Cardiac imaging techniques include coronary catheterization, echocardiogram, and intravascular ultrasound, cardiac positron emission tomography (PET) scan, cardiac computed tomography (CT) and cardiac magnetic resonance imaging (MRI).

Cardiac imaging may be considered medically necessary if the results will affect individual management decisions. If a decision to perform cardiac catheterization or other angiography has already been made, imaging stress testing is considered not medically necessary.

A current clinical evaluation (within 60 days) is required prior to considering advanced imaging, which includes ALL of the following:

·         Relevant history and physical examination and appropriate laboratory studies, non-advanced imaging modalities, such as recent ECG (within 60 days), chest x-ray or ECHO/ultrasound, after symptoms started or worsened; and

o    Effort should be made to obtain copies of reported abnormal ECG studies in order to determine whether the ECG is uninterpretable; and

o    Most recent previous stress testing and its findings; and

o    Other meaningful contact (telephone call, electronic mail or messaging) by an established patient can substitute for a face-to-face clinical evaluation; and

·         Vital signs, height and weight or body mass index (BMI) or description of general habitus is needed; and

·         Advanced imaging should answer a clinical question which will affect management of the individuals clinical condition; and

·         Assessment of coronary artery disease may be considered medically necessary by the following:

o    Typical angina (definite):

§  Substernal chest discomfort (generally described as pressure, heaviness, burning, or tightness); or

§  Generally brought on by exertion or emotional stress and relieved by rest; or

§  May radiate to the left arm or jaw; or

§  When clinical information is received indicating that the individual is experiencing chest pain that is exertional or due to emotional stress, this meets the typical angina definition under the Pre-Test Probability Grid. No further description of the chest pain is required (location within the chest is not required); or

§  The Pre-Test Probability Grid (Table 1) is based on age, gender, and symptoms. All factors must be considered in order to approve for stress testing with imaging using the Pre-Test Probability Grid; or

o    Atypical angina (probable): Chest pain or discomfort (arm or jaw pain) that lacks one of the characteristics of definite or typical angina; or

o    Non-angina chest pain: Chest pain or discomfort that meets one or none of the typical angina characteristics; or

o    Angina variants or equivalents: a manifestation of myocardial ischemia which is perceived by the individual to be (otherwise unexplained) dyspnea, unusual fatigue, more often seen in women and may be unassociated with chest pain.

Stress Testing without Imaging

The Exercise Treadmill Test (ETT) without imaging may be considered medically necessary to include the following components of an ETT:

·         ECG that can be interpreted for ischemia; and

·         Individual capable of exercise on a treadmill or similar device (generally at 4 metabolic equivalents of task (METs) or greater; see functional capacity below).

An abnormal ETT (exercise treadmill test) includes ANY ONE of the following:

·         ST segment depression (usually described as horizontal or downsloping, greater or equal to 1.0 mm below baseline); or

·         Development of chest pain; or

·         Significant arrhythmia (especially ventricular arrhythmia); or

·         Hypotension

Functional capacity greater than or equal to 4 METs equates to the following:

·         Can walk four blocks without stopping; and

·         Can walk up a hill; and

·         Can climb one flights of stairs without stopping; and

·         Can perform heavy work around the house

Stress testing without imaging for any other indication not listed above is considered not medically necessary.  

Imaging Stress Tests include ANY ONE of the following:

·         Stress Echocardiography (Stress Echo); or

·         Myocardial Perfusion Imaging (MPI); or

·         Stress perfusion MRI

Stress testing with imaging can be performed with maximal exercise or chemical stress (dipyridamole, dobutamine, adenosine, or regadenoson).

Stress Testing with Imaging:

Stress echo, MPI or stress MRI, may be considered medically necessary for the following indications:

·         New, recurrent or worsening cardiac symptoms; AND with ANY of the following:

o    High pretest probability (greater than 90% probability of CAD) per Table 1; or

o    A history of CAD based on:

§  A prior anatomic evaluation of the coronaries; or

§  A history of CABG or PCI; or

o    Evidence or high suspicion of ventricular tachycardia; or

o    Age 40 years or greater and known diabetes mellitus; or

o    Coronary calcium score greater than or equal to 100; or

o    Poorly controlled hypertension defined as systolic BP greater than or equal to 180mmhg, if provider feels strongly that CAD needs evaluation prior to BP being controlled; or

o    ECG is uninterpretable for ischemia due to ANY ONE of the following:

§  Complete Left Bundle Branch Block (bifasicular block involving right bundle branch and left anterior hemiblock does not render ECG uninterpretable for ischemia); or

§  Ventricular paced rhythm; or

§  Pre-excitation pattern such as Wolff-Parkinson-White; or

§  Greater or equal to 1.0 mm ST segment depression ( Not nonspecific ST/T wave changes); or

§  LVH with repolarization abnormalities, also called LVH with strain (Not without repolarization abnormalities or by voltage criteria); or

§  T wave inversion in the inferior and/or lateral leads. This includes leads II, AVF, V5 or V6. (T wave inversion isolated in lead III or T wave inversion in lead V1 and V2 are not included); or

§  Individual on digitalis preparation; or

o    Continuing symptoms in an individual who had a normal or submaximal exercise treadmill test and there is suspicion of a false negative result; or

o    Individuals with recent equivocal, borderline, or abnormal stress testing where ischemia remains a concern; or

o    Heart rate less than 50 bpm in individuals on a beta blocker and/or calcium channel blocker medication where it is felt that the individual may not achieve an adequate workload for a diagnostic exercise study; or

o    Inadequate ET; or

§  Physical inability to achieve target heart rate (85% MPHR or 220-age.Target heart rate is calculated as 85% of the maximum age predicted heart rate (MPHR). MPHR is estimated as 220 minus the individuals age; or

§  History of false positive exercise treadmill test: a false positive ETT is one that is abnormal however the abnormality does not appear to be due to macrovascular CAD; or

·         Within 3 months of an acute coronary syndrome (e.g. ST segment elevation MI [STEMI], unstable angina, non-ST segment elevation MI [NSTEMI]), ONE MPI may be considered medically necessary to evaluate for inducible ischemia if ALL of the following related to the most recent acute coronary event applies:

o    Individual is hemodynamically stable; and

o    No recurrent chest pain symptoms and no signs of heart failure; and

o    No prior coronary angiography or imaging stress test in regards to the current episode of symptoms; or

·         Assessing myocardial viability in individuals  with significant ischemic ventricular dysfunction (suspected hibernating myocardium) and persistent symptoms or heart failure such that revascularization may be considered medically necessary for the following    indications:

o    Note: MRI, cardiac PET, MPI, or Dobutamine stress echo may be used to assess myocardial viability depending on physician preference; or

o    PET and MPI perfusion studies are usually accompanied by PET metabolic examinations.  Tl-201 MPI perfusion studies may assess viability without accompanying PET metabolism information; or

o    Unheralded syncope (not near syncope); or

o    Asymptomatic individual  with an uninterpretable ECG that:

§  Has never been evaluated; or

§  Is a new uninterpretable change; or

o    Individual with an elevated cardiac troponin; or

o    One routine study 2 years or more after a stent; or

§  Except with a left main stent where it can be done at 1 year; or

o    One routine study at 5 years or more after CABG, without cardiac symptoms; or

o    Every 2 years if there was documentation of previous “silent ischemia” on the imaging portion of a stress test but not on the ECG portion; or

o    To assess for CAD prior to starting a Class IC antiarrhythmic agent (flecainide or propafenone) and annually while taking the medication; or

o    Prior anatomic imaging study (coronary angiogram or CCTA) demonstrating coronary stenosis in a major coronary branch, which is of uncertain functional significance, can have one stress test with imaging; or

·         Evaluating new, recurrent, or worsening left ventricular dysfunction/CHF; please refer to Medical Policy X-181, Congestive Heart Failure for CHF; Imaging.

Stress echocardiography (Stress Echo), myocardial perfusion Imaging (MPI) or stress perfusion MRI for any other indication not listed above is considered not medically necessary. 

Preoperative Stress Testing with Imaging:

There are 2 steps that determine the need for imaging stress testing in (stable) preoperative

Individuals:

·         Would the individual qualify for imaging stress testing independent of planned surgery?

o    If yes, proceed to stress testing guidelines;

o    If no, go to Table 2.

·         Is the surgery considered high, moderate or low risk? (see Table 2).If high or moderate-risk, proceed below. If low-risk, there is no evidence to determine a need for preoperative cardiac testing.

o    High Risk Surgery: All individuals in this category should receive an imaging stress test if there has not been an imaging stress test within 1 year, unless the individual has developed new cardiac symptoms or a new change in the EKG since the last stress test.

o    Intermediate Surgery: One or more risk factors and unable to perform an ETT per guidelines if there has not been an imaging stress test within 1 year unless the individual has developed new cardiac symptoms or a new change in the EKG since the last stress test.

o    Low Risk: Preoperative imaging stress testing is considered not medically necessary.

·         Clinical Risk Factors (for cardiac death and non-fatal MI at time of non-cardiac surgery) may be considered medically necessary as follows:

o    Planned high risk surgery (open surgery on the aorta or open peripheral vascular surgery); or History of ischemic heart disease (previous MI, previous positive stress test, use of nitroglycerin, typical angina, ECG Q waves, previous PCI or CABG History of compensated previous congestive heart failure (history of heart failure, previous pulmonary edema, third heart sound, bilateral rales, chest xray showing heart failure); or

o    History of previous TIA or stroke; or

o    Diabetes Mellitus; or

o    Creatinine level greater than 2 mg/dL

Preoperative stress testing with imaging for any other indication not listed above is considered not medically necessary.  

Transplant:

Stress testing in individuals for non-cardiac transplant may be considered medically necessary for non-cardiac transplant for the following indications:

·         Individuals who are candidates for any type of organ bone marrow or stem cell Transplant can undergo imaging stress testing every year (usually stress echo or MPI) prior to transplant; or

·         Individuals who have undergone organ transplant are at increased risk for ischemic heart disease secondary to their medication. Risk of vasculopathy is 7% at one year, 32% at five years and 53% at ten years. An imaging stress test can be repeated annually after transplant for at least two years or within one year of a prior cardiac imaging study if there is evidence of progressive vasculopathy; or

·         After two consecutive normal imaging stress tests, repeated testing is not supported more often than every other year without evidence for progressive vasculopathy or new symptoms; or

·         Stress testing after five years may proceed according to normal patterns of consideration.

Post-Cardiac transplant assessment of transplant CAD may be considered medically necessary to be performed annually with one of the following imaging studies:

·         MPI; or

·         Stress ECHO; or

·         Stress MRI;; or

·         Cardiac PET perfusion with coronary flow quantitation

Stress testing in individuals for non-cardiac or post cardiac transplant for any other indication not listed above is considered not medically necessary.  

Non-imaging heart function and cardiac shunt imaging:

·         Echocardiogram may be considered medically necessary for cardiac shunt detection.

·         Ejection fraction may be considered medically necessary by echocardiogram, MPI, MUGA study, cardiac MRI, cardiac CT, or cardiac PET depending on the clinical situation rather than by non-imaging heart function study.

·         Cardiac shunt imaging study and non-imaging heart function study (measurement of central cardiovascular hemodynamics such as left ventricular ejection fraction performed noninvasively using scintillation probe) is considered not medically necessary.