2026 ICD-10-CM Diagnosis Code I24.81Acute coronary microvascular dysfunction

ICD-10-CM Codes›I00–I99›I20-I25›I24

ICD-10-CM I24.81
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

I24.81 is a billable ICD-10-CM diagnosis code for acute coronary microvascular dysfunction. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). Coders also document this condition as acute microvascular ischemia of myocardium. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Coronary atherosclerosis and other heart disease.

Code Identity

ICD-10-CM Code
I24.81
Billable Status
Yes — Valid for Submission
Code Describes
Acute coronary microvascular dysfunction
Short Description
Acute coronary microvascular dysfunction
Same as the full description in the CMS dataset.
Parent Code
I24.8
Other forms of acute ischemic heart disease

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI20-I25Ischemic heart diseases
CategoryI24Other acute ischemic heart diseases
This CodeI24.81Acute coronary microvascular dysfunction

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute microvascular ischemia of myocardium
  • Acute myocardial ischemia
  • Coronary microvascular dysfunction

Tabular List NotesGuidance

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

Inclusion Terms

  • Acute (presentation of) coronary microvascular disease

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Disease, diseased
      • coronary (artery)
        • microvascular
          • acute
    • Dysfunction
      • coronary microvascular
        • acute

Clinical ClassificationClinical

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

CCSR CIR011
Coronary atherosclerosis and other heart disease
Default principal diagnosis: inpatient Yes · outpatient Yes

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.

Code History & ChangesHistory

Replacement I24.81 replaces the following previously assigned code(s):

  • I24.8 - Other forms of acute ischemic heart disease
FY 2024AddedAdded to the ICD-10-CM code setEffective October 1, 2023.
FY 2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About I24.81Overview

Is I24.81 (Other forms of acute ischemic heart disease) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report acute coronary microvascular dysfunction on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

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.