2026 ICD-10-CM Diagnosis Code Z94.1Heart transplant status
ICD-10-CM Codes›Z00–Z99›Z77-Z99›Z94
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Risk Adjusts — HCC 221
- POA Exempt
- Not a Principal Diagnosis
Z94.1 is a billable ICD-10-CM diagnosis code for heart transplant status. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 314 through 316. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 21 closely related codes. The code is not accepted as a principal diagnosis by the Medicare Code Editor and exempt from POA reporting. Coders also document this condition as H/O: heart recipient. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Organ transplant status.
For Medicare Advantage risk adjustment, Z94.1 maps to CMS-HCC Category 221 (Heart Transplant Status/Complications) under the V28 model, adding a risk factor of about 1.053 for a community, non-dual, aged beneficiary in payment year 2026.
Code Identity
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for Z94.1.
Present on Admission (POA)Billing
Z94.1 is exempt from POA reporting on inpatient claims to general acute care hospitals. Review the other POA exempt codes in Persons with potential health hazards related to family and personal history and certain conditions influencing health status (Z77-Z99).
Medicare Risk Adjustment (HCC)Billing
Z94.1 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2026.
Source: CMS Payment Year 2026 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- H/O: heart recipient
- Transplanted heart present
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Heart Transplantation
A heart transplant removes a damaged or diseased heart and replaces it with a healthy one. The healthy heart comes from a donor who has died. It is the last resort for people with heart failure when all other treatments have failed.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert Z94.1 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About Z94.1Overview
What is the ICD-10 code for heart transplant status?
The ICD-10-CM code for heart transplant status is Z94.1 (sometimes written as Z941). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is Z94.1 (Transplanted organ and tissue status) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report heart transplant status on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does Z94.1 group to?
On inpatient claims, heart transplant status maps to MS-DRG 314, 315, 316, with relative weights from 0.6821 to 2.0852 depending on complications. Higher weights mean higher Medicare reimbursement.
Is Z94.1 a CC or MCC?
CMS lists Z94.1 as a CC (complication or comorbidity) for FY 2026. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 21 closely related codes in its exclusion list.
Can Z94.1 be a principal diagnosis?
No. The Medicare Code Editor rejects this code as a principal diagnosis because heart transplant status describes a circumstance that influences health status rather than a current illness. Report it as a secondary diagnosis.
What HCC is Z94.1?
Z94.1 (heart transplant status) maps to CMS-HCC Category 221 (Heart Transplant Status/Complications), commonly written as HCC 221, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2026. It mapped to HCC 186 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 396.
Does Z94.1 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, Z94.1 adds a risk adjustment factor of about 1.053 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.840 to 1.781 depending on the payment segment). HCC 221 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 221 category page.
