Alphabetic Index FY2027

I63.21

Cerebral infarction due to unspecified occlusion or stenosis of vertebral arteries

FY2027Chapter 9: Diseases of the circulatory system/I60–I69 Cerebrovascular diseases

Non-billable headerNot valid on its own. Use one of the more specific codes under it.

I63.21 is a non-billable ICD-10-CM code header for cerebral infarction due to unspecified occlusion or stenosis of vertebral arteries. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are I63.211 Cerebral infarction due to unspecified occlusion or stenosis of right vertebral artery, I63.212 Cerebral infarction due to unspecified occlusion or stenosis of left vertebral artery, I63.213 Cerebral infarction due to unspecified occlusion or stenosis of bilateral vertebral arteries and I63.219 Cerebral infarction due to unspecified occlusion or stenosis of unspecified vertebral artery. Its coding notes include a Use additional code instruction, 2 Excludes1 entries and 12 Excludes2 entries.

Use additional code

Add the listed code as a secondary code, if known.

Inherited from I63 Cerebral infarction
  • code, if applicable, to identify status post administration of tPA (rtPA) in a different facility within the last 24 hours prior to admission to current facility (Z92.82)
  • code, if known, to indicate National Institutes of Health Stroke Scale (NIHSS) score (R29.7-)
Also from chapter/block level (8 notes)
Inherited from I60–I69 Cerebrovascular diseases
  • code to identify presence of:
    • alcohol abuse and dependence (F10.-)
    • exposure to environmental tobacco smoke (Z77.22)
    • history of tobacco dependence (Z87.891)
    • hypertension (I10-I1A)
    • occupational exposure to environmental tobacco smoke (Z57.31)
    • tobacco dependence (F17.-)
    • tobacco use (Z72.0)

Excludes1

Not coded here. The listed conditions generally should not be reported together.

Inherited from I63 Cerebral infarction
  • neonatal cerebral infarction (P91.82-)
Also from chapter/block level (1 note)
Inherited from I60–I69 Cerebrovascular diseases
  • traumatic intracranial hemorrhage (S06.-)

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Inherited from I63 Cerebral infarction
  • chronic, without residual deficits (sequelae) (Z86.73)
  • sequelae of cerebral infarction (I69.3-)
Also from chapter/block level (10 notes)
Inherited from Chapter 9 Diseases of the circulatory system
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
  • systemic connective tissue disorders (M30-M36)
  • transient cerebral ischemic attacks and related syndromes (G45.-)

Includes

Further defines or gives examples of the content of the category.

Inherited from I63 Cerebral infarction
  • occlusion and stenosis of cerebral and precerebral arteries, resulting in cerebral infarction

Alphabetic Index terms

Terms the official Alphabetic Index lists for this code. 1 entry

More specific codes under I63.21 4