US · guidance
CMS Pub. 100-04, ch. 32, § 414.4
Messages
• Contractors shall use the following messages when denying claims for TTVR submitted with
missing/incorrect ICD-10 diagnosis code (I07.1, I07.2, I08.1, I08.2, I08.3, I36.1, I36.2, Q22.8 and
Z00.6):
Claim Adjustment Reason Code (CARC) 167: This (these) diagnosis(es) is (are) not covered.
Remittance Advice Remark Code (RARC) N386: This decision was based on a National Coverage
Determination (NCD). An NCD provides a coverage determination as to whether a particular item or
service is covered. A copy of this policy is available at www.cms.gov/mcd/search.asp. If you do not have
web access, you may contact the contractor to request a copy of the NCD.
Group Code (GC) – CO (Contractual Obligation) or PR (Patient Responsibility) dependent upon liability.
Use PR when:
o On institutional claims, Occurrence Code 32 is present, and the GA modifier is not present on
any lines on the claim.
o On institutional claims, Occurrence Code 32 is present, and the GA modifier is appended to
the line item with HCPCS 0646T.
o On professional claims, the GA modifier is appended to the line item with HCPCS 0646T.
Medicare Summary Notice (MSN) 15.20: The following policies were used when we made this decision:
NCD 20.37.
Spanish Version – Las siguientes políticas fueron utilizadas cuando se tomó esta decisión: NCD 20.37.
Contractors shall Return to Provider (RTP) claims for TTVR submitted on TOB other than 11X, or when
submitted without condition code 30, or submitted without value code D4 and the 8-digit National Clinical
Trial (NCT).
Contractors shall return as unprocessable line-items on claims containing HCPCS code 0646T in a clinical
research study when billed without modifier Q0 using the following messages:
CARC 4: The procedure code is inconsistent with the modifier used.
RARC N519: Invalid combination of HCPCS modifiers.
Group Code: CO
Contractors shall return as unprocessable line-items of claims containing HCPCS code 0646T in a clinical
research study when billed without the clinical trial number using the following messages:
CARC 16: Claim/service lacks information or has submission/billing error(s).
RARC MA50: Missing/incomplete Investigational Device Exemption number or clinical trial number.
Group Code: CO
History
(Rev. 13800; Issued:05-28-26; Effective: 03-19-25; Implementation: 01-05-26)
Provenance
- Source
- cms.gov
- Retrieved
- 2026-08-25
- Edition
- iom-2026-08-25
- Content hash
aa25d68ef5d550c6a58ac2cc1be93a94d1dad510f16520def0015acb17df2242
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