CMS PET Scan Heart Perfusion Coverage: What Billing Teams Need to Know About NCD 292

CMS has issued a modification to National Coverage Determination (NCD) 292, which governs Medicare coverage for positron emission tomography (PET) scans used for cardiac perfusion imaging. This update, effective March 12, 2026, touches one of the more nuanced areas of cardiovascular billing—where the relationship between PET and SPECT imaging directly determines whether a claim will be paid or denied. If your practice or facility bills for cardiac PET perfusion studies, understanding exactly what CMS requires is essential before submitting claims.

What CMS NCD 292 Actually Covers: Cardiac PET Perfusion Rules

The Centers for Medicare & Medicaid Services covers cardiac PET perfusion imaging under two distinct radiopharmaceutical pathways, each with its own effective date and documentation requirements. Both pathways follow the same core coverage logic, but your billing team needs to understand both to avoid claim denials.

Rubidium 82 (Rb 82) — Covered from March 14, 1995

CMS covers PET scans performed at rest or with pharmacological stress for noninvasive imaging of cardiac perfusion using the FDA-approved radiopharmaceutical Rubidium 82. Coverage applies to patients with known or suspected coronary artery disease (CAD). The study must meet at least one of two conditions:

• The PET scan is performed in place of—not in addition to—a SPECT study, or
• The PET scan is performed following a SPECT that was inconclusive, where the PET was determined necessary to decide on appropriate medical or surgical intervention.

Ammonia N-13 — Covered from October 1, 2003

The same coverage rules apply to PET perfusion imaging using FDA-approved ammonia N-13. At rest alone or rest with pharmacological stress, the study must replace SPECT or follow an inconclusive SPECT. The medical necessity standard and documentation requirements are identical to the Rb 82 pathway.

The PET vs. SPECT Replacement Rule—The Most Common Billing Error

The most critical concept in NCD 292 is the replacement rule, and it's also where claims most frequently go wrong. CMS will not pay for a cardiac PET perfusion study that is ordered as a supplemental or concurrent study alongside SPECT imaging. The policy is explicit: PET is covered when it substitutes for SPECT or when it follows a SPECT that produced inconclusive results.

An inconclusive SPECT—for NCD 292 purposes—is one whose results are equivocal, technically uninterpretable, or discordant with the patient's other clinical data. Critically, the inconclusive nature of the prior SPECT must be documented in the beneficiary's medical record. A verbal note or assumption that the test was inadequate is not sufficient. Your clinical documentation must specifically reflect why the SPECT was inconclusive and why the PET was then considered necessary for treatment planning.

This is a documentation gap that auditors will find. If your facility performs high volumes of cardiac imaging, a targeted internal audit of your PET-after-SPECT cases is worth doing before CMS does it for you.

Medical Necessity Criteria Under CMS NCD 292

To summarize the coverage criteria cleanly, CMS requires all of the following to establish medical necessity for a covered cardiac PET perfusion study:

Studies performed with rest alone or rest plus pharmacological stress both qualify, provided the above criteria are met. Note that exercise stress is not part of the pharmacological stress pathway described in this NCD—pharmacological agents are the standard here.

Historical Claims Submission Requirements You May Still Encounter

For dates of service prior to July 1, 2001, CMS required claimants to submit specific G codes on the claim form when billing cardiac PET with Rb 82. Those codes indicated the results of the PET scan and whether it followed an inconclusive prior noninvasive cardiac test. If the prior test was inconclusive, the claim also required documentation specifying the type of test performed and its inconclusive status.

Beginning July 1, 2001, standard appropriate codes replaced those legacy G codes. While most billing teams will never touch pre-2001 claims, this detail matters if you're working through old accounts receivable, responding to reopening requests, or handling RAC audit appeals on aged claims.

Cross-Referenced CMS Policies Billing Teams Should Know

CMS NCD 292 does not stand alone. The policy explicitly cross-references two related national coverage determinations your team should have on file:

• NCD for PET Scans (§220.6) — the broader PET coverage framework
• NCD for SPECT (§220.12) — the coverage rules governing the imaging modality that PET must replace or follow

Coverage decisions under NCD 292 can only be fully understood in context with these related policies. If a claim is denied and the denial cites a coverage conflict, the answer may lie in how these three NCDs interact.

Affected Codes

The policy data for NCD 292 does not list specific CPT or HCPCS codes within the NCD document itself. Billing teams should reference the CMS Medicare Coverage Database directly and consult the Claims Processing Transmittals (TN 1817 and TN 1833) for applicable billing codes. Standard cardiac PET perfusion imaging is typically reported using codes your MAC (Medicare Administrative Contractor) has mapped to this NCD—confirm current code assignments with your MAC or through your billing software's payer policy crosswalk.

No ICD-10-CM diagnosis codes are enumerated in the NCD 292 policy document. Diagnosis coding should reflect the patient's known or suspected CAD status and align with the medical necessity criteria above.

What Your Billing Team Should Do