2026 ICD-10-CM Diagnosis Code I23Certain current complications following ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarction (within the 28 day period)

ICD-10-CM Codes›I00–I99›I20-I25›STEMI

ICD-10-CM I23
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

I23 is a non-billable ICD-10-CM category code for certain current complications following ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarction (within the 28 day period), so it cannot be submitted on claims. Use a more specific code from this category instead, such as I23.0, I23.1, I23.2, and I23.3.

Code Identity

ICD-10-CM Code
I23
Billable Status
No — Non-Billable Category
Code Describes
Certain current complications following ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarction (within the 28 day period)
Chapter
I20-I25
Ischemic heart diseases

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI20-I25Ischemic heart diseases
CategorySTEMICertain current complications following ST elevation and non-ST elevation (NSTEMI) myocardial infarction (within the 28 day period) (I23)
This CodeI23Certain current complications following ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarction (within the 28 day period)

Specific Coding for Certain crnt comp fol STEMI & NSTEMI mocard infrc <= 28 dayOverview

Non-specific codes like I23 require more characters. Use one of these billable codes instead:

  • Use I23.0 for Hemopericardium as current complication following acute myocardial infarction

  • Use I23.1 for Atrial septal defect as current complication following acute myocardial infarction

  • Use I23.2 for Ventricular septal defect as current complication following acute myocardial infarction

  • Use I23.3 for Rupture of cardiac wall without hemopericardium as current complication following acute myocardial infarction

  • Use I23.4 for Rupture of chordae tendineae as current complication following acute myocardial infarction

  • Use I23.5 for Rupture of papillary muscle as current complication following acute myocardial infarction

  • Use I23.6 for Thrombosis of atrium, auricular appendage, and ventricle as current complications following acute myocardial infarction

  • Use I23.7 for Postinfarction angina

  • Use I23.8 for Other current complications following acute myocardial infarction

Patient EducationClinical

Heart Attack

Each year almost 800,000 Americans have a heart attack. A heart attack happens when blood flow to the heart suddenly becomes blocked. Without the blood coming in, the heart can't get oxygen. If not treated quickly, the heart muscle begins to die.

Read the full article at MedlinePlus

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

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 I23Overview

Is I23 a billable code?

No. This is a category header that groups the codes for certain current complications following ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarction (within the 28 day period), and headers cannot be submitted on claims. Claims for certain current complications following ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarction (within the 28 day period) need a more specific code from this category, such as I23.0, I23.1, and I23.2.