I60.4 Nontraumatic subarachnoid hemorrhage from basilar artery

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 I60.4

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.-)")

Diagnosis Index entries for I60.4

• Hemorrhage, hemorrhagic (concealed) › intracranial (nontraumatic) › subarachnoid (nontraumatic) (from) › intracranial (cerebral) artery › basilar

Nearby codes

• I60.2 Nontraumatic subarachnoid hemorrhage from anterior communicating artery
• I60.3 Nontraumatic subarachnoid hemorrhage from posterior communicating artery
• I60.30 Nontraumatic subarachnoid hemorrhage from unspecified posterior communicating artery
• I60.31 Nontraumatic subarachnoid hemorrhage from right posterior communicating artery
• I60.32 Nontraumatic subarachnoid hemorrhage from left posterior communicating artery
• I60.4 Nontraumatic subarachnoid hemorrhage from basilar artery (this code)
• I60.5 Nontraumatic subarachnoid hemorrhage from vertebral artery
• I60.50 Nontraumatic subarachnoid hemorrhage from unspecified vertebral artery
• I60.51 Nontraumatic subarachnoid hemorrhage from right vertebral artery
• I60.52 Nontraumatic subarachnoid hemorrhage from left vertebral artery
• I60.6 Nontraumatic subarachnoid hemorrhage from other intracranial arteries