNorth American Symptomatic Carotid Endarterectomy Trial (NASCET) measurement specified

Coverage contextRequired element of medical necessity for carotid angioplasty with stenting and embolic protection

Symptom window — Symptoms in prior 120 days; symptom duration <24 hours

Symptom timing windowSymptoms of focal cerebral ischemia in the previous 120 days

Symptom duration limitSymptom duration less than 24 hours (or nondisabling stroke) specified for eligibility

Provider Actions, Prior Authorization and Documentation

Prior Authorization

Verify benefits / Prior Authorization

Verify member benefits and prior authorization requirements at the time of service. Member contract language and state/federal mandates take precedence; contact Blue Cross and Blue Shield of Kansas Customer Service to confirm coverage.

Benefit verification required at time of service
Member contract precedence

Prior Authorization

Prior authorization for TCAR/CAS/CEA

Prior authorization is required when requesting carotid stenting (CPT codes 37215, 37216, 37217 as listed) or other CAS/TCAR/CEA procedures that are subject to this policy. Requests should include the planned procedure and documentation that the procedure will be performed in accordance with the Policy section to be considered medically necessary.

Prior authorization required for carotid stent placement codes listed (37215, 37216, 37217) when applicable
Coverage only if procedure is performed per Policy criteria

Background and Rationale

Carotid angioplasty with stenting (CAS) and transcarotid artery revascularization (TCAR) are less‑invasive alternatives to carotid endarterectomy (CEA) intended to prevent future stroke in patients with carotid stenosis. CAS typically employs embolic protection devices deployed proximally (flow reversal) or distally (filters), while TCAR is a hybrid approach using direct cervical carotid access with flow‑reversal embolic protection; the policy notes that TCAR evidence is limited to observational studies and that TCAR is considered investigational for all indications in this policy.

Definitions and Abbreviations

Embolic protection device (EPD) — device deployed proximally or distally to reduce thromboembolic stroke risk

EPD purposeDevice deployed to reduce risk of thromboembolic stroke during carotid artery stenting

Deployment approachesCan be deployed proximally (with flow reversal) or distally (using a filter)

Typical useEmbolic protection devices are almost uniformly used during CAS; carotid angioplasty without stent is rarely performed

Transcarotid artery revascularization (TCAR) — stenting technique with direct cervical carotid exposure and flow-reversal for high-risk CEA patients

TCAR definitionStenting technique using direct cervical carotid artery exposure with flow-reversal embolic protection

Patient selection

Policy Summary

PayerBlue Cross Blue Shield - Kansas

PolicyExtracranial Carotid Artery Stenting

Policy CodePolicy N/A

Change TypeMaterial: TCAR designated investigationalcoding revisions

Effective DateJuly 27, 2024

Next Review DateN/A

Key ActionVerify member benefits and obtain prior authorization with documentation of symptomatic status, percent stenosis, and operator credentialing.

SourceLink

On This Page

Operator experience important to replicate trial outcomes.

Consideration of contemporary medical therapy: Decisions about revascularization should account for intensive modern medical management as a comparator; recent randomized trials (CREST-2) compared intensive medical therapy alone to medical therapy plus CAS or CEA and influence patient selection for revascularization.

CREST-2 and other contemporary trials inform choice between revascularization and medical therapy.

asymptomatic >=60% angiography or >=70% duplex (select cases)

ASA: COR IIb; evidence limited.

Symptom types includedTransient ischemic attack (TIA) or monocular blindness or nondisabling stroke

acceptable periprocedural death or stroke rate — asymptomatic <3%; symptomatic <6%

Acceptable periprocedural death/stroke benchmarksAsymptomatic: <3%; Symptomatic: <6%

RationaleBenchmarks derive from landmark trials as thresholds for achieving net clinical benefit

Implication for authorizationLocal/performance rates exceeding these thresholds may negate net benefit and affect coverage decisions

Stenosis thresholds — Symptomatic >70% by noninvasive or >50% by angiography; revascularization not recommended when <50% or chronic total occlusion

Symptomatic stenosis thresholds>70% by noninvasive imaging OR >50% by catheter (angiographic) measurement for symptomatic patients

When revascularization not recommendedRevascularization not recommended when stenosis <50% or for chronic total occlusion

Guideline nuance for asymptomatic casesProphylactic intervention in asymptomatic patients is reserved for highly selected cases per guideline thresholds (eg, minimum 60% angiography / 70% duplex) and is not routinely recommended

Documentation Required

Clinical justification and risk status for TCAR

When requesting coverage for TCAR, include clinical justification that specifies whether the patient is standard- or high-risk for CEA, the indication for revascularization (symptomatic vs asymptomatic), timing of symptoms, anatomic contraindications to CEA if applicable, and any registry or trial participation.

Document patient risk status (standard vs high surgical risk) and specific anatomic/physiologic reasons if claiming high risk
State symptomatic status and timing of index event (eg, within 120 days for symptomatic patients)
Provide evidence of why CEA is contraindicated when CAS/TCAR proposed

Prior Authorization

Authorization for carotid stenting

For authorization of carotid stenting (CAS), submit comparative evidence of expected perioperative risk and symptom status and demonstrate that the case meets policy indications (eg, symptomatic 50–99% NASCET with anatomic contraindication to CEA). Procedures proposed for indications outside policy criteria are subject to denial.

Provide expected perioperative risk and symptomatic documentation
CAS coverage limited to indications meeting Policy; other indications considered investigational
Denial risk for procedures outside covered criteria

Step Therapy

Step therapy note

This section does not enumerate a separate step-therapy requirement. CAS is presented in this policy as an alternative to medical therapy and CEA in specified situations; confirm the member contract for any utilization management rules.

No step-therapy specified in policy
CAS considered an alternative to medical therapy and CEA in defined indications

Note

Consideration of intensive medical management first

Consideration should be given to intensive contemporary medical management (eg, as informed by CREST-2) before proceeding with revascularization in asymptomatic high-grade stenosis; documentation should show that medical management was considered and discussed with the patient when applicable.

CREST-2 implications: intensive medical management may be appropriate first-line for asymptomatic high-grade stenosis
Document discussion of medical management vs revascularization

Note

Clinical selection priorities

In general, favor medical management over revascularization for many patients with asymptomatic disease and use CEA preferentially in many symptomatic patients unless anatomic or physiologic risks favor CAS/TCAR. The USPSTF recommends against screening for asymptomatic carotid stenosis in the general adult population.

Preference for CEA in many symptomatic patients unless specific risks favor CAS/TCAR
Screening for asymptomatic carotid stenosis discouraged (USPSTF Grade D)
Selection of asymptomatic patients should consider life expectancy and comorbidities

Note

Evidence limitations may trigger coverage scrutiny

Evidence for TCAR is limited to nonrandomized and observational studies and systematic reviews; when evidence is limited, prior authorization requests may receive additional scrutiny and require supporting outcome data.

Limited randomized evidence for TCAR; requests may trigger additional review
Systematic reviews and registries cited as supporting data

Documentation Required

Required supporting outcomes

When submitting a prior authorization or coverage request for CAS/TCAR/CEA, include supporting perioperative outcome data (eg, 30-day stroke and death rates), registry or trial identifiers, operator credentialing/experience, and center volumes where available to demonstrate expected outcomes meet guideline benchmarks.

Submit registry or trial identifiers and perioperative outcome data (30-day stroke/death rates)
Document operator credentialing and relevant experience/volume (eg, CREST selection criteria)
Provide center-level outcomes when available

Denial Risk

No explicit authorization or denial criteria specified

This section does not create an independent automatic authorization or denial; absence of documentation or failure to meet medical necessity criteria may lead to denial. Always verify benefits and follow prior authorization procedures where required by the member's contract.

No explicit automatic authorization in this section
Lack of documentation or failure to meet Policy criteria may result in denial
Verify benefits and prior authorization requirements per contract

Described as an option for individuals defined as high risk for carotid endarterectomy (clinical or anatomic high risk)

Approach rationaleTranscervical access avoids traversing the aortic arch and incorporates neuroprotection via flow reversal

Net clinical benefit — definition regarding benefit accrual over time

Net clinical benefit definitionBenefit of stroke reduction over time that outweighs immediate periprocedural harms, requiring sufficient anticipated life expectancy for benefit to accrue

Relation to periprocedural thresholdsPeriprocedural harms are immediate while benefit accrues over years; acceptable periprocedural rates are needed to achieve net benefit

Trial-derived life-expectancy considerationTrials specify anticipated life expectancy (eg, 2–5 years depending on stenosis and symptom status) needed to realize net benefit

CREST — trial definition

CREST trial nameCarotid Revascularization Endarterectomy Versus Stenting Trial (CREST)

Scope and enrollmentEnrolled 2522 patients at 117 centers (included both symptomatic and asymptomatic patients) with selective credentialing of interventionalists

PurposeRandomized trial comparing CAS versus CEA with primary endpoints including periprocedural stroke, MI, or death and long-term ipsilateral stroke

TCAR — transcarotid artery revascularization description (device/platform)

TCAR device/platformEnroute® Transcarotid Neuroprotection System has been the primary platform used in reported TCAR nonrandomized trials

Evidence baseKey nonrandomized trials (eg, ROADSTER, ROADSTER-2, Kwolek, Kashyap) evaluated TCAR using the Enroute system

Reported outcomes contextProcedural success and composite stroke/death/MI rates reported in these trials inform comparative observational findings

CREST-2 — randomized trials program definition

CREST-2 programRandomized trials program comparing intensive medical management alone versus medical management plus CAS or plus CEA in patients with high-grade (≥70%) asymptomatic carotid stenosis

Trial design noteCREST-2 ran parallel trials: one comparing medical management vs medical management+CAS and the other medical management vs medical management+CEA

ImplicationFindings inform consideration of medical therapy first for asymptomatic high-grade stenosis

Enroute® Transcarotid Neuroprotection System (NPS) — specific device/platform used in TCAR studies

Enroute® NPS roleSpecific neuroprotection platform used to perform TCAR in several key nonrandomized trials and registries

Study examplesROADSTER and ROADSTER-2 and other series evaluated outcomes using the Enroute® Transcarotid Neuroprotection System

Evidence limitationOutcomes derived primarily from nonrandomized studies of the Enroute® system; RCT evidence is lacking

Abbreviations and recommendation grading — CAS, CEA, COR, LOE definitions

CAS abbreviationCAS = carotid artery angioplasty with stenting

CEA abbreviationCEA = carotid endarterectomy

Recommendation grading termsCOR = class of recommendation; LOE = level of evidence

TCAR — TCAR with dynamic flow reversal (alternate definition chunk)

TCAR with dynamic flow reversalTCAR incorporating dynamic flow reversal for neuroprotection during transcervical stenting

Commonly used platformDescribed in ROADSTER and related nonrandomized studies using Enroute® system

Evaluation contextEvidence primarily observational; comparative analyses vs TF-CAS and CEA available from meta-analyses and registries

CAS / CEA — definitions for carotid artery stenting and carotid endarterectomy

CAS definitionCarotid artery stenting (CAS): endovascular placement of stent(s) in the carotid artery as a revascularization strategy

CEA definitionCarotid endarterectomy (CEA): surgical removal of atherosclerotic plaque from the carotid artery

Comparative roleCAS and CEA are alternative revascularization strategies with differing perioperative risk profiles and patient selection considerations