I24.9 Acute ischemic heart disease, unspecified

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

Excludes1 (never code together)

• ischemic heart disease (chronic) NOS (I25.9)

Applies from I24 Other acute ischemic heart diseases

Excludes1 (never code together)

• angina pectoris (I20.-)
• transient myocardial ischemia in newborn (P29.4)

Excludes2 (not included here)

• non-ischemic myocardial injury (I5A)

Risk adjustment (HCC)

• CMS-HCC V28: HCC 229 — Unstable Angina and Other Acute Ischemic Heart Disease
• CMS-HCC V22: HCC 87 — Unstable Angina and Other Acute Ischemic Heart Disease
• RxHCC V08: HCC 188 — Coronary Artery Disease
• ESRD V24: HCC 87

MS-DRG index

Defines the logic of DRG(s) 311 in MDC 05.

Approximate ICD-9-CM (GEMs)

• 411.89 Other acute and subacute forms of ischemic heart disease, other (approximate)

Code annotations containing back-references to I24.9

Back-references to I24

• Type 2 Excludes: I5A Non-ischemic myocardial injury (non-traumatic) ("other acute ischemic heart diseases (I24.-)")
• 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 I24.9

• Cyanotic heart disease
• Ischemia, ischemic › heart (chronic or with a stated duration of over 4 weeks) › acute or with a stated duration of 4 weeks or less
• Ischemia, ischemic › heart (chronic or with a stated duration of over 4 weeks) › subacute
• Syndrome › coronary › acute NEC

Nearby codes

• I24.0 Acute coronary thrombosis not resulting in myocardial infarction
• I24.1 Dressler's syndrome
• I24.8 Other forms of acute ischemic heart disease
• I24.81 Acute coronary microvascular dysfunction
• I24.89 Other forms of acute ischemic heart disease
• I24.9 Acute ischemic heart disease, unspecified (this code)