2026 ICD-10-CM Diagnosis Code I52Other heart disorders in diseases classified elsewhere

ICD-10-CM CodesI00–I99I30-I5AI52

ICD-10-CM I52
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

I52 is a billable ICD-10-CM diagnosis code for other heart disorders 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 302 through 303. The code is a manifestation code that cannot be reported as the principal diagnosis. Coders also document this condition as diffuse disease of coronary artery. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other and ill-defined heart disease.

Code Identity

ICD-10-CM Code
I52
Billable Status
Yes — Valid for Submission
Code Describes
Other heart disorders in diseases classified elsewhere
Short Description
Other heart disorders in diseases classified elsewhere
Same as the full description in the CMS dataset.
Chapter
I30-I5A
Other forms of heart disease

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI30-I5AOther forms of heart disease
CategoryI52Other heart disorders in diseases classified elsewhere
This CodeI52Other heart disorders in diseases classified elsewhere

Code EditsBilling

Medicare Code Editor checks that affect claim validity for I52.

Manifestation codes describe the manifestation of an underlying disease, not the disease itself, and therefore should not be used as a principal diagnosis.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Diffuse disease of coronary artery
  • Disorder of heart due to systemic lupus erythematosus
  • Ectatic coronary artery
  • Luminal irregularities of coronary artery
  • Mild intimal coronary irregularities without significant stenoses
  • Restenotic lesion of coronary artery
  • Subpulmonary stenosis
  • Ulcer of artery
  • Ulcerated lesion of coronary artery

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Code First

  • underlying disease, such as:
  • congenital syphilis A50.5
  • mucopolysaccharidosis E76.3
  • schistosomiasis B65.0 B65.9

Type 1 Excludes

  • heart disease (in):
  • gonococcal infection A54.83
  • meningococcal infection A39.50
  • rheumatoid arthritis M05.31
  • syphilis A52.06

Clinical ClassificationClinical

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

CCSR CIR015
Other and ill-defined heart disease
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

Heart Diseases

Heart disease is a general term that includes many types of heart problems. It's a type of cardiovascular disease, which means heart and blood vessel disease.

The full article covers:

  • What is heart disease?
  • What are the types of heart disease?
  • What causes heart diseases?
  • Who is more likely to develop heart diseases?
  • What are the symptoms of heart disease?
  • How are heart diseases diagnosed?
  • What are the treatments for heart disease?
  • Can heart diseases be prevented?

Read the full article at MedlinePlus

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

Convert I52 to ICD-9-CMHistory

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

ICD-9-CM
429.9 Heart disease NOS
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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About I52Overview

Is I52 (Other heart disorders in diseases classified elsewhere) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other heart disorders in diseases classified elsewhere on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does I52 group to?

On inpatient claims, other heart disorders in diseases classified elsewhere maps to MS-DRG 302, 303, with relative weights from 0.6732 to 1.1966 depending on complications. Higher weights mean higher Medicare reimbursement.

Can I52 be a principal diagnosis?

No. This is a manifestation code: other heart disorders 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 I52?

Under the General Equivalence Mappings, other heart disorders in diseases classified elsewhere converts to ICD-9-CM 429.9 (heart disease NOS). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.