G45.1 Carotid artery syndrome (hemispheric)

Billable ICD-10-CM code, FY2026. Acts as a Complication or Comorbidity (CC) as a secondary diagnosis.

Applies from G45 Transient cerebral ischemic attacks and related syndromes

Excludes1 (never code together)

• neonatal cerebral ischemia (P91.0)
• transient retinal artery occlusion (H34.0-)

MS-DRG index

Defines the logic of DRG(s) 061-063 in MDC 01.

Approximate ICD-9-CM (GEMs)

• 435.8 Other specified transient cerebral ischemias (approximate)

Code annotations containing back-references to G45.1

Back-references to G45

• Type 2 Excludes: I63.9 Cerebral infarction, unspecified ("transient cerebral ischemic attacks and related syndromes (G45.-)")
• Type 1 Excludes: I65 Occlusion and stenosis of precerebral arteries, not resulting in cerebral infarction ("insufficiency, NOS, of precerebral artery (G45.-)")

Diagnosis Index entries for G45.1

• Insufficiency, insufficient › arterial › carotid (hemispheric)
• Syndrome › carotid › artery (hemispheric) (internal)

Nearby codes

• G45 Transient cerebral ischemic attacks and related syndromes
• G45.0 Vertebro-basilar artery syndrome
• G45.1 Carotid artery syndrome (hemispheric) (this code)
• G45.2 Multiple and bilateral precerebral artery syndromes
• G45.3 Amaurosis fugax
• G45.4 Transient global amnesia
• G45.8 Other transient cerebral ischemic attacks and related syndromes
• G45.9 Transient cerebral ischemic attack, unspecified