2026 ICD-10-CM Diagnosis Code I79.0Aneurysm of aorta in diseases classified elsewhere
ICD-10-CM Codes›I00–I99›I70-I79›I79
- Billable — Valid for Submission
- Chronic Condition
I79.0 is a billable ICD-10-CM diagnosis code for aneurysm of aorta in diseases classified elsewhere. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 299 through 301. The code is a manifestation code that cannot be reported as the principal diagnosis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Aortic; peripheral; and visceral artery aneurysms.
Code Identity
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for I79.0.
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Code First
- underlying disease
Type 1 Excludes
- syphilitic aneurysm A52.01
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists, there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation.
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Aortic Aneurysm
An aneurysm is a bulge or "ballooning" in the wall of an artery. Arteries are blood vessels that carry oxygen-rich blood from the heart to other parts of the body. If an aneurysm grows large, it can burst and cause dangerous bleeding or even death.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert I79.0 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About I79.0Overview
Is I79.0 a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report aneurysm of aorta in diseases classified elsewhere on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does I79.0 group to?
On inpatient claims, aneurysm of aorta in diseases classified elsewhere maps to MS-DRG 299, 300, 301, with relative weights from 0.7197 to 1.6327 depending on complications. Higher weights mean higher Medicare reimbursement.
Can I79.0 be a principal diagnosis?
No. This is a manifestation code: aneurysm of aorta in diseases classified elsewhere describes the manifestation of an underlying disease rather than the disease itself, so the underlying condition is sequenced first.
What is the ICD-9 equivalent of I79.0?
Under the General Equivalence Mappings, aneurysm of aorta in diseases classified elsewhere converts to ICD-9-CM 441.9 (aortic aneurysm NOS). The mapping is approximate, so confirm the match fits the documentation.
Footnotes
[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:
- The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
- The condition places limitations on self-care, independent living, and social interactions.
