I60.00 Nontraumatic subarachnoid hemorrhage from unspecified carotid siphon and bifurcation

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

Applies from I60 Nontraumatic subarachnoid hemorrhage

Excludes1 (never code together)

• syphilitic ruptured cerebral aneurysm (A52.05)

Excludes2 (not included here)

• sequelae of subarachnoid hemorrhage (I69.0-)

Use additional code

• code, if known, to indicate National Institutes of Health Stroke Scale (NIHSS) score (R29.7-)

Risk adjustment (HCC)

• CMS-HCC V28: HCC 248 — Intracranial Hemorrhage
• CMS-HCC V22: HCC 99 — Cerebral Hemorrhage
• ESRD V24: HCC 99

MS-DRG index

Defines the logic of DRG(s) 020-022 in MDC 01.

Approximate ICD-9-CM (GEMs)

• 430 Subarachnoid hemorrhage (approximate)

Code annotations containing back-references to I60.00

Back-references to I60

• Type 1 Excludes: G31.84 Mild cognitive impairment of uncertain or unknown etiology ("cerebrovascular diseases (I60-I69)")
• Code First: G46 Vascular syndromes of brain in cerebrovascular diseases ("underlying cerebrovascular disease (I60-I69)")
• Type 2 Excludes: I10 Essential (primary) hypertension ("essential (primary) hypertension involving vessels of brain (I60-I69)")
• Type 2 Excludes: I15 Secondary hypertension ("secondary hypertension involving vessels of brain (I60-I69)")
• Use Additional: I16.1 Hypertensive emergency ("cerebral hemorrhage (I60.-. I61.-, I62.-)")

Nearby codes

• I60 Nontraumatic subarachnoid hemorrhage
• I60.0 Nontraumatic subarachnoid hemorrhage from carotid siphon and bifurcation
• I60.00 Nontraumatic subarachnoid hemorrhage from unspecified carotid siphon and bifurcation (this code)
• I60.01 Nontraumatic subarachnoid hemorrhage from right carotid siphon and bifurcation
• I60.02 Nontraumatic subarachnoid hemorrhage from left carotid siphon and bifurcation
• I60.1 Nontraumatic subarachnoid hemorrhage from middle cerebral artery
• I60.10 Nontraumatic subarachnoid hemorrhage from unspecified middle cerebral artery
• I60.11 Nontraumatic subarachnoid hemorrhage from right middle cerebral artery