2026 ICD-10-CM Diagnosis Code I42Cardiomyopathy

ICD-10-CM Codes›I00–I99›I30-I5A›I42

ICD-10-CM I42
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

I42 is a non-billable ICD-10-CM category code for cardiomyopathy, so it cannot be submitted on claims. Use a more specific code from this category instead, such as I42.0, I42.1, I42.2, and I42.3.

Code Identity

ICD-10-CM Code
I42
Billable Status
No — Non-Billable Category
Code Describes
Cardiomyopathy
Chapter
I30-I5A
Other forms of heart disease

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI30-I5AOther forms of heart disease
CategoryI42Cardiomyopathy
This CodeI42Cardiomyopathy

Specific Coding for CardiomyopathyOverview

Non-specific codes like I42 require more characters. Use one of these billable codes instead:

  • Use I42.0 for Dilated cardiomyopathy

  • Use I42.1 for Obstructive hypertrophic cardiomyopathy

  • Use I42.2 for Other hypertrophic cardiomyopathy

  • Use I42.3 for Endomyocardial (eosinophilic) disease

  • Use I42.4 for Endocardial fibroelastosis

  • Use I42.5 for Other restrictive cardiomyopathy

  • Use I42.6 for Alcoholic cardiomyopathy

  • Use I42.7 for Cardiomyopathy due to drug and external agent

  • Use I42.8 for Other cardiomyopathies

  • Use I42.9 for Cardiomyopathy, unspecified

Tabular List NotesGuidance

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

Includes

  • myocardiopathy

Code First

  • pre-existing cardiomyopathy complicating pregnancy and puerperium O99.4

Type 2 Excludes

  • ischemic cardiomyopathy I25.5
  • peripartum cardiomyopathy O90.3
  • ventricular hypertrophy I51.7

Patient EducationClinical

Cardiomyopathy

Cardiomyopathy is the name for diseases of the heart muscle. These diseases enlarge your heart muscle or make it thicker and more rigid than normal. In rare cases, scar tissue replaces the muscle tissue.

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 I42Overview

Is I42 (Cardiomyopathy) a billable code?

No. This is a category header that groups the codes for cardiomyopathy, and headers cannot be submitted on claims. Claims for cardiomyopathy need a more specific code from this category, such as I42.0, I42.1, and I42.2.