I63.529 — Cerebral infarction due to unspecified occlusion or stenosis of unspecified anterior cerebral artery

BillableUnspecifiedMCC

Is I63.529 billable?

Yes, but I63.529 is an unspecified code. I63.529 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, I63.529 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting I63.529 — the more specific alternatives are listed below.

More specific alternatives

I63.529 at a glance

Code	I63.529
Description	Cerebral infarction due to unspecified occlusion or stenosis of unspecified anterior cerebral artery
Billable	Yes
Code set	ICD-10-CM FY2027
Valid for encounters	October 1, 2026 – September 30, 2027

Which MS-DRGs does I63.529 group to?

I63.529 sits in MDC 01 and helps define the logic of 2 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.

023Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis with MCC or Antineoplastic Implant or Epilepsy with Neurostimulatorsurgical
024Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis without MCCsurgical

As a secondary diagnosis, I63.529 is a major complication or comorbidity (MCC), which can move a stay into a higher-paying DRG.

How is I63.529 listed in the Alphabetic Index?

The Alphabetic Index lists these routes under I63.52, the nearest indexed parent of I63.529. Use them to find the family, then select the specific code.

Occlusion, occluded › artery › cerebral › anterior › with infarction

Excludes1 — never code together — inherited from I60-I69

The conditions below can never be reported together with I63.529 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.

traumatic intracranial hemorrhage (S06.-)

Excludes1 — never code together — inherited from I63

The conditions below can never be reported together with I63.529 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.

neonatal cerebral infarction (P91.82-)

Use additional code — inherited from I60-I69

Report an additional code alongside I63.529 to fully describe the condition. I63.529 is sequenced first.

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)

Use additional code — inherited from I63

Report an additional code alongside I63.529 to fully describe the condition. I63.529 is sequenced first.

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-)

Excludes2 — not included here — inherited from Chapter 9

The conditions below are not part of I63.529, but a patient may have both at the same time. When documentation supports it, I63.529 and the excluded code may both be reported.

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.-)

Excludes2 — not included here — inherited from I63