Cardiac Applications of PET Scanning

POLICY NUMBER

A.6.01.20

DESCRIPTION

Positron Emission Tomography

Positron emission tomography (PET) scans use positron-emitting radionuclide tracers, which simultaneously emit two high-energy photons in opposite directions. These photons can be simultaneously detected (referred to as coincidence detection) by a PET scanner, comprising multiple stationary detectors that encircle the thorax. Compared with single photon emission computed tomography (SPECT) scans, coincidence detection offers greater spatial resolution. PET has been investigated as an option to diagnose and evaluate patients with cardiac conditions such as coronary artery disease, left ventricular dysfunction, and cardiac sarcoidosis.

Coronary Artery Disease

Heart disease is the leading cause of death for men and women in the United States (U.S.). Heart disease is also the leading cause of death for people of most racial and ethnic groups in the U.S., including African American, American Indian, Alaska Native, Hispanic, and white men. For women from the Pacific Islands and Asian American, American Indian, Alaska Native, and Hispanic women, heart disease is second only to cancer. Coronary artery disease (CAD) is the most common type of heart disease in the U.S., killing more than 375,000 people per year. Angina is the most common symptom of CAD. Risk factors for CAD include being overweight, physical inactivity, poor diet, and smoking. A family history of heart disease also increases the risk for CAD, especially in cases where there is a family history of early onset heart disease (ie, age 50 or younger).

Myocardial Perfusion Imaging

For myocardial perfusion studies, patient selection criteria for PET includes an individual assessment of the pretest probability of coronary artery disease (CAD), based both on patient symptoms and risk factors. Patients at low-risk for CAD may be adequately evaluated with exercise electrocardiography. Patients at high-risk for CAD typically will not benefit from noninvasive assessment of myocardial perfusion; a negative test will not alter disease probability sufficiently to avoid invasive angiography. Accordingly, myocardial perfusion imaging is potentially beneficial for patients at intermediate risk of CAD (variably defined as 25% to 75% or 10% to 90% disease probability). ªRisk can be estimated using the patient's age, sex, and chest pain quality. The table below summarizes patient populations at intermediate risk for CAD.

ªIntermediate-risk ranges used in different studies may differ from the range used here. These pretest probability risk groups are based on a TEC Assessment (1995) and take into account spectrum effect. The American College of Cardiology guidelines have defined low risk as less than 10%, intermediate risk as 10% to 90%, and high risk as greater than 90%.

Individuals at Intermediate Risk for CAD According to Chest Pain Quality

Values are age or age range in years.ª Chest pain with all of the following characteristics: (1) substernal chest discomfort with characteristic quality and duration, (2) provoked by exertion or emotional stress, and (3) relieved by rest or nitroglycerin.^b Chest pain that lacks one of the characteristics of typical angina.^c Chest pain that has one or none of the typical angina characteristics.

Body habitus can limit SPECT; particularly moderate-to-severe obesity, which can attenuate tissue tracer leading to inaccurate images. In patients for whom body habitus (i.e. BMI ≥40, breast implants, prior mastectomy, chest wall deformity) or clinical conditions such as known pericardial or pleural effusion is expected to lead to suboptimal SPECT scans, PET scanning is preferred.

Among patients with CAD, myocardial perfusion imaging can be used to quantify myocardial blood flow and myocardial flow reserve (MFR). Quantitative assessment of myocardial perfusion is sensitive for detection of ischemic tissue within the myocardium, and can allow for accurate determination of risk for cardiovascular events. These quantitative measurements can also be predictive of adverse cardiovascular outcomes. For example, the presence of an abnormally low MFR can identify patients at higher risk of cardiovascular death.

Myocardial perfusion studies with PET are also useful in the diagnosis of cardiac sarcoidosis. Perfusion studies performed in patients with sarcoidosis and suspected cardiac involvement can detect presence of inflammation, fibrosis of the myocardial tissue, and function and involvement of the left and right ventricles.

Myocardial Viability

Patients selected to undergo PET scanning for myocardial viability are typically those with severe left ventricular dysfunction who are being considered for revascularization. A PET scan may determine whether the left ventricular dysfunction is related to the viable or nonviable myocardium. Patients with viable myocardium may benefit from revascularization, but those with nonviable myocardium will not. As an example, PET scanning is commonly performed in potential heart transplant candidates to rule out the presence of viable myocardium.

Radionuclide Tracers

A variety of radionuclide tracers are used for PET scanning, including fluorine 18, rubidium 82, oxygen 15, nitrogen 13, and carbon 11. Most tracers have a short half-life and must be manufactured with an on-site cyclotron. Rubidium 82 is produced by a strontium 82/rubidium 82 generator. The half-life of fluorine-18 is long enough that it can be manufactured commercially offsite and shipped to imaging centers. Radionuclides may be coupled with a variety of physiologically active molecules, such as oxygen, water, or ammonia. Fluorine 18 is often coupled with fluorodeoxyglucose to detect glucose metabolism, which in turn reflects metabolic activity, and thus viability, of the target tissue. Tracers that target the mitochondrial complex also are being developed.

A number of PET platforms have been cleared by the U.S. Food and Drug Administration (FDA) through the 510(k) process since the Penn-PET scanner was approved in 1989. These systems are intended to aid in detecting, localizing, diagnosing, staging, and restaging of lesions, tumors, disease, and organ function for the evaluation of diseases and disorders such as, but not limited to, cardiovascular disease, neurologic disorders, and cancer. The images produced by the system can aid in radiotherapy treatment planning and interventional radiology procedures.

PET radiopharmaceuticals have been evaluated and approved by the FDA for use as diagnostic imaging agents. These radiopharmaceuticals are approved for specific conditions.

In December 2009, the FDA issued guidance for Current Good Manufacturing Practice for PET drug manufacturers, and in August 2011, the FDA issued similar Current Good Manufacturing Practice guidance for small businesses. An additional final guidance document issued in December 2012 required all PET drug manufacturers and compounders to operate under an approved new drug application (NDA) or abbreviated NDA, or investigational new drug application, by December 2015.

To avoid interruption of the use of PET radiotracers already in use in clinical practice, before the issuance of specific guidance documents, the FDA made determinations of safety and effectiveness for certain uses of PET radiotracers. The following radiopharmaceuticals used with PET for cardiac-related indications were reviewed in this manner and subsequently had approved NDAs as summarized below.

Radiopharmaceuticals Approved for Use Prior to 2012 With PET for Cardiac Indicationsª

CAD: coronary artery disease; NDA: new drug application; PET: positron emission tomography.ªThis table only lists products that received an approved NDA prior to the final guidance for Current Good Manufacturing Practice for PET drug manufacturers issued by the Food and Drug Administration in December 2012.

Oncologic Applications of PET scanning  are addressed in a separate policy. Miscellaneous (Noncardiac, Nononcologic) Applications of Fluorodeoxyglucose F 18 Positron Emission Tomography  are addressed in a separate policy.

POLICY

I. For Myocardial Perfusion Studies:

Cardiac PET scanning may be considered medically necessary to assess myocardial perfusion and thus diagnose CAD in individuals with indeterminate SPECT scan, or in individuals for whom SPECT could be reasonably expected to be suboptimal in quality on the basis of body habitus (i.e. BMI ≥40, breast implants, prior mastectomy, chest wall deformity) or clinical conditions such as known pericardial or pleural effusion.

For myocardial perfusion studies, patient selection criteria for PET scans involve an individual assessment of the pretest probability of CAD, based both on patient symptoms and risk factors:

• Patients at low risk for CAD may be adequately evaluated with exercise electrocardiography.

• Patients at high risk for CAD will typically not benefit from non-invasive assessment of myocardial perfusion.

• A negative test will not alter disease probability sufficiently to avoid invasive angiography.

• Myocardial perfusion imaging is potentially beneficial for patients at intermediate risk of CAD (approximately 25% to 75% disease prevalence).

The risk can be estimated using the patient's age, sex, and chest pain quality. The range for intermediate risk can vary.

The following table summarizes a characterization for patient populations at intermediate risk for CAD:

II.For Myocardial Viability:

Cardiac PET scanning may be considered medically necessary to assess the myocardial viability in individuals with severe left ventricular dysfunction as a technique to determine candidacy for a revascularization procedure (e.g., PET scans are commonly performed in potential heart transplant candidates to rule out the presence of viable myocardium).

III. Diagnosis of Cardiac Sarcoidosis

Cardiac PET scanning may be considered medically necessary for diagnosing cardiac sarcoidosis in individuals who are unable to undergo magnetic resonance imaging (MRI) scanning. Examples of individuals who are unable to undergo MRI include, but are not limited to, individuals with pacemakers, automatic implanted cardioverter-defibrillators (AICDs), or other metal implants.

IV. Quantification of Myocardial Blood Flow

Cardiac PET scanning is investigational for quantification of myocardial blood flow for cardiac event risk stratification in individuals diagnosed with CAD.

POLICY EXCEPTIONS

None

POLICY GUIDELINES

The coverage guidelines outlined in the Medical Policy Manual should not be used in lieu of the Member’s specific benefit plan language.

Medically Necessary is defined as those services, treatments, procedures, equipment, drugs, devices, items or supplies furnished by a covered Provider that are required to identify or treat a Member's illness, injury or Mental Health Disorders, and which Company determines are covered under this Benefit Plan based on the criteria as follows in A through D:

A.  consistent with the symptoms or diagnosis and treatment of the Member's condition, illness, or injury; and

B.  appropriate with regard to standards of good medical practice; and

C.  not solely for the convenience of the Member, his or her Provider; and

D.  the most appropriate supply or level of care which can safely be provided to Member. When applied to the care of an Inpatient, it further means that services for the Member's medical symptoms or conditions require that the services cannot be safely provided to the Member as an Outpatient.

For the definition of medical necessity, “standards of good medical practice” means standards that are based on credible scientific evidence published in peer-reviewed medical literature generally recognized by the relevant medical community, and physician specialty society recommendations, and the views of medical practitioners practicing in relevant clinical areas and any other relevant factors. BCBSMS makes no payment for services, treatments, procedures, equipment, drugs, devices, items or supplies which are not documented to be Medically Necessary. The fact that a Physician or other Provider has prescribed, ordered, recommended, or approved a service or supply does not in itself, make it Medically Necessary.

Investigative is defined as the use of any treatment procedure, facility, equipment, drug, device, or supply not yet recognized as a generally accepted standard of good medical practice for the treatment of the condition being treated and; therefore, is not considered medically necessary. For the definition of Investigative, “generally accepted standards of medical practice” means standards that are based on credible scientific evidence published in peer-reviewed medical literature generally recognized by the relevant medical community, and physician specialty society recommendations, and the views of medical practitioners practicing in relevant clinical areas and any other relevant factors. In order for equipment, devices, drugs or supplies [i.e, technologies], to be considered not investigative, the technology must have final approval from the appropriate governmental bodies, and scientific evidence must permit conclusions concerning the effect of the technology on health outcomes, and the technology must improve the net health outcome, and the technology must be as beneficial as any established alternative and the improvement must be attainable outside the testing/investigational setting.

POLICY HISTORY

11/18/2009: Policy added as a result of the decision to separate the Positron Emission Tomography (PET) medical policy into application specific policies, this one addressing cardiac applications only. Upon creation of this separate policy, cardiac applications have been revised as outlined: The Policy Description Section revised for a clearer understanding of PET specific to cardiac applications, Policy Statement Section revised to add diagnosing CAD to medically necessary implications for myocardial perfusion studies, and added a guideline for CAD risk factors, Policy Coding Section updated to include Covered Codes specific to cardiac applications for PET, and added non-Covered Codes Table.

04/20/2010: Policy reviewed. No changes to policy description; statement unchanged. Added additional patient selection criteria to the Policy Guidelines section. Minor typographical errors corrected.

08/23/2011: The first policy statement was revised to change "in patients who may be prone to artifact that could lead to an indeterminate test, such as severely obese (BMI>35 kg/m2) patients" to "in patients for whom SPECT could be reasonably expected to be suboptimal in quality on the basis of body habitus." Added medically necessary policy statement regarding diagnosis of cardiac sarcoidosis.

09/25/2012: Policy reviewed; no changes.

05/07/2013: Removed ICD-9 procedure code 87.42 from the Code Reference section.

11/06/2013: Policy reviewed; no changes.

10/30/2014: Policy reviewed; description updated. Policy statement unchanged.

08/25/2015: Code Reference section updated for ICD-10.

03/29/2016: Policy description updated. Added the following policy statement: Cardiac PET scanning is investigational for quantification of myocardial blood flow in patients diagnosed with CAD. Policy guidelines updated to add section headings and information regarding SPECT scanning. Added medically necessary and investigative definitions.

05/31/2016: Policy number A.6.01.20 added.

12/30/2016: Code Reference section updated to add new 2017 HCPCS code A9598.

10/01/2017: Revised code description for ICD-10 diagnosis code I50.1, effective 10/01/2017.

10/16/2017: Policy description updated regarding myocardial perfusion imaging, myocardial viability, and cardiac PET and SPECT scans. Policy statements unchanged.

12/22/2017: Code Reference section updated to add new 2018 CPT code 0482T, effective 01/01/2018.

10/03/2018: Policy description updated regarding myocardial perfusion imaging. Policy statements unchanged.

10/21/2019: Policy statements unchanged. Policy Guidelines revised to remove information regarding myocardial perfusion imaging and myocardial viability, as both are discussed in the policy description.

12/16/2019: Policy revised to update language related to body habitus (i.e. BMI ≥40, breast implants, prior mastectomy, chest wall deformity) and clinical conditions when PET scanning is preferred to SPECT. This policy revision will become effective 01/01/2020. Sources updated.

12/19/2019: Code Reference section updated to add new CPT codes 78429, 78430, 78431, 78432, 78433, 78434, and 78835. Revised code descriptions for CPT codes 78459, 78491, and 78492. Effective 01/01/2020.

10/14/2020: Policy description updated regarding myocardial perfusion imaging and to remove information regarding advantages and disadvantages of Cardiac PET and SPECT. Policy statement revised to state that cardiac PET scanning is investigational for quantification of myocardial blood flow for cardiac event risk stratification in patients diagnosed with CAD.

12/30/2021: Policy reviewed. Policy statements unchanged. Policy Guidelines updated to change "Nervous/Mental Conditions" to "Mental Health Disorders" and "Medically Necessary" to "medical necessity." Code Reference section updated to remove deleted CPT code 0482T.

11/29/2022: Policy description updated regarding coronary artery disease and radiopharmaceuticals. Policy statements updated to change "patients" to "individuals" and "diagnosis of cardiac sarcoidosis" to "diagnosing cardiac sarcoidosis."

10/11/2023: Policy description updated regarding coronary artery disease. Policy statements updated to change "patients" to "individuals."

12/10/2024: Policy reviewed; no changes.

02/17/2025: Code Reference section updated to remove ICD-9 diagnosis codes 414.00, 414.01, 414.02, 414.03, 414.04, 414.05, 414.06, 414.07 and ICD-10 diagnosis codes I25.10 - I25.119 and I25.700 - I25.812.

04/01/2025: Code Reference section updated to add new HCPCS code A9611, effective 04/01/2025.

SOURCE(S)

1. AIM Specialty Health. Clinical Appropriateness Guidelines: Advanced Imaging Appropriate Use Criteria: Imaging of the Heart, Effective Date: June 29, 2019.

2. Blue Cross Blue Shield Association policy # 6.01.20

CODE REFERENCE

This may not be a comprehensive list of procedure codes applicable to this policy. 

The code(s) listed below are ONLY medically necessary if the procedure is performed according to the "Policy" section of this document. 

A PET scan essentially involves 3 separate activities:1. Manufacture of the radiopharmaceutical, which may be manufactured on site or manufactured at a regional delivery center with delivery to the institution performing PET2. Actual performance of the PET scan, and3. Interpretation of the results

When the radiopharmaceutical is provided by an outside distribution center, there may be an additional separate charge, or this charge may be passed through and included in the hospital bill. In addition, there will likely be an additional transportation charge for radiopharmaceuticals that are not manufactured on site.

Covered Codes 

Not Medically Necessary Codes

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