I09.1 Rheumatic diseases of endocardium, valve unspecified

Billable ICD-10-CM code, FY2026.

Applicable to

• Rheumatic endocarditis (chronic)
• Rheumatic valvulitis (chronic)

Excludes1 (never code together)

• endocarditis, valve unspecified (I38)

MS-DRG index

Defines the logic of DRG(s) 306-307 in MDC 05.

Approximate ICD-9-CM (GEMs)

• 397.9 Rheumatic diseases of endocardium, valve unspecified (approximate)

Code annotations containing back-references to I09.1

Back-references to I09.1

• Type 1 Excludes: I08 Multiple valve diseases ("rheumatic valve disease NOS (I09.1)")
• Type 1 Excludes: I38 Endocarditis, valve unspecified ("endocarditis specified as rheumatic (I09.1)")

Back-references to I09

• Type 1 Excludes: I01 Rheumatic fever with heart involvement ("chronic diseases of rheumatic origin (I05-I09) unless rheumatic fever is also present or there is evidence of reactivation or activity of the rheumatic process.")
• Type 2 Excludes: I51 Complications and ill-defined descriptions of heart disease ("heart disease specified as rheumatic (I00-I09)")

Diagnosis Index entries for I09.1

• Endocarditis (chronic) (marantic) (nonbacterial) (thrombotic) (valvular) › with rheumatic fever (conditions in I00) › inactive or quiescent (with chorea)
• Endocarditis (chronic) (marantic) (nonbacterial) (thrombotic) (valvular) › rheumatic (chronic) (inactive) (with chorea)
• Fever (inanition) (of unknown origin) (persistent) (with chills) (with rigor) › rheumatic (active) (acute) (chronic) (subacute) › inactive or quiescent with › endocarditis

Nearby codes

• I09 Other rheumatic heart diseases
• I09.0 Rheumatic myocarditis
• I09.1 Rheumatic diseases of endocardium, valve unspecified (this code)
• I09.2 Chronic rheumatic pericarditis
• I09.8 Other specified rheumatic heart diseases
• I09.81 Rheumatic heart failure
• I09.89 Other specified rheumatic heart diseases
• I09.9 Rheumatic heart disease, unspecified