I24.9Acute ischemic heart disease, unspecified

I24.9 is the ICD-10-CM diagnosis code for acute ischemic heart disease, unspecified. It belongs to category I24 (other acute ischemic heart diseases), block I20-I25 (ischemic heart diseases) and chapter 9 (diseases of the circulatory system). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within I24, choose I24.9 (Acute ischemic heart disease, unspecified) only when documentation doesn't support a more specific option: acute coronary thrombosis not resulting in myocardial infarction (I24.0), Dressler's syndrome (I24.1) and other forms of acute ischemic heart disease (I24.8).

Don't report I24.9 together with the conditions in its Excludes1 note: ischemic heart disease (chronic) NOS (I25.9).

As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.

In MS-DRG v44.0, it is part of the grouping logic for DRG 311 (Angina Pectoris, relative weight 0.6684), in MDC 05 (Diseases and Disorders of the Circulatory System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 411.89 (other acute and subacute forms of ischemic heart disease, other).