Alphabetic Index FY2027

I25.799

Atherosclerosis of other coronary artery bypass graft(s) with unspecified angina pectoris

FY2027Chapter 9: Diseases of the circulatory system/I20–I25 Ischemic heart diseases

BillableComplete code, valid to report
Care settingsHome Health Primary · MMTA - Cardiac and CirculatoryHospital CC

I25.799 (also written I25799) is a billable ICD-10-CM diagnosis code for atherosclerosis of other coronary artery bypass graft(s) with unspecified angina pectoris. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 56 codes in category I25 (Chronic ischemic heart disease). The Alphabetic Index lists it under 2 entries. Its coding notes include a Use additional code instruction, a Code also instruction, 4 Excludes1 entries and 11 Excludes2 entries.

Guidelines tip

From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.

These combination codes already include angina pectoris, so no separate angina code is added. The link is assumed unless the documentation says the angina is due to something else.

Guidelines I.C.9.bAtherosclerotic heart disease with angina pectorisRead the official text

Use additional code

Add the listed code as a secondary code, if known.

Inherited from I25.7 Atherosclerosis of coronary artery bypass graft(s) and coronary artery of transplanted heart with angina pectoris
  • code, if applicable, to identify:
    • coronary atherosclerosis due to calcified coronary lesion (I25.84)
    • coronary atherosclerosis due to lipid rich plaque (I25.83)
Inherited from I25 Chronic ischemic heart disease
  • code to identify:
    • chronic total occlusion of coronary artery (I25.82)
    • exposure to environmental tobacco smoke (Z77.22)
    • history of tobacco dependence (Z87.891)
    • occupational exposure to environmental tobacco smoke (Z57.31)
    • tobacco dependence (F17.-)
    • tobacco use (Z72.0)

Code also

Two codes may be needed to describe the condition. This note gives no sequencing order.

Also from chapter/block level (1 note)
Inherited from I20–I25 Ischemic heart diseases
  • the presence of hypertension (I10-I1A)

Excludes1

Not coded here. The listed conditions generally should not be reported together.

This code
  • unspecified angina pectoris without atherosclerosis of other coronary artery bypass graft(s) (I20.9)
Inherited from I25.7 Atherosclerosis of coronary artery bypass graft(s) and coronary artery of transplanted heart with angina pectoris
  • atherosclerosis of bypass graft(s) of transplanted heart without angina pectoris (I25.812)
  • atherosclerosis of coronary artery bypass graft(s) without angina pectoris (I25.810)
  • atherosclerosis of native coronary artery of transplanted heart without angina pectoris (I25.811)

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Inherited from I25 Chronic ischemic heart disease
  • non-ischemic myocardial injury (I5A)
Also from chapter/block level (10 notes)
Inherited from Chapter 9 Diseases of the circulatory system
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
  • systemic connective tissue disorders (M30-M36)
  • transient cerebral ischemic attacks and related syndromes (G45.-)

Care settings

How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.

Home Health Primary

Accepted as the primary (principal) diagnosis on a home health claim. The Home Health Grouper assigns it to the MMTA - Cardiac and Circulatory clinical group.

Source: CMS Home Health Grouper Software v07.2.26, effective October 1, 2026

Hospital CC

Counts as a complication or comorbidity (CC) when reported as a secondary diagnosis on an inpatient claim. It does not count when the principal diagnosis is one of the 9 codes in its exclusion list. Some MS-DRGs also ignore a CC or MCC that defines the DRG.

Source: CMS MS-DRG Definitions Manual v44, effective October 1, 2026, Appendix C

Alphabetic Index terms

Terms the official Alphabetic Index lists for this code. 2 entries