ICD-10-CM 2027
ICD-10 code for cordis morbus
From the official ICD-10-CM alphabetic index entry “Morbus › cordis”. Page updated September 29, 2026.
About coding cordis morbus
The ICD-10-CM code for cordis morbus is I51.9 (Heart disease, unspecified).
Within I51, choose I51.9 (Heart disease, unspecified) only when documentation doesn't support a more specific option: cardiac septal defect, acquired (I51.0), rupture of chordae tendineae, not elsewhere classified (I51.1), rupture of papillary muscle, not elsewhere classified (I51.2), intracardiac thrombosis, not elsewhere classified (I51.3), myocarditis, unspecified (I51.4), myocardial degeneration (I51.5), Cardiomegaly (I51.7) and other ill-defined heart diseases (I51.8).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 302 (Atherosclerosis with MCC, relative weight 1.1984) and DRG 303 (Atherosclerosis without MCC, relative weight 0.6612), in MDC 05 (Diseases and Disorders of the Circulatory System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific cordis morbus codes (official index)
- valvulorum
Common questions about cordis morbus ICD-10 codes
What is the ICD-10 code for cordis morbus?
- I51.9 — Heart disease, unspecified.
Is I51.9 billable?
- Yes. I51.9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can I51.9 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict I51.9 as a principal diagnosis.
Is I51.9 a CC or MCC?
- No. I51.9 is neither a CC nor an MCC under MS-DRG v44.0.