2026 ICD-10-CM Diagnosis Code I25.3Aneurysm of heart
ICD-10-CM Codes›I00–I99›I20-I25›I25
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Chronic Condition
I25.3 is a billable ICD-10-CM diagnosis code for aneurysm of heart. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 314 through 316, 791, 793. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 2 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other and ill-defined heart disease.
I25.3 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 188 for payment year 2026.
This medical diagnosis code is frequently used in Cardiology medical specialties to designate conditions such selected atherosclerosis, ischemia, and infarction.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
I25.3 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model, but it maps to payment categories in the other CMS models shown below.
Source: CMS Payment Year 2026 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.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Abnormality of left atrial appendage
- Abnormality of right atrial appendage
- Acquired abnormality of mitral subvalvular apparatus
- Acquired abnormality of right cardiac ventricle
- Acquired aneurysm of left cardiac ventricle
- Acquired aneurysm of right cardiac ventricle
- Acquired subaortic aneurysm of left ventricle
- Acquired submitral aneurysm of left ventricle
- Aneurysm of heart
- Aneurysm of membranous septum
- Aneurysm of muscular septum
- Aneurysm of patch of atrioventricular septal defect
- Aneurysm of patch of left ventricular outflow tract
- Aneurysm of patch of right ventricular outflow tract
- Aneurysm of patch of ventricular septal defect
- Aortic left ventricular tunnel
- Aortic tunnel
- Aortico-left ventricular tunnel with intracardiac aneurysm of septal portion
- Apical hypertrophic cardiomyopathy with aneurysm
- Arterial obstruction due to thrombotic embolism from aneurysm of ventricle
- Atrial aneurysm
- Atrial septal aneurysm
- Coronary fistulae from right ventricle
- Left atrial appendage aneurysm
- Left ventricular aneurysm
- Postprocedural left ventricular aneurysm
- Postprocedural right ventricular aneurysm
- Right atrial appendage aneurysm
- Right ventricular aneurysm
- Ventricular aneurysm
- Ventricular aneurysm due to and following acute myocardial infarction
- Ventricular septal aneurysm
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Mural aneurysm
- Ventricular aneurysm
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Left Ventricular Aneurysm
a bulge or ballooning in the wall of the left ventricle of the heart.Ventricular Aneurysm
a bulge or ballooning in the wall of the ventricle of the heart. (acc)Ventricular Aneurysm Resection|VENTRICULAR ANEURYSM RESECTION
cardiac surgical procedure performed for the removal of an aneurysm from the ventricular wall.
Patient EducationClinical
Aneurysms
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 I25.3 to ICD-9-CMHistory
Code HistoryHistory
Questions About I25.3Overview
What is the ICD-10 code for aneurysm of heart?
The ICD-10-CM code for aneurysm of heart is I25.3 (sometimes written as I253). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is I25.3 (Chronic ischemic heart disease) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report aneurysm of heart on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does I25.3 group to?
When aneurysm of heart is the principal diagnosis on an inpatient stay, it groups to MS-DRG 314, 315, 316, 791, 793, with relative weights from 0.6821 to 4.1696 depending on complications. Higher weights mean higher Medicare reimbursement.
Is I25.3 a CC or MCC?
CMS lists I25.3 as a CC (complication or comorbidity) for FY 2026. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 2 closely related codes in its exclusion list.
What is the ICD-9 equivalent of I25.3?
Under the General Equivalence Mappings, aneurysm of heart converts to ICD-9-CM 414.10 (aneurysm of heart) and 414.19 (aneurysm of heart NEC). The mapping is approximate, so confirm the match fits the documentation.
Does I25.3 risk-adjust for Medicare Advantage payment?
Not for Medicare Advantage: I25.3 maps to no category in the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 188 (Coronary Artery Disease).
