CurrentBlue Cross Blue Shield - Rhode IslandPolicy N/A

Anastomosis of Extracranial-Intracranial Arteries (EC-IC bypass)

This policy defines coverage and medical necessity criteria for EC-IC arterial bypass surgery (anastomosis of extracranial and intracranial arteries) for Blue Cross Blue Shield - Rhode Island members, including Medicare Advantage and Commercial products.

Policy Summary

PayerBlue Cross Blue Shield - Rhode Island

PolicyAnastomosis of Extracranial-Intracranial Arteries (EC-IC bypass)

Policy CodePolicy N/A

Change TypeNo material change

Effective DateDec 14, 2014

Next Review DateN/A

Key ActionObtain prior authorization via the payer's online tool for Medicare Advantage plans (recommended for Commercial products) when addressing atherosclerosis.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

1Not covered code count

Medicare+CommercialPlans referenced

1985Key trial year

Coverage and Medical Necessity Criteria

Coverage and Not Medically Necessary Criteria

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General coverage: Anastomosis of the extracranial-intracranial arteries is covered for all conditions other than atherosclerosis.

From policy medical criteria (coverage for non-atherosclerotic indications).

Not covered / Not medically necessary for ischemic cerebrovascular disease: EC-IC arterial bypass surgery is not a covered procedure for Medicare Advantage plans and not medically necessary for Commercial Products when performed as a treatment for ischemic cerebrovascular disease of the carotid or middle cerebral arteries (including treatment or prevention of strokes) because evidence is insufficient to show improvement in net health outcome.

From policy coverage statement and background evidence reference.

Atherosclerotic disease involving the carotid or middle cerebral arteries is specifically excluded from coverage. Anastomosis of the extracranial‑intracranial arteries is covered for all conditions other than atherosclerosis, and procedures performed to treat ischemic cerebrovascular disease due to atherosclerosis of the carotid or middle cerebral arteries are not covered under this policy.

Extracranial‑intracranial (EC‑IC) arterial bypass surgery is not considered reasonable and necessary when performed as a treatment for ischemic cerebrovascular disease of the carotid or middle cerebral arteries. This applies to Medicare Advantage plans as a non‑covered procedure and to Commercial Products as not medically necessary when used to treat or prevent stroke from carotid or middle cerebral artery atherosclerosis, because the evidence does not demonstrate improved net health outcomes compared with no surgical intervention.

Provider Requirements and Actions

Prior Authorization

Prior Authorization Required

Prior authorization is required for Medicare Advantage Plans and is recommended for Commercial Products. Participating providers must obtain prior authorization via the payer's web-based tool.

Applies to atherosclerosis-related procedures
Use the payer's online authorization tool for submitting requests

Note

Conservative Medical Therapy Context

Conservative medical therapy is the usual treatment context for intracranial atherosclerotic disease and includes anticoagulant (e.g., warfarin) or antiplatelet therapy (e.g., aspirin) together with medical management of cardiovascular risk factors.

Anticoagulant and antiplatelet therapy
Risk factor control (e.g., lipid management, blood pressure control)

Prior Authorization

Authorization via Online Tool

Prior authorization is required for Medicare Advantage Plans and recommended for Commercial Products; obtain authorization using the payer's online tool for participating providers.

Medicare Advantage: prior authorization required
Commercial Products: prior authorization recommended

Denial Risk

Non‑Covered Indication — Ischemic Cerebrovascular Disease (Carotid/MCA)

EC-IC arterial bypass surgery performed to treat ischemic cerebrovascular disease of the carotid or middle cerebral arteries (including for treatment or prevention of stroke) is not a covered or medically necessary indication and may be denied.

Not covered / not medically necessary when for carotid or middle cerebral artery ischemic cerebrovascular disease
Anastomosis of extracranial-intracranial arteries for other indications may be covered

Background and Rationale

An extracranial‑intracranial (EC‑IC) bypass is a neurosurgical procedure in which a craniotomy is performed and an anastomosis is created between an extracranial arterial donor and an intracranial cerebral artery with the operative goal of augmenting cerebral blood flow. The intent of the procedure is to bypass narrowed or occluded intracranial vessels to restore or improve perfusion to brain tissue.

Intracranial and extracranial atherosclerotic disease can cause transient ischemic attacks or ischemic stroke and are commonly managed with conservative medical therapy such as anticoagulant or antiplatelet medications and control of vascular risk factors. A pivotal randomized trial and subsequent evidence have not shown that EC‑IC bypass for atherosclerotic carotid or middle cerebral artery disease provides superior outcomes compared with no surgical intervention; therefore, EC‑IC bypass for that indication is not considered reasonable and necessary.

Definitions

Anastomosis of extracranial-intracranial arteries (EC-IC bypass) — definition of the surgical procedure

Procedure nameAnastomosis of extracranial-intracranial arteries (EC-IC bypass)

DescriptionSurgical craniotomy in which the physician locates extracranial arterial source vessels and anastomoses them to intracranial cerebral arteries to augment cerebral blood flow.

Key operative stepsCraniotomy, dissection and isolation of donor and recipient arteries, microvascular arterial anastomosis between extracranial and intracranial vessels.

Intended effectAugmentation of cerebral blood flow to bypass narrowed or occluded intracranial arteries.

Related CPT (policy coding)61711 — Anastomosis, arterial, extracranial-intracranial (e.g., middle cerebral/cortical) arteries (listed in policy coding as not covered for specified indication).

Intracranial atherosclerotic disease — definition/description

DefinitionNarrowing or obstruction of arteries within the skull that supply the brain caused by atheromatous plaques in the endothelium.

Clinical consequencesCan lead to transient ischemic attack (TIA), stroke, or death.

Typical diagnosis contextUsually diagnosed in patients who have presented with a TIA or stroke.

Usual treatmentUsually treated medically with anticoagulant therapy (e.g., warfarin) or antiplatelet therapy (e.g., aspirin) plus risk-factor control.

Evidence noteA randomized study by the EC/IC Bypass Study Group (1985) failed to show that EC-IC anastomosis prevents cerebral ischemia in patients with atherosclerotic disease of the carotid and middle cerebral arteries.