I05.9 — Rheumatic mitral valve disease, unspecified
Is I05.9 billable?
Yes, but I05.9 is an unspecified code. I05.9 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, I05.9 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting I05.9 — the more specific alternatives are listed below.
I05.9 at a glance
| Code | I05.9 |
|---|---|
| Description | Rheumatic mitral valve disease, unspecified |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does I05.9 group to?
I05.9 sits in MDC 05 and helps define the logic of 2 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 306Cardiac Congenital and Valvular Disorders with MCCmedical
- 307Cardiac Congenital and Valvular Disorders without MCCmedical
How is I05.9 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to I05.9. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Disease, diseased › mitral
- Endocarditis › mitral (chronic) (marantic) (nonbacterial) (thrombotic) (valvular)
- Lesion › mitral (s) (nontraumatic)
- Disease, diseased › heart › mitral
- Endocarditis › mitral › with › rheumatic fever › inactive or quiescent (chronic) (marantic) (nonbacterial) (thrombotic) (valvular)
- Fever › rheumatic › inactive or quiescent with › endocarditis › mitral (inanition) (of unknown origin) (persistent) (with chills) (with rigor)
Inclusion terms
Alternative wording in documentation that is classified to I05.9.
- Rheumatic mitral (valve) disorder (chronic) NOS
Excludes1 — never code together — inherited from I05
The conditions below can never be reported together with I05.9 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Excludes2 — not included here — inherited from Chapter 9
The conditions below are not part of I05.9, but a patient may have both at the same time. When documentation supports it, I05.9 and the excluded code may both be reported.
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
- systemic connective tissue disorders (M30-M36)
- transient cerebral ischemic attacks and related syndromes (G45.-)
How long has I05.9 existed?
I05.9 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.
Which codes are confused with I05.9?
ICD-10-CM declares these codes mutually exclusive with I05.9 — exactly one of each pair can be correct for a given encounter.