I34
Non-Billable (Header)Nonrheumatic mitral valve disorders
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
What This Code Means
I34 is the ICD-10-CM diagnosis code for nonrheumatic mitral valve disorders. I34 sits in the ICD-10-CM chapter for diseases of the circulatory system (i00-i99), within the section covering other forms of heart disease (i30-i5a).
Header codes like I34 cannot be reported on claims directly — they organize child codes that share clinical context but the actual diagnosis must be coded to the highest level of specificity supported by the documentation. Coders should look at I34's child codes and select the one that matches the patient's documented presentation, since payers reject header codes submitted as the primary diagnosis. For risk adjustment workflows, header codes never contribute to a Medicare Advantage member's RAF score on their own; only billable child codes that happen to map to a payment HCC affect risk-adjusted plan payments.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for I34 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Excludes 1 — Do NOT code together
- mitral valve disease (I05.9)
- mitral valve failure (I05.8)
- mitral valve stenosis (I05.0)
- mitral valve disorder of unspecified cause with diseases of aortic and/or tricuspid valve(s) (I08.-)
- mitral valve disorder of unspecified cause with mitral stenosis or obstruction (I05.0)
- mitral valve disorder specified as congenital (Q23.2, Q23.9)
- mitral valve disorder specified as rheumatic (I05.-)