Q28.9
Congenital malformation of circulatory system, unspecified
Q28.9 (also written Q289) is a billable ICD-10-CM diagnosis code for congenital malformation of circulatory system, unspecified. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 6 codes in category Q28 (Other congenital malformations of circulatory system). The Alphabetic Index lists it under 12 entries. Its coding notes include 4 Excludes1 entries and 4 Excludes2 entries.
Guidelines tip
From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.
Chapter 17 codes can be used for life. Manifestations that are an inherent part of a specifically coded anomaly are not coded separately. A corrected malformation is reported with a personal history code.
Excludes1
Not coded here. The listed conditions generally should not be reported together.
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
Also from chapter/block level (1 note)
- inborn errors of metabolism (E70-E88)
Care settings
How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.
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 102 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 CNotes
Also from chapter/block level (1 note)
- Codes from this chapter are not for use on maternal records
Alphabetic Index terms
Terms the official Alphabetic Index lists for this code. 12 entries
- Agenesis, circulatory system, part NOS
- Anomaly, anomalous (congenital) (unspecified type), circulatory system
- Circulation, defective (lower extremity), congenital
- Circulation, embryonic
- Circulation, heart, incomplete
- Defect, defective, circulation, congenital
- Defect, defective, circulation, newborn
- Deformity, cardiovascular system, congenital
- Disease, diseased, cardiovascular (atherosclerotic), congenital
- Embryonic, circulation
- Embryonic, heart
- Malformation (congenital), circulatory system