I23.4 Rupture of chordae tendineae as current complication following acute myocardial infarction

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 not specified as current complication following acute myocardial infarction (I51.1)

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 I23.4

Back-references to I23.4

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

Back-references to I23

• Type 2 Excludes: I74 Arterial embolism and thrombosis ("coronary embolism and thrombosis (I21-I25)")
• Type 2 Excludes: I82 Other venous embolism and thrombosis ("coronary (I21-I25)")

Diagnosis Index entries for I23.4

• Complication (s) (from) (of) › following › acute myocardial infarction NEC › chordae tendinae rupture
• Complication (s) (from) (of) › following › acute myocardial infarction NEC › rupture › chordae tendineae
• Laceration › chordae tendinae NEC › following acute myocardial infarction (current complication)
• Rupture, ruptured › chordae tendineae NEC › following acute myocardial infarction (current complication)

Nearby codes

• I23 Certain current complications following ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarction (within the 28 day period)
• I23.0 Hemopericardium as current complication following acute myocardial infarction
• I23.1 Atrial septal defect as current complication following acute myocardial infarction
• I23.2 Ventricular septal defect as current complication following acute myocardial infarction
• I23.3 Rupture of cardiac wall without hemopericardium as current complication following acute myocardial infarction
• I23.4 Rupture of chordae tendineae as current complication following acute myocardial infarction (this code)
• I23.5 Rupture of papillary muscle as current complication following acute myocardial infarction
• I23.6 Thrombosis of atrium, auricular appendage, and ventricle as current complications following acute myocardial infarction
• I23.7 Postinfarction angina
• I23.8 Other current complications following acute myocardial infarction