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CurrentAetnaPolicy 0276

Angioplasty and Stenting of Extra-Cranial and Intra-Cranial Arteries

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This clinical policy governs when angioplasty, stenting, and related endovascular or EC‑IC bypass procedures of extra‑cranial and intra‑cranial arteries are considered medically necessary, experimental/investigational, and lists applicable billing and diagnosis codes; it applies to Aetna coverage determinations and providers performing these procedures.

Policy Summary

PayerAetna

PolicyAngioplasty and Stenting of Extra-Cranial and Intra-Cranial Arteries

Policy CodePolicy 0276

Change TypeNo material change

Effective DateAug 28, 1998

Last ReviewMar 16, 2023

Next Review DateMar 14, 2024

Key ActionDocument failure of optimal medical therapy and lesion details before requesting prior authorization for angioplasty or stenting.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

03/14/2024Next Review

08/28/1998Effective

5.8%SAMMPRIS: Med Mgmt 30-day

14.7%SAMMPRIS: PTAS 30-day

2HDE approvals

Coverage Criteria and Clinical Indications

inv-16: Literature-derived clinical indications

Literature‑derived clinical indications summarize diagnoses and situations from published studies and series in which extracranial–intracranial (EC‑IC) bypass or related revascularization procedures have been used or recommended.

EC‑IC bypass (general): Historically used for patients with symptomatic atherosclerotic disease of the internal carotid or middle cerebral arteries with recurrent hemispheric ischemic events despite medical therapy; randomized trial evidence (EC/IC Bypass Study Group, 1985) did not demonstrate a benefit for routine use for ischemic cerebrovascular disease.

Hemodynamic cerebral ischemia with objective testing: Surgical bypass has been considered for patients with symptomatic internal carotid artery occlusion and documented hemodynamic insufficiency (e.g., increased oxygen extraction fraction on PET or abnormal acetazolamide challenge on xenon‑enhanced CT) — however, randomized data (Powers et al., 2011) did not show reduction in recurrent ipsilateral ischemic stroke at 2 years when bypass plus medical therapy was compared with medical therapy alone.

Selected aneurysm indications (complex/giant intracranial aneurysms): EC‑IC high‑flow bypass with parent artery occlusion may be indicated for giant or complex ICA aneurysms (petrous, cavernous, clinoid segments) or when parent vessel sacrifice is required; single‑center series report high bypass patency and acceptable outcomes but recommend individualized selection and experienced centers.

Policy Summary

PayerAetna

PolicyAngioplasty and Stenting of Extra-Cranial and Intra-Cranial Arteries

Policy CodePolicy 0276

Change TypeNo material change

Effective DateAug 28, 1998

Last ReviewMar 16, 2023

Next Review DateMar 14, 2024

Key ActionDocument failure of optimal medical therapy and lesion details before requesting prior authorization for angioplasty or stenting.

SourceLink

On This Page

Billing and Diagnosis Codes

Covered CPT Codes (selection shown)CPTCovered

0075T	Transcatheter placement of extracranial vertebral artery stent(s), including radiologic supervision and interpretation, open or percutaneous; initial vessel
0076T	Each additional vessel (List separately in addition to code for primary procedure)
36100	Introduction of needle or intracatheter, carotid or vertebral artery
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; 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
37218	Transcatheter placement of intravascular stent(s), intrathoracic common carotid artery or innominate artery, open or percutaneous antegrade approach, including angioplasty, when performed, and radiological supervision and interpretation
37246	Transluminal balloon angioplasty (except lower extremity artery(ies) for occlusive disease, intracranial, coronary, pulmonary, or dialysis circuit), open or percutaneous, including all imaging and radiological supervision and interpretation necessary to perform the angioplasty within the same artery
37247	Transluminal balloon angioplasty (paired code)
37248	Transluminal balloon angioplasty (except dialysis circuit), open or percutaneous, including all imaging and radiological supervision and interpretation necessary to perform the angioplasty within the same vein

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Intracranial procedure CPT Codes (with coverage notes)CPT

61635	Transcatheter placement of intravascular stent(s), intracranial (eg, atherosclerotic stenosis), including balloon angioplasty, if performed [not covered for prophylactic percutaneous transluminal angioplasty of intracranial arteries after aneurysmal subarachnoid hemorrhage; dual diagnosis needed - subarachnoid hemorrhage and ischemia]
61640	Balloon dilatation of intracranial vasospasm, percutaneous; initial vessel [not covered for prophylactic percutaneous transluminal angioplasty of intracranial arteries after aneurysmal subarachnoid hemorrhage; dual diagnosis needed - subarachnoid hemorrhage and ischemia]
61641	Each additional vessel in same vascular family (List separately in addition to code for primary procedure) [not covered for prophylactic percutaneous transluminal angioplasty of intracranial arteries after aneurysmal subarachnoid hemorrhage; dual diagnosis needed - subarachnoid hemorrhage and ischemia]
61642	Each additional vessel in different vascular family (List separately in addition to code for primary procedure) [not covered for prophylactic percutaneous transluminal angioplasty of intracranial arteries after aneurysmal subarachnoid hemorrhage; dual diagnosis needed - subarachnoid hemorrhage and ischemia]
61711	Anastomosis, arterial, extracranial-intracranial (eg, middle cerebral/cortical) arteries

Related HCPCS/HCPCS II codesHCPCSCovered

C1725	Catheter, transluminal angioplasty, non-laser (may include guidance, infusion/perfusion capability)
C1726	Catheter, balloon dilation, non-vascular
C1727	Catheter, balloon tissue dissector, non-vascular (insertable)
C1874	Stent, coated/covered, with delivery system [not covered for drug-eluting stents]
C1875	Stent, coated/covered, without delivery system [not covered for drug-eluting stents]
C1876	Stent, non-coated/non-covered, with delivery system
C1877	Stent, non-coated/non-covered, without delivery system
C1884	Embolization protective system
C1885	Catheter, transluminal angioplasty, laser
C2617	Stent, non-coronary, temporary, without delivery system

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ICD-10 codes covered if selection criteria are metICD-10Covered

G45.0 - G45.2, G45.8 - G45.9	Transient cerebral ischemic attacks
I63.031 - I63.039, I63.131 - I63.139, I63.231 - I63.239	Specific cerebral infarction codes referenced
I65.21 - I65.29	Occlusion and stenosis of carotid artery with or without mention of cerebral infarction
I65.01 - I65.09	Occlusion and stenosis of vertebral artery with or without mention of cerebral infarction
I67.1	Cerebral aneurysm, nonruptured
I67.5	Moyamoya disease
I67.82	Cerebral ischemia (medically refractory symptomatic delayed cerebral ischemia)
I67.841 - I67.848	Cerebral vasospasm and vasoconstriction (medically refractory symptomatic delayed cerebral ischemia)
Q28.0 - Q28.3	Arteriovenous malformation of precerebral vessels and cerebral vessels

ICD-10 codes not covered if selection criteria are metICD-10Not Covered

I66.01 - I66.9

Occlusion and stenosis of cerebral arteries, not resulting in cerebral infarction

Codes mentionedmixed

No codes listed

Referenced literature and guideline sources (no billing codes in these chunks)mixed

No codes listed

FDA device identifiers referencedmixed

H010004	Neurolink System (FDA device identifier) as cited
H050001	Wingspan Stent System with Gateway PTA Balloon Catheter (FDA identifier) as cited

Stenosis degree thresholds for coverage

Symptomatic extra‑cranial carotid stenosis>= 50% stenosis for percutaneous transluminal angioplasty with or without stent implantation

Symptomatic extra‑cranial carotid (CMS high‑risk)>70% stenosis (CMS: CAS necessary for high‑risk CEA patients with symptomatic stenosis >70%)

Asymptomatic carotid (CMS high‑risk)>80% stenosis (CMS restricted coverage for high‑risk CEA patients with asymptomatic stenosis >80%)

Extra‑cranial vertebral artery stenosis>= 50% stenosis in symptomatic persons refractory to optimal medical therapy (antithrombotics, statins, risk‑factor modification)

Intracranial stent/HDE indication threshold>= 50% stenosis for intracranial stent HDE device indications in patients refractory to pharmacotherapy

Prior Authorization, Documentation, and Workflow

Billing Rule

Procedure code coverage contingent on criteria

Procedure codes for angioplasty and stenting are covered only when the documented clinical selection criteria in the policy are met. Verify lesion location, percent stenosis, prior medical therapy, and supporting imaging in the chart before billing.

CPT/HCPCS coverage contingent on meeting policy clinical criteria and documentation (see policy CPT lists).
Confirm stenosis measurement method (duplex ultrasound confirmed by angiography if done pre-procedure) and percent stenosis in record.

Prior Authorization

Prior authorization for intra-cranial stents

Intracranial stent placement is subject to prior authorization when being considered for indications that the policy permits (e.g., treatment of medically refractory symptomatic delayed cerebral ischemia after aneurysmal SAH). For intracranial atherosclerotic stenting, coverage is limited and generally aligned with investigational device exemption (IDE) trial requirements as noted by Medicare.

Obtain prior authorization for intracranial stent procedures where policy allows.
CMS coverage for intracranial PTA/stenting applies when furnished under FDA-approved Category B IDE clinical trials — document IDE participation number and protocol.

Prior Authorization

Coverage limited to IDE trials per CMS

Coverage for intracranial PTA/stenting may be limited to enrollment and treatment under FDA-approved Category B IDE clinical trials (per CMS decision memorandum). If proposing stenting under an IDE, include trial documentation in the authorization request.

If procedure is part of an IDE/Category B trial (eg, SAMMPRIS-era protocols), submit trial protocol/IDE documentation with authorization request.
CMS guidance: PTA and stenting for intracranial stenosis covered when furnished in accordance with FDA-approved IDE protocols.

Prior Authorization

Coverage check for EC‑IC bypass (CMS NCD)

Before scheduling EC‑IC bypass, confirm current coverage determinations: CMS NCD (1991) states EC‑IC bypass is non-covered for ischemic cerebrovascular disease. Check plan-specific coverage and document hemodynamic testing if considering bypass for other indications (eg, aneurysm requiring parent artery occlusion).

EC‑IC bypass is not covered by CMS for ischemic cerebrovascular disease — verify member’s plan and document any exception rationale.
If bypass is considered for non-ischemic indications (complex aneurysm, moyamoya), include hemodynamic testing and specialty consults with the authorization request.

Prior Authorization

Prior authorization suggested for covered stents (Willis covered stent examples)

For covered stent devices (for extracranial carotid/vertebral indications and selected intracranial uses), prior authorization is suggested to ensure device-specific and indication-specific criteria are met (examples include Willis covered stent reports in the literature but require evidence and documentation).

When planning Willis or other covered intracranial stent use, include prior authorization with device details and clinical justification.
Document prior failure of medical therapy for dissections or complex lesions when proposing flow-diverting or covered stents.

Prior Authorization

Prior authorization: vertebral artery stenting

Prior authorization is required for certain vertebral and complex intracranial procedures per this policy; include trial enrollment or justification and complete clinical documentation to support medical necessity.

For vertebral artery stenting, include trial data or RCT evidence when available and document symptomatic ≥50% stenosis despite optimal medical therapy.
Submit pooled RCT or VIST/VAST/SAMMPRIS references as supporting evidence when applicable.

Note

Prior authorization requirement — consult full policy

The policy extract does not list an explicit, exhaustive administrative prior authorization code list in these chunks. Consult the full policy and Aetna program provisions for up-to-date PA forms, code lists, and submission instructions.

No explicit PA code list provided in the extract — contact Aetna authorization program for current requirements.
Use Aetna Program Provisions and online resources linked in the policy for submission portals and forms.

Denial Risk

Intracranial prophylactic TBA denial risk

Intracranial prophylactic percutaneous transluminal angioplasty (TBA) performed prophylactically after aneurysmal subarachnoid hemorrhage has been associated with procedural risk and is not supported by the evidence — such prophylactic procedures risk denial.

Prophylactic intracranial angioplasty after SAH is generally not covered; ensure procedure is for refractory symptomatic vasospasm with documentation of failed medical therapy.
Highlight prior medical treatments and the refractory nature of vasospasm in authorization requests.

Denial Risk

Insufficient evidence and safety concerns for intracranial stent insertion

Multiple evidence reviews and guideline assessments cited in the policy express insufficient evidence and safety concerns regarding routine intracranial stent insertion (lack of RCTs early on, registry biases, high peri-procedural morbidity/mortality). Documented uncertainty necessitates careful case selection and strong supporting documentation.

Cochrane, NICE, and CMS reviews highlight inadequate evidence and potential serious adverse events (death, stroke, dissection, vessel rupture, restenosis).
Registry data have limitations; include long-term follow-up and objective outcome measures to support requests.

Denial Risk

Evidence limits for EC-IC bypass (worse outcomes in randomized trials)

Evidence limitations for EC‑IC bypass are noted (randomized trials failing to show benefit and concerns about worse outcomes). These limitations should be cited in authorization discussions and decision-making.

EC‑IC bypass trials (EC/IC Bypass Study, later RCTs) did not demonstrate benefit for ischemic cerebrovascular disease — include hemodynamic testing if arguing for a bypass in select cases.
NICE guidance advises against routine use for intracranial atherosclerosis due to safety concerns.

Note

No explicit denial triggers specified in this extract

No explicit administrative denial triggers or exhaustive PA denial criteria are specified in the provided extract. Clinical reviewers should rely on the policy’s medical necessity criteria, supporting evidence, and Aetna authorization program rules.

The extract does not provide specific billing denial triggers; use the full policy and plan terms to determine administrative denials.
When documentation is incomplete (eg, missing stenosis measurements or failed medical therapy evidence), expect requests to be returned or denied.

Documentation Required

Stenosis measurement documentation

Document the method and value of stenosis measurement (duplex ultrasound, angiography) and record confirmation by angiography when applicable. If pre-procedure ultrasound is used, angiographic confirmation at procedure start is required when specified.

Record percent stenosis and measurement modality in the chart.
If ultrasound used pre-procedure, include angiographic confirmation at procedure start per CMS guidance.

Documentation Required

Document medical therapy failure and lesion details

Document failure of optimal medical therapy (antithrombotics, statins, risk-factor modification) and lesion details (location, percent stenosis, vessel diameter, accessibility) when requesting authorization for revascularization.

For extracranial vertebral or carotid stenting, document ≥50% symptomatic stenosis and failure of optimal medical therapy.
For intracranial cases, document refractory status to pharmacotherapy and vessel diameter (eg, 2.5–4.5 mm) and ≥50% stenosis when applicable.

Documentation Required

Procedure and outcome documentation

Include procedure details and outcome documentation in the submission: procedural success, peri-procedural complications, follow-up imaging, modified Rankin Scale (mRS) outcomes, and registry or trial identifiers when applicable.

Provide peri-procedural and follow-up imaging reports (angiography, CTA/MRA) and clinical outcomes (mRS at follow-up intervals).
If using registry or trial data, include registry identifiers and follow-up duration.

Documentation Required

Required clinical documentation

Required clinical documentation for authorization should include: clinical indication, prior therapies tried and timing, objective stenosis measurements, hemodynamic testing if for bypass, procedural plan, device specifics, and planned follow-up imaging and outcome measures.

For bypass candidates, include hemodynamic insufficiency testing results (PET OEF, xenon CT, perfusion CT, acetazolamide challenge).
For emergent rescue therapies (ELVO), document thrombectomy attempts and rationale for rescue angioplasty/stenting.

Note

References and review history — consult full policy

References, policy review history, and effective dates are provided in the policy header and history — consult the full policy review history and citations for detailed evidentiary sources when preparing authorization materials.

Policy last reviewed: 03/16/2023; Effective: 08/28/1998; Next review: 03/14/2024.
Use the policy’s reference list (RCTs, guidelines, CMS memoranda) to support clinical rationale.

Note

Provides links to Aetna corporate resources for authorization details

Use Aetna corporate resources and program provisions for submission portals, prior authorization forms, and member-specific plan rules. Links and corporate resources are listed in the policy Additional Information section.

Aetna Program Provisions and online authorization portals should be used for PA submission.
Contact Aetna provider services or utilize the Aetna website links listed in the policy for up-to-date forms and instructions.

Step Therapy

Attempt optimal medical therapy first

Attempt optimal medical therapy first for many indications (eg, extracranial vertebral stenosis and intracranial atherosclerotic disease) — document therapies tried and response prior to requesting revascularization.

Document antithrombotic therapy, statin use, BP and risk-factor management, and duration of therapy prior to intervention.
For intracranial stenosis, aggressive medical management is preferred over PTAS in many cases (SAMMPRIS evidence).

Step Therapy

Step therapy preference for ICAS and stepwise clinical approach

The policy and evidence favor stepwise management for intracranial atherosclerotic stenosis (favor medical therapy first) and for ELVO recommend thrombectomy first with rescue angioplasty/stenting only if necessary; include documentation of these steps in authorization requests.

For ICAS, provide evidence of failure of optimal medical therapy before endovascular therapy is considered.
For ELVO, document primary thrombectomy attempts and justify rescue angioplasty/stenting based on re-occlusion or failed recanalization.

Note

No formal step therapy requirements specified in these chunks

No explicit step-therapy sequencing requirements or administrative step definitions are provided in the extract beyond the clinical guidance noted above. Review the full policy for any plan-specific operational step-therapy rules.

The extract does not specify formal administrative step-therapy controls — clinical sequencing guidance is provided instead.
If plan-level step therapy or utilization management rules apply, follow Aetna program provisions.

Terms and Definitions

Patients at high risk for carotid endarterectomy (CEA)

Definition (CMS) — high surgical riskSignificant comorbidities and/or anatomic risk factors rendering patient a poor candidate for CEA in the surgeon's opinion

Examples of comorbiditiesCHF class III/IV; LVEF <30%; recent MI; unstable angina

Anatomic risk factorsContralateral carotid occlusion; prior neck radiation; previous CEA with recurrent stenosis; recurrent stenosis or radical neck dissection

Symptom definitionsCarotid TIA, non‑disabling stroke (mRS <3), or transient monocular blindness (amaurosis fugax); disabling stroke (mRS >3) excluded

Humanitarian Device Exemption (HDE)

Regulatory pathwayFDA mechanism allowing marketing of devices for rare conditions (Humanitarian Device Exemption)

HDE use in intracranial stentsTwo intra‑cranial stent systems received HDEs for specific refractory intra‑cranial stenosis indications (devices intended for patients failing pharmacotherapy)

Coverage contextCMS has supported PTA and stenting for intracranial stenosis >=50% when furnished per Category B IDE or device‑specific approvals

NeuroFlo catheter

Device descriptionDual‑balloon partial aortic occlusion catheter with two independently inflatable balloons placed infra‑renal and supra‑renal

Intended effectPartial aortic occlusion to increase cerebral blood volume and augment cerebral perfusion in symptomatic vasospasm after SAH

Use considerationsApproved under HDE for patients who failed or are ineligible for medical therapy; recommended balloon inflation protocol: IR then SR to ~70% occlusion, maintained ~40 minutes

PTAS definition

DefinitionPercutaneous transluminal angioplasty and stenting of intracranial arteries (PTAS)

Clinical contextUsed to relieve intracranial arterial stenosis but randomized data (SAMMPRIS) showed higher early stroke/death with PTAS versus aggressive medical management for 70–99% stenosis

Indication nuanceMay be considered for medically refractory symptomatic cerebral vasospasm after SAH (not prophylactic) per policy

IDE Category B clinical trial

DefinitionFDA Category B IDE clinical trial — investigational device exemption under which CMS may provide coverage when procedures are furnished per approved trial protocol

Coverage implicationCMS has allowed PTA and stenting for intracranial stenosis >=50% when performed in accordance with Category B IDE protocols pending RCT evidence

PurposeTo permit evaluation of device safety/efficacy in controlled settings while enabling routine cost coverage under Medicare clinical trials policy

IPR (Intra‑procedural rupture)

DefinitionIntra‑procedural rupture (IPR) — rupture of an intracranial aneurysm occurring during endovascular treatment

Incidence (literature)Reported overall IPR incidence ~4.47% in ruptured and 1.43% in unruptured aneurysms (literature pooled); single‑center UIA series reported 0.9% IPR

Risk factorsSmaller aneurysm size, anterior communicating artery location, irregular morphology, and cardiac comorbidities associated with higher IPR risk

Transluminal balloon angioplasty (TBA)

DefinitionTransluminal balloon angioplasty (TBA) — endovascular dilation of cerebral arteries using an intraluminal balloon to relieve symptomatic focal vasospasm

Clinical roleUsed for symptomatic focal vasospasm refractory to hemodynamic augmentation and medical therapy; prophylactic TBA after SAH is not recommended

Evidence noteBalloon angioplasty considered effective for large‑vessel vasospasm at many centers but randomized outcome data are limited

sICAD

DefinitionsICAD — symptomatic intracranial atherosclerotic disease

Evidence contextsICAD has been studied with DES and other stents; pooled DES series report peri‑operative complication rates and ISR metrics but evidence remains limited

Therapeutic implicationEndovascular approaches for sICAD are generally considered investigational or limited outside trials given RCT concerns

EDAS

DefinitionEDAS — encephaloduroarteriosynangiosis, an indirect revascularization procedure promoting collateral vessel formation for moyamoya disease

Clinical useUsed to improve cerebral perfusion over time in ischemic‑type moyamoya; indirect techniques may be preferred in some centers, especially in children

Evidence baseSupport primarily from retrospective case series; randomized trials are scarce

TCAR

DefinitionTCAR — Trans‑Carotid Artery Revascularization; direct trans‑cervical carotid access stenting technique employing flow reversal neuroprotection

Technical principleDirect carotid access with dynamic flow reversal to provide continuous embolic protection and minimize aortic arch manipulation

Early outcomesObservational series report low peri‑operative stroke/death rates comparable to CEA in selected, often high‑risk, patients

Trans‑Carotid Artery Revascularization (TCAR)

DefinitionTrans‑Carotid Artery Revascularization (TCAR) — carotid stenting via direct trans‑cervical access with flow reversal system for embolic protection

Intended benefitContinuous embolic protection and reduced arch manipulation compared with transfemoral approaches

Evidence noteData primarily from observational and registry studies; randomized comparative data limited

Pipeline Embolization Device (PED)

DefinitionPipeline Embolization Device (PED) — a flow‑diverting stent used to treat intracranial aneurysms by redirecting flow away from the aneurysm sac

Outcomes for posterior circulationMeta‑analysis pooled complete obliteration ~82% with procedure‑related complication rate ~18%; efficacy and risks vary by age and aneurysm characteristics

Clinical cautionUse in posterior circulation and elderly patients associated with higher complication or incomplete occlusion rates; more long‑term data needed

Rescue therapy

DefinitionRescue therapy — endovascular interventions (eg, intra‑arterial antiplatelet infusion, angioplasty +/- stenting) performed after initial frontline thrombectomy to stabilize ICAS and prevent re‑occlusion

Clinical contextUsed during emergent large vessel occlusion (ELVO) when underlying intracranial atherosclerotic disease causes re‑occlusion or failed recanalization

Evidence statusObservational series suggest feasibility and safety but randomized trials are lacking to define optimal strategies

EC-IC bypass with parent artery occlusion (PAO)

DefinitionEC‑IC bypass with parent artery occlusion (PAO) — construction of extracranial‑to‑intracranial bypass to provide ipsilateral revascularization prior to occluding the parent vessel

IndicationUsed when parent vessel occlusion is required to treat an otherwise untreatable aneurysm and tolerance cannot be assured without revascularization

Surgical noteMay be staged with balloon test occlusion to assess ischemic tolerance; graft selection (radial artery, saphenous vein) based on required flow

Parent artery occlusion (PAO)

DefinitionParent artery occlusion (PAO) — surgical or endovascular occlusion of the parent vessel supplying an aneurysm, often performed with bypass to prevent ischemia

Use caseConsidered when definitive aneurysm exclusion cannot be achieved by clipping or coiling without sacrificing the parent vessel

DocumentationBalloon test occlusion and hemodynamic assessment often used to plan PAO with or without bypass

High-flow EC-IC bypass

DefinitionHigh‑flow EC‑IC bypass — revascularization using a large‑caliber graft (eg, saphenous vein or radial artery) to provide substantial extracranial‑to‑intracranial flow

IndicationsUsed for giant or complex ICA aneurysms, when substantial flow replacement is required before parent vessel occlusion or to restore perfusion in complex occlusive lesions

OutcomesSeries report high immediate graft patency (eg, 94.7% in series) and acceptable complication profiles in specialized centers

Cerebral vasospasm after aneurysmal subarachnoid hemorrhage

DefinitionCerebral vasospasm after aneurysmal subarachnoid hemorrhage — delayed cerebral ischemia due to vessel spasm following SAH

First‑line therapyMedical hemodynamic augmentation (eg, hypertensive therapy) and nimodipine are primary treatments; endovascular rescue considered when refractory

Endovascular roleBalloon angioplasty or intra‑arterial vasodilators used for symptomatic focal vasospasm refractory to medical therapy; prophylactic angioplasty not recommended

Extracranial-Intracranial (EC-IC) arterial bypass surgery

DefinitionExtracranial‑Intracranial (EC‑IC) arterial bypass surgery — surgical bypass connecting extracranial arteries to intracranial arteries to augment cerebral blood flow

Coverage stance (CMS)CMS NCD states EC‑IC arterial bypass is not considered reasonable and necessary when performed as treatment for ischemic cerebrovascular disease of the carotid or middle cerebral arteries

Accepted indicationsMay be medically necessary for intracranial aneurysms requiring parent artery occlusion, ischemic Moyamoya disease, documented flow‑dependent ischemia, or tumors encasing major arteries (per policy)

Angioplasty and Stenting of Extra-Cranial and Intra-Cranial Arteries

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Coverage Criteria and Clinical Indications

Billing and Diagnosis Codes

Prior Authorization, Documentation, and Workflow

Clinical Background and Rationale

Terms and Definitions

Policy Dates and Review History