ICD-10-CM 2027
ICD-10 code for congenital cardiomyopathy
From the official ICD-10-CM alphabetic index entry “Cardiomyopathy (familial) (idiopathic) › congenital”. Page updated September 29, 2026.
About coding congenital cardiomyopathy
The ICD-10-CM code for congenital cardiomyopathy is I42.4 (Endocardial fibroelastosis).
Within I42 (cardiomyopathy), I42.4 is specifically for endocardial fibroelastosis. Related codes cover dilated cardiomyopathy (I42.0), obstructive hypertrophic cardiomyopathy (I42.1), other hypertrophic cardiomyopathy (I42.2), Endomyocardial (eosinophilic) disease (I42.3), other restrictive cardiomyopathy (I42.5), alcoholic cardiomyopathy (I42.6), due to drug and external agent (I42.7), other cardiomyopathies (I42.8) and 1 more.
Code first: pre-existing cardiomyopathy complicating pregnancy and puerperium (O99.4).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
Common questions about congenital cardiomyopathy ICD-10 codes
What is the ICD-10 code for congenital cardiomyopathy?
- I42.4 — Endocardial fibroelastosis.
Is I42.4 billable?
- Yes. I42.4 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can I42.4 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict I42.4 as a principal diagnosis.
Is I42.4 a CC or MCC?
- I42.4 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.