ICD-10 · PDGM grouping
I46 Cardiac arrest
All 3 codes in the I46 family, with the PDGM clinical group, comorbidity subgroup and primary-position rule CMS assigns, read from the CMS grouper crosswalk v07.2.26 and the CDC FY2027 code file.
Codes in family
3
Can lead a claim
1
Cannot lead a claim
2
What CMS assigns to I46
1 of the 3 codes groups to MMTA - Cardiac and Circulatory; 2 are assigned no clinical group. None of the 3 is assigned a comorbidity subgroup. 1 of the 3 can lead a claim. CMS attaches a code-first note to 2 of the 3.
Code first
CMS grouper convention 12, on I46.2, I46.8. Code first:
- underlying disease
Every code in I46
Descriptions are CDC’s FY2027 wording; where CMS’s grouper abbreviates one, its form is shown beneath.
| Code | Description | Primary position | Clinical group | Comorbidity subgroup |
|---|---|---|---|---|
| I46.2 | Cardiac arrest due to underlying cardiac condition | Cannot lead a claimUnacceptable principal diagnosis, code is not reportable as principal diagnosis | None | None |
| I46.8 | Cardiac arrest due to other underlying condition | Cannot lead a claimUnacceptable principal diagnosis, code is not reportable as principal diagnosis | None | None |
| I46.9 | Cardiac arrest, cause unspecified | Can lead a claim | H | None |
Sources: CMS HH PPS Grouper Software v07.2.26, effective 2026-10-01, for the clinical group, comorbidity subgroup, code-first conventions and primary-position flags; CDC NCHS ICD-10-CM FY2027 code descriptions for the family title and code wording. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.
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