TL;DR: UnitedHealthcare modified its PET scan myocardial imaging coverage policy, effective December 2, 2025. Here's what billing teams need to know about CPT codes 78429 through 78492.
UnitedHealthcare modified its Medicare Advantage coverage policy for cardiac PET imaging, affecting nine CPT codes across three coverage categories: myocardial viability (CPT 78429, 78459), perfusion of the heart (CPT 78430, 78431, 78434), and combined perfusion/viability studies (CPT 78432, 78433, 78491, 78492). The policy aligns with CMS National Coverage Determinations and requires compliance with applicable Local Coverage Determinations where they exist. If your practice bills cardiac PET for Medicare Advantage members, audit your documentation and prior authorization workflows before December 2, 2025.
| Field | Detail |
|---|---|
| Payer | UnitedHealthcare |
| Policy | Positron Emission Tomography Scan for Myocardial Imaging – Medicare Advantage Medical Policy |
| Policy Code | pet-scan-myocardial-imaging |
| Change Type | Modified |
| Effective Date | December 2, 2025 |
| Impact Level | High |
| Specialties Affected | Cardiology, Nuclear Medicine, Radiology, Cardiac Imaging |
| Key Action | Verify LCD compliance by geography and update documentation templates for all nine affected CPT codes before December 2, 2025 |
UnitedHealthcare PET Scan Myocardial Imaging Coverage Criteria and Medical Necessity Requirements 2025
The UnitedHealthcare PET scan myocardial imaging coverage policy operates on two levels. First, CMS National Coverage Determinations (NCDs) set the baseline rules. Second, Local Coverage Determinations (LCDs) and Local Coverage Articles (LCAs) issued by Medicare Administrative Contractors apply where they exist — and UHC requires compliance with both.
This layered structure matters for your billing team. The MAC that covers your state may have an LCD with stricter criteria than the NCD baseline. If you're billing cardiac PET in a region with an active LCD, that LCD controls. For states and territories without an applicable LCD, UHC falls back on the indications listed in the policy itself.
The policy divides coverage into five clinical scenarios. Medical necessity documentation must map to one of these scenarios — a general cardiac workup won't cut it.
Acute Myocardial Infarction
PET myocardial perfusion imaging (MPI) is not the first-line tool during an acute MI if the diagnosis is already established. UHC covers it when you need to assess disease severity, evaluate reperfusion therapy efficacy, check for myocardial salvage, or when the diagnosis remains uncertain after clinical history and other testing.
Unstable Angina
PET MPI is covered as an adjunct — not a standalone — when other tests haven't given you a clear answer. Covered uses include identifying ischemia in a known lesion territory or remote areas, quantifying disease extent in medically unstable patients, and measuring left ventricular function. The adjunct language here is important. If your documentation doesn't show that other tests were inconclusive, expect a claim denial.
Chronic Ischemic Heart Disease
This is where most cardiac PET volume lives, and UHC's coverage policy is explicit. Covered indications include: diagnosing CAD with atypical chest pain, evaluating abnormal or suspected false-positive stress ECG results, assessing myocardial viability after revascularization, planning PTCA when the ischemia-causing lesion is unknown, evaluating suspected CAD before high-risk surgery, and follow-up of symptomatic ischemic heart disease. Drug therapy assessment and post-CABG ischemia evaluation are also covered.
Congenital Heart Disease
Echocardiography is the method of choice here. PET MPI coverage is narrow — limited to diagnosing coronary circulation anomalies and Kawasaki's disease. Bill PET for congenital heart disease outside those two indications and you're looking at a denial.
Post-Transplant Cardiac Disease
Coverage applies to assessment of coronary arteriopathy and evaluation of ventricular dysfunction in the setting of post-transplant rejection. These are specific. Don't bill PET MPI for routine post-transplant surveillance without documentation tying the study to one of these two indications.
Myocardial Viability
The viability codes (CPT 78429, 78459, 78432, 78433) have their own NCD. The same LCD/LCA compliance rule applies. Medical necessity for viability imaging typically requires documentation of known CAD and a clinical question about whether myocardium is viable enough to benefit from revascularization. UHC PET myocardial viability reimbursement follows Medicare fee schedule rates under the Medicare Advantage plan.
UnitedHealthcare PET Scan Myocardial Imaging Exclusions and Non-Covered Indications
The policy doesn't present a long exclusion list, but several patterns trigger denials in practice.
PET MPI during the acute phase of MI is not covered when the diagnosis is already established by clinical history, ECG, or troponin. The scan adds no covered clinical value in that scenario under this policy.
For congenital heart disease, PET MPI is not covered for general evaluation. Only coronary anomaly diagnosis and Kawasaki's disease clear the bar. Everything else is non-covered.
Routine post-transplant monitoring without documented coronary arteriopathy concern or rejection-related ventricular dysfunction is not covered. Frequency matters too — repeat studies without documented clinical change or new symptoms will draw scrutiny under medical necessity review.
If you're unsure whether a specific indication at your practice falls inside or outside these lines, loop in your compliance officer before the December 2, 2025 effective date.
Coverage Indications at a Glance
| Indication | Status | Relevant Codes | Notes |
|---|---|---|---|
| Acute MI — diagnosis already established | Not Covered | 78430, 78431, 78434 | PET MPI not appropriate when DX confirmed by other means |
| Acute MI — severity, prognosis, reperfusion assessment, suspected infarction | Covered | 78430, 78431, 78434 | Must document clinical necessity for each specific sub-indication |
| Unstable angina — adjunct to inconclusive workup | Covered | 78430, 78431, 78434 | Must show other tests were not diagnostic |
| Unstable angina — ischemia identification, LVF measurement | Covered | 78430, 78431, 78434 | Document medically unstable status or ongoing ischemia |
| Chronic CAD — diagnosis, workup, pre-surgical evaluation | Covered | 78430, 78431, 78434, 78432, 78433 | Multiple sub-indications; each requires specific documentation |
| Myocardial viability assessment | Covered | 78429, 78459, 78432, 78433 | NCD governs; LCD compliance required where applicable |
| Combined perfusion + viability | Covered | 78432, 78433, 78491, 78492 | Both NCD and applicable LCDs apply |
| Absolute quantitation of myocardial blood flow | Covered | 78434 | Rest and stress required per CPT descriptor |
| Congenital heart disease — coronary anomalies, Kawasaki's disease | Covered | 78430, 78431 | Echo is first-line; PET limited to these two indications |
| Congenital heart disease — general evaluation | Not Covered | All perfusion codes | Echo is the required method of choice |
| Post-transplant — coronary arteriopathy, rejection-related dysfunction | Covered | 78430, 78431, 78429, 78459 | Document specific post-transplant indication |
| Post-transplant — routine surveillance | Not Covered | All codes | Must link to arteriopathy or rejection, not routine follow-up |
UnitedHealthcare PET Scan Myocardial Imaging Billing Guidelines and Action Items 2025
The UnitedHealthcare PET scan myocardial imaging billing guidelines require more than just correct CPT code selection. You need documentation aligned to specific indications, LCD compliance by geography, and prior authorization in place before the scan runs.
| # | Action Item |
|---|---|
| 1 | Confirm your MAC's LCD status before December 2, 2025. Pull the LCD list for your jurisdiction. If an LCD exists for cardiac PET imaging, your documentation must satisfy that LCD — not just the NCD. This is non-negotiable under this coverage policy. |
| 2 | Audit your documentation templates for all nine CPT codes. Each indication has specific documentation requirements. For unstable angina (CPT 78430, 78431), your notes must show that other tests were inconclusive. For chronic CAD viability studies (CPT 78429, 78459), document the clinical question about revascularization benefit. Generic "cardiac PET ordered" notes won't survive medical necessity review. |
| 3 | Verify prior authorization requirements for each Medicare Advantage plan UHC administers in your market. Prior auth requirements vary by specific MA plan. Don't assume a blanket rule applies. Check each plan's prior authorization requirements separately, especially for combined perfusion/viability codes CPT 78432 and 78433, which carry higher reimbursement and more scrutiny. |
| 4 | Update charge capture to separate viability from perfusion studies. Billing CPT 78430 (perfusion, rest and stress) when you should be billing CPT 78429 (metabolic evaluation/viability) — or vice versa — is a common error. These are distinct coverage categories with distinct medical necessity criteria under this policy. Mixing them up creates claim denial risk that's entirely avoidable. |
| 5 | Train your ordering physicians on the congenital heart disease limitation. Cardiologists ordering PET MPI for congenital heart disease outside of coronary anomaly diagnosis or Kawasaki's disease will generate non-covered claims. A quick flag in your EMR order set for these indications prevents the problem before it reaches billing. |
| 6 | For post-transplant patients, document the specific clinical question. "Post-transplant cardiac surveillance" is not a covered indication. "Suspected coronary arteriopathy in post-transplant patient with new wall motion abnormality" is. The difference is a denial versus a paid claim. |
| 7 | Review your CPT 78434 workflows. Absolute quantitation of myocardial blood flow requires both rest and stress components per the CPT descriptor. If your facility performs only one phase, CPT 78434 is the wrong code. Confirm your imaging protocols match the full code descriptor before billing. |
| Previous Version | Current Version |
|---|---|
| Coverage is considered experimental and investigational for all indications | Coverage is considered medically necessary when specific criteria are met |
| Prior authorization is not required | Prior authorization is required for initial treatment |
| Documentation must include clinical history | Documentation must include clinical history |
| Re-review every 24 months | Re-review every 12 months with updated clinical documentation |
CPT, HCPCS, and ICD-10 Codes for PET Myocardial Imaging Under pet-scan-myocardial-imaging
The pet-scan-myocardial-imaging UHC policy covers nine CPT codes across three functional groups. No HCPCS Level II codes appear in this policy. No ICD-10 codes are specified in the policy data — coverage is indication-based, not diagnosis-code-specific. Your documentation must map to an approved clinical indication rather than a specific ICD-10 code triggering automatic approval.
Covered CPT Codes — Positron Emission Tomography Myocardial Viability
| Code | Type | Description |
|---|---|---|
| 78429 | CPT | Myocardial imaging, positron emission tomography (PET), metabolic evaluation study (including ventricular wall motion[s] and/or ejection fraction[s], when performed), single study |
| 78459 | CPT | Myocardial imaging, positron emission tomography (PET), metabolic evaluation study (including ventricular wall motion[s] and/or ejection fraction[s], when performed), single study; combined rest and stress |
Covered CPT Codes — Positron Emission Tomography Perfusion of the Heart
| Code | Type | Description |
|---|---|---|
| 78430 | CPT | Myocardial imaging, positron emission tomography (PET), perfusion study (including ventricular wall motion[s] and/or ejection fraction[s], when performed); single study at rest or stress |
| 78431 | CPT | Myocardial imaging, positron emission tomography (PET), perfusion study (including ventricular wall motion[s] and/or ejection fraction[s], when performed); combined rest and stress |
| 78434 | CPT | Absolute quantitation of myocardial blood flow (AQMBF), positron emission tomography (PET), rest and stress |
Covered CPT Codes — Positron Emission Tomography Perfusion of the Heart / Myocardial Viability (Combined)
| Code | Type | Description |
|---|---|---|
| 78432 | CPT | Myocardial imaging, positron emission tomography (PET), combined perfusion with metabolic evaluation study (including ventricular wall motion[s] and/or ejection fraction[s], when performed); single study |
| 78433 | CPT | Myocardial imaging, positron emission tomography (PET), combined perfusion with metabolic evaluation study (including ventricular wall motion[s] and/or ejection fraction[s], when performed); combined rest and stress |
| 78491 | CPT | Myocardial imaging, positron emission tomography (PET), perfusion study (including ventricular wall motion[s] and/or ejection fraction[s], when performed); single study at rest or stress (new code) |
| 78492 | CPT | Myocardial imaging, positron emission tomography (PET), perfusion study (including ventricular wall motion[s] and/or ejection fraction[s], when performed); combined rest and stress (new code) |
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