2027 ICD-10-CM Diagnosis Code I60.02Nontraumatic subarachnoid hemorrhage from left carotid siphon and bifurcation

ICD-10-CM Codes›I00–I99›I60-I69›I60

ICD-10-CM I60.02
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

I60.02 is a billable ICD-10-CM diagnosis code for nontraumatic subarachnoid hemorrhage from left carotid siphon and bifurcation. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 20 through 24, 64 through 66, 791, 793. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 306 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Acute hemorrhagic cerebrovascular disease.

For Medicare Advantage risk adjustment, I60.02 maps to CMS-HCC Category 248 (Intracranial Hemorrhage) under the V28 model, adding a risk factor of about 0.239 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
I60.02
Billable Status
Yes — Valid for Submission
Code Describes
Nontraumatic subarachnoid hemorrhage from left carotid siphon and bifurcation
Short Description
Ntrm subarach hemorrhage from left carotid siphon and bifurc
Parent Code
Nontraumatic subarachnoid hemorrhage from carotid siphon and bifurcation

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI60-I69Cerebrovascular diseases
CategoryI60Nontraumatic subarachnoid hemorrhage
This CodeI60.02Nontraumatic subarachnoid hemorrhage from left carotid siphon and bifurcation

Medicare Risk Adjustment (HCC)Billing

I60.02 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.

CMS-HCC V28 Category (Payment Model)
HCC 248— Intracranial Hemorrhage
Payment HCC · PY 2027 one of 53 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.239
community, non-dual, aged · ranges 0.081–0.377 across segments
Hierarchy
Supersedes HCC 249
less severe related categories are not paid alongside HCC 248
Prior Model (CMS-HCC V24)
HCC 99
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 99 · ESRD (V21): HCC 99 · ESRD (V24): HCC 99
ESRD V21 weights: 0.078 dialysis, 0.105–0.252 functioning graft · ESRD V24 weights: 0.062 dialysis, 0.082–0.438 functioning graft
Part D (RxHCC)
Not mapped
I60.02 does not risk-adjust in the RxHCC prescription drug model

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to I60.02: its own notes plus those printed at I60, block I60-I69, and Chapter 9. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From I60 Nontraumatic subarachnoid hemorrhage applies to 18 codes
  • syphilitic ruptured cerebral aneurysm (A52.05)
From Block I60-I69 Cerebrovascular diseases applies to 410 codes
  • traumatic intracranial hemorrhage (S06.-)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From I60 Nontraumatic subarachnoid hemorrhage applies to 18 codes
  • sequelae of subarachnoid hemorrhage (I69.0-)
From Chapter 9 (I00-I99) Diseases of the circulatory system applies to 1,433 codes
  • 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.-)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From I60 Nontraumatic subarachnoid hemorrhage applies to 18 codes
  • code, if known, to indicate National Institutes of Health Stroke Scale (NIHSS) score (R29.7-)
From Block I60-I69 Cerebrovascular diseases applies to 410 codes
  • 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)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name I60.02, its category, or a range that includes it.

Code First 1

These codes say to code first a condition named in the note, and I60.02 is one of the conditions named.

  • R29.7 National Institutes of Health Stroke Scale (NIHSS) score
    the type of cerebral infarction (I60.-, I61.-, I62.-, I63.-) names I60.-, which includes this code

Code Also 1

These codes say I60.02 may also be needed to fully describe the condition. The note gives no sequencing direction.

  • I16.1 Hypertensive emergency
    cerebral hemorrhage (I60.-. I61.-, I62.-) names I60.-, which includes this code

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR CIR021
Acute hemorrhagic cerebrovascular disease
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Hemorrhagic Stroke

A stroke happens when there is a loss of blood flow to part of the brain. Your brain cells cannot get the oxygen and nutrients they need from blood, and they start to die within a few minutes. This can cause lasting brain damage, long-term disability, or even death.

The full article covers:

  • What is a hemorrhagic stroke?
  • What are the types of hemorrhagic stroke?
  • What causes hemorrhagic stroke?
  • What are the symptoms of a hemorrhagic stroke?
  • How is a hemorrhagic stroke diagnosed?
  • How is hemorrhagic stroke treated?
  • Can a hemorrhagic stroke be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert I60.02 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
430 Subarachnoid hemorrhage
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About I60.02Overview

Is I60.02 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report nontraumatic subarachnoid hemorrhage from left carotid siphon and bifurcation on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does I60.02 group to?

When nontraumatic subarachnoid hemorrhage from left carotid siphon and bifurcation is the principal diagnosis on an inpatient stay, it groups to MS-DRG 793, 791, 24, 64, 22, 23, 65, 21, 20, 66, with relative weights from 0.6770 to 7.9594 depending on complications. Higher weights mean higher Medicare reimbursement.

Is I60.02 a CC or MCC?

CMS lists I60.02 as an MCC (major complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 306 closely related codes in its exclusion list.

Can I60.02 be reported with A52.05?

Not as a rule. The Excludes1 note at I60, which applies to I60.02, lists "syphilitic ruptured cerebral aneurysm (A52.05)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

Does I60.02 need an additional code?

When the condition applies, yes. The Use Additional Code note at I60, which applies to I60.02, reads: code, if known, to indicate National Institutes of Health Stroke Scale (NIHSS) score (R29.7-). The additional code is reported after I60.02.

What HCC is I60.02?

I60.02 (nontraumatic subarachnoid hemorrhage from left carotid siphon and bifurcation) maps to CMS-HCC Category 248 (Intracranial Hemorrhage), commonly written as HCC 248, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 99 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. It does not map to any RxHCC in the Part D prescription drug model.

Does I60.02 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, I60.02 adds a risk adjustment factor of about 0.239 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.081 to 0.377 depending on the payment segment). HCC 248 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 248 category page.