I51.1 Rupture of chordae tendineae, not elsewhere classified

Billable ICD-10-CM code, FY2026. Acts as a Major Complication or Comorbidity (MCC) as a secondary diagnosis.

Excludes1 (never code together)

• rupture of chordae tendineae as current complication following acute myocardial infarction (I23.4)

Applies from I51 Complications and ill-defined descriptions of heart disease

Excludes2 (not included here)

• heart disease specified as rheumatic (I00-I09)

Risk adjustment (HCC)

• CMS-HCC V28: HCC 229 — Unstable Angina and Other Acute Ischemic Heart Disease
• CMS-HCC V22: HCC 86 — Acute Myocardial Infarction
• RxHCC V08: HCC 188 — Coronary Artery Disease
• ESRD V24: HCC 86

MS-DRG index

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

Approximate ICD-9-CM (GEMs)

• 429.5 Rupture of chordae tendineae (approximate)

Code annotations containing back-references to I51.1

Back-references to I51.1

• Type 1 Excludes: I23.4 Rupture of chordae tendineae as current complication following acute myocardial infarction ("rupture of chordae tendineae not specified as current complication following acute myocardial infarction (I51.1)")

Diagnosis Index entries for I51.1

• Laceration › chordae tendinae NEC
• Rupture, ruptured › chordae tendineae NEC

Nearby codes

• I51 Complications and ill-defined descriptions of heart disease
• I51.0 Cardiac septal defect, acquired
• I51.1 Rupture of chordae tendineae, not elsewhere classified (this code)
• I51.2 Rupture of papillary muscle, not elsewhere classified
• I51.3 Intracardiac thrombosis, not elsewhere classified
• I51.4 Myocarditis, unspecified
• I51.5 Myocardial degeneration
• I51.7 Cardiomegaly