Cardiac Magnetic Resonance (CMR) perfusion and viability studies are among the most accurate non-invasive assessments for myocardial ischemia, scar tissue, and structural heart disease. Because CMR includes multiple technical components—cine imaging, stress perfusion, rest perfusion, late gadolinium enhancement (LGE), flow quantification, and morphology—billing requires matching the correct CPT codes, verifying documentation for each component, and ensuring payer policies are met.

CPT 75557–75564 describes cardiac MRI studies ranging from basic morphology only to full stress/rest perfusion and viability assessments. Coding must reflect the specific components performed, not simply “MRI heart.”

This guide provides detailed, practical instructions for coders, cardiologists, radiologists, practice managers, and compliance teams.

Understanding CMR Perfusion & Viability Studies

CMR perfusion evaluates myocardial blood flow at rest and/or during pharmacologic stress using gadolinium contrast. Viability imaging (LGE) identifies myocardial scar, infarction, hibernating myocardium, and fibrosis.

Key clinical uses:

• Evaluation of ischemia
• Assessment of microvascular dysfunction
• Clarifying equivocal stress testing
• Viability assessment before revascularization
• Post-MI myocardial damage assessment
• Cardiomyopathy tissue characterization

Because each component has specific CPT coding implications, the imaging protocol must be clear in documentation.

CPT Codes for CMR Perfusion & Viability (75557–75564)

Each code represents the extent of imaging and interpretation. Choosing the correct code requires inspecting the final report and verifying which sequences were completed.

75557 – Cardiac MRI Without Contrast (Morphology & Function Only)

Used when:

• Morphologic evaluation (cardiac chambers, valves, aorta) is performed
• Cine imaging for ventricular function (EF, volumes, wall motion) is included
• No contrast & no perfusion performed

Typical scenarios:

• Congenital or structural heart disease evaluation
• Pericardial disease without perfusion
• Baseline morphology before contrast CMR

Documentation must include:

• Cine imaging
• Function (EF)
• Measurements of chambers
• Valve observations

75559 – Cardiac MRI With Contrast (No Stress Perfusion)

Includes:

• All elements of 75557
• Contrast-enhanced imaging
• LGE viability imaging (scar detection)

Used when:

• Contrast is given for viability only
• No stress agent used
• No first-pass perfusion

Report must document:

• Gadolinium dose
• LGE findings (scar, infarction, fibrosis)
• Pattern typical for ischemic vs non-ischemic

75561 – Cardiac MRI with Stress Perfusion (With Contrast)

Includes:

• All morphology studies
• Pharmacologic stress perfusion
• Usually includes rest perfusion
• LGE viability may or may not be included

This code is used for:

• Ischemia assessment
• Suspected CAD
• Microvascular disease
• Assessment after abnormal stress imaging

Documentation must show:

• Stress agent (regadenoson, adenosine, dipyridamole)
• Stress protocol with vitals
• Time of contrast injections
• Perfusion defects (stress-induced vs rest)

75563 – Cardiac MRI Stress Perfusion + Viability Imaging

Includes everything in 75561 plus LGE viability.

This is the most comprehensive code.

Requires documentation of:

• Stress perfusion
• Rest perfusion
• LGE viability
• Contrast dose
• Stress protocol
• Tissue characterization

Typical clinical use:

• Combined ischemia & viability assessment
• Pre-CABG / PCI planning
• Mixed scar + ischemia evaluation

75564 – Cardiac MRI Flow Quantification (Add-on)

Used with 75557–75563 when:

• Quantitative flow imaging is performed
• Velocity mapping (VENC) is used
• Valve regurgitation/stenosis quantification is obtained
• Shunt calculations (Qp/Qs) performed

Not used alone.

Add only with:

• 75557
• 75559
• 75561
• 75563

Documentation must identify:

• Vessel studied (aorta, pulmonary artery)
• Flow velocity and direction
• Regurgitant volume/fraction
• Qp/Qs ratio

Documentation Requirements

Payers increasingly require detailed CMR documentation. Final reports should include:

1. Clinical Indication / Medical Necessity

Examples:

• Chest pain with prior nondiagnostic testing
• Known CAD requiring ischemia quantification
• Pre-revascularization viability assessment
• Cardiomyopathy of uncertain etiology
• Suspected myocarditis

2. Imaging Components Performed

Clearly list:

• Cine imaging
• Stress perfusion
• Rest perfusion
• LGE viability
• Flow mapping

3. Medication & Contrast Details

• Type & dose of contrast (gadolinium)
• Stress agent name/dose
• Contraindications addressed

4. Perfusion Findings

• Reversible perfusion defects
• Fixed defects
• Microvascular vs epicardial ischemia
• Severity & location

5. Viability Findings

• Extent & pattern of scar
• Transmurality percentages
• Infarct size
• Fibrosis patterns (HCM, DCM, amyloid, sarcoid)

6. Ventricular Volumes & EF

Quantitative measurements:

• EDV, ESV
• EF
• Stroke volume
• Mass

7. Flow Quantification (if billed)

• Regurgitant fraction
• Shunt values
• Velocity measurements

8. Final Interpretation & Recommendations

Must be signed by a qualified cardiologist/radiologist.

When Prior Authorization Is Required

Most commercial payers require prior authorization for CMR. Requirements typically include:

• Previous abnormal stress test or echo
• Indeterminate findings needing advanced imaging
• Symptoms highly suggestive of ischemia
• Pre-procedural planning
• Suspected myocarditis or infiltrative disease

Medicare does not require prior authorization, but it still reviews medical necessity.

Common denial reasons:

• Insufficient indications
• Wrong CPT code for protocol performed
• Missing contrast documentation
• Billing stress CMR without stress protocol details

Billing Rules & Compliance Tips

1. Code Based on Components Actually Performed

Example:

• If stress perfusion is performed but LGE is skipped → bill 75561, not 75563

2. Do Not Bill 75564 Alone

Flow quantification is an add-on only.

3. Avoid Upcoding

If contrast was injected but LGE images were not acquired, do not bill viability codes.

4. Contrast & Drug HCPCS

Bill contrast and stress agents separately when allowed by the payer.

5. Technical vs Professional Billing

Use modifiers:

• 26 – Interpretation only
• TC – Technical component

Facility vs non-facility rules apply.

6. Emergency CMR Billing

Emergency cases still require:

• Clear documentation
• Correct CPT assignment

Common Denials & How to Avoid Them

1. CPT Mismatch With Imaging Performed

Most frequent error:

• Billing 75563 (stress + viability), but LGE was not performed.

2. Missing Stress Agent Documentation

Auditors deny stress CMR without:

• Drug name
• Dose
• Adverse event monitoring

3. Lack of Medical Necessity

Avoid generic indications like “rule out disease.”

4. Billing Without Physician Signature

Unsigned reports are invalid.

5. Missing Contrast Dose

Required for all contrast CMR codes.

Clinical & Operational Best Practices

• Use standardized CMR reporting templates
• Clarify the imaging sequences performed
• List all components in the final report
• Use quantitative measurements wherever possible
• Document stress test vitals and ECG findings
• Ensure raw data is stored per compliance rules
• Perform periodic internal audits
• Confirm payer authorization requirements before scheduling

CMR perfusion & viability studies are high-value tests, but accurate coding and documentation are essential to avoid denials and ensure correct reimbursement.

For cardiology practices requiring structured, compliant documentation and billing workflows for advanced imaging, collaborative partners such as Global Tech Billing LLC can help maintain accurate, audit-ready CMR billing processes.

FAQs

1. What CPT codes cover CMR perfusion and viability studies?
CPT 75557–75564 cover cardiac MRI ranging from morphology only to full stress perfusion and viability imaging.

2. When is 75563 used?
When both stress perfusion and LGE viability imaging are performed in the same study.

3. Is flow quantification separately billable?
Yes, with add-on code 75564 when velocity mapping or shunt quantification is performed.

4. What documentation is required for stress CMR?
Stress agent name, dose, vitals, contrast dose, perfusion defect description, and interpretation.

5. Can CMR be billed without contrast?
Yes, using 75557 when only morphology and function are assessed without contrast.

6. Do commercial payers require authorization for CMR?
Most do; Medicare usually does not but requires medical necessity.

7. Can viability imaging be billed without stress perfusion?
Yes—use 75559 if contrast and LGE were performed but no stress component.

8. What causes most CMR denials?
Incorrect CPT selection, missing contrast/stress documentation, or insufficient medical necessity.