LCD L38396: Cardiology Non-emergent Outpatient Stress Testing

Compliance with the provisions in this LCD may be monitored and addressed through post payment data analysis and subsequent medical review audits.

History/Background and/or General Information

Noninvasive testing in the outpatient setting to assess for coronary artery disease (CAD) and left ventricular (LV) dysfunction may be accomplished by utilizing conventional exercise stress testing without imaging or by utilizing exercise or pharmacologic stress testing with imaging.

Cardiovascular stress testing, also referred to as exercise stress test (EST), exercise electrocardiogram, exercise treadmill test (ETT), graded exercise test, or stress electrocardiogram (ECG), is used to provide information about how the heart responds to exertion.

Types of stress testing with imaging addressed in this LCD include stress echocardiography, single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI), positron emission tomography (PET) MPI, and cardiac magnetic resonance imaging (CMR). Stress testing with imaging can be performed with maximal exercise or chemical stress (dipyridamole, dobutamine, adenosine, regadenoson, or other provocative agents). 1,2

Stress echocardiography, SPECT MPI, PET MPI and CMR are considered equivalent diagnostic tests. However, in addition to myocardial ischemia, stress echocardiography can provide information that is not obtainable with MPI, such as valve function, assessment of pulmonary pressure, and assessment of dynamic obstruction. The most commonly performed myocardial perfusion imaging are single (at rest or stress) and multiple (at rest and stress) SPECT studies. The CMR can also distinguish scar from hibernating myocardium, provide information about valvular function, the presence of myocardial fibrosis, the presence of morphological abnormalities, and provide an assessment of dynamic obstruction without radiation exposure. This is especially valuable in patients in whom good quality echocardiography images could not be obtained due to technically difficult acoustic windows. 3,4

In many instances, EST may be combined with imaging procedures, such as MPI, echocardiography, or other imaging procedures.

A pharmacologic stress test may be performed when patients are unable to exercise. This test involves the administration of a medication that is designed to make the heart respond as if the patient was exercising. The pharmacologic testing allows the provider to determine how the heart responds to stress in the absence of exercise.

Imaging of myocardial perfusion can also be combined with myocardial metabolism imaging with fluorodeoxyglucose (F-18 FDG) for the assessment of myocardial viability in areas of resting hypoperfusion and dysfunctional myocardium. The stress protocols are, for the most part, similar for all cardiac PET perfusion agents. The specific differences in acquisition protocols for rubidium (Rb-82) and ammonia N-13 are related to the duration of uptake and clearance of these radiopharmaceuticals and their physical half-lives.

Covered Indications

Stress testing without cardiac imaging will be considered medically reasonable and necessary for:

• Patients with low or intermediate pre-test probability for CAD who are exhibiting cardiac symptoms, including otherwise unexplained angina equivalent symptoms with normal or minor changes in resting ECG and no contraindications to exercise. 5-10

• Patients with diabetes mellitus who are exhibiting cardiac symptoms, including otherwise unexplained angina equivalent symptoms, with normal or minor changes in resting ECG and no contraindications to exercise. 11

• New-onset atrial fibrillation (with no prior cardiac evaluation). 10,12,13

• Determining functional capacity and response to therapy in patients with hypertrophic cardiomyopathy (HCM). 14

• Patients with an intermediate or high CHD risk (ATP III risk criteria) who have experienced syncope (an abrupt, transient, complete loss of consciousness) and cardiac etiology is suspected based on an initial evaluation, including history, physical examination, or ECG and the patient is able to exercise. 6,8,10,15,16

• Patients without cardiac symptoms who underwent a percutaneous coronary intervention (PCI) (with a stent) procedure more than 2 years prior or a coronary artery bypass graft (CABG) more than 5 years prior and have not undergone an evaluation for CAD within the past 2 years (stress echocardiogram, SPECT MPI, PET MPI, CMR, coronary computed tomography angiography [CCTA], cardiac catheterization) and are able to exercise. 6,7,8,15,17,18

• Patients with established CAD who experienced an acute coronary syndrome (ACS) event (ST segment elevation myocardial infarction [STEMI], a Non–ST segment elevation myocardial infarction [NSTEMI], or unstable angina) within the past 90 days provided that they did not undergo coronary angiography at the time of the acute event and are currently clinically stable and able to exercise. 6,8

• Patients with disease conditions associated with CAD (e.g., atherosclerotic abdominal aortic aneurysm, peripheral vascular disease, carotid artery disease, chronic renal failure) with no stress testing evaluation performed within the preceding 2 years and who are able to exercise. 5,7,10,17

• Pre-operative cardiac evaluation in patients able to exercise and who will be undergoing noncardiac surgery with one of the following 19 :

• Intermediate risk for surgery (cardiac risk 1-5%), unknown functional capacity, and the results will affect patient management decisions.

• High risk for surgery (> 5% cardiac risk), unknown functional capacity, and the results will affect patient management decisions.

Stress testing with cardiac imaging will be considered medically reasonable and necessary for:

• Patients experiencing new, recurrent, or worsening cardiac symptoms, including otherwise unexplained angina equivalent symptoms, AND any of the following:

• Physical inability to perform a maximum exercise workload 2,5,6,8-10,15,20 ; OR

• New or previously unrecognized uninterpretable ECG 2,5,6,8-10 OR ;

• ECG is uninterpretable for ischemia due to any one of the following 2,5,8,9,15,21 :

• Complete left bundle branch block (right bundle branch does not render ECG uninterpretable for ischemia), 21

• Ventricular paced rhythm,

• Pre-excitation pattern such as Wolff-Parkinson-White,

• A > 1 mm ST segment depression (NOT nonspecific ST/T wave changes),

• Left ventricular hypertrophy (LVH) with repolarization abnormalities, also called LVH with strain (NOT without repolarization abnormalities or by voltage criteria), or

• Patient on digoxin therapy.

• A history of CAD based on a prior anatomic evaluation of the coronary arteries OR a history of CABG or PCI; 6,8,15 OR

• Syncope and collapse (an abrupt, transient, complete loss of consciousness) for patients with an intermediate or high CHD risk (ATP III risk criteria) and where cardiac etiology is suspected based on an initial evaluation, including history, physical examination, or ECG and patient is unable to exercise; 6,8,10,15,16 OR

• Evidence or high suspicion of ventricular arrhythmias: 6,7,8,10 OR

• Worsening or continuing symptoms in a patient who had a normal or submaximal exercise stress test and there is suspicion of a false negative result; 20,22 OR

• Patients with recent equivocal or borderline testing where ischemia remains a concern; 8,15,20 OR

• Patients on beta blocker, calcium channel blocker, and/or antiarrhythmic medication when the documentation supports that an adequate workload may not be attainable to enable a fully diagnostic exercise study; 2,5 OR

• History of false positive exercise stress test (e.g., one that is abnormal, but the abnormality does not appear to be due to macrovascular CAD); 8,22 OR

• Evaluation of chest pain syndrome after revascularization or in patients with intermediate to high pre-test probability for CAD regardless of ECG interpretability or ability to exercise; 7,8 OR

• High pre-test probability for CAD regardless of ECG interpretability or the ability to exercise, and a decision to perform cardiac catheterization or other angiography has not already been made; 7,8,10,15 OR

• Patients with HCM; 14 OR

• New-onset atrial fibrillation (with no prior cardiac evaluation). 10,12,13

• Patients with disease conditions associated with CAD (e.g., atherosclerotic abdominal aortic aneurysm, peripheral vascular disease, carotid artery disease, chronic renal failure) with no stress imaging evaluation performed within the preceding 2 years and are unable to exercise. 5,7,10,17

• Patients without clear cardiac symptoms in the presence of an elevated cardiac troponin. 6,8

• Patients without cardiac symptoms who underwent a PCI (with stent) procedure more than 2 years prior or a CABG more than 5 years prior and have not undergone an evaluation for CAD within the past 2 years (stress echocardiogram, SPECT MPI, PET MPI, CMR, coronary computed tomography angiography [CCTA], cardiac catheterization) and are unable to exercise. 6,7,8,15,17,18

• Patients with established CAD who experienced an ACS event (STEMI, NSTEMI, or unstable angina) within the past 90 days provided that they did not undergo coronary angiography at the time of the acute event and are currently clinically stable. 6,8

• Evaluating new, recurrent, or worsening left ventricular dysfunction/congestive heart failure. 6-8,10,23

• Assessing myocardial viability in patients with significant ischemic ventricular dysfunction (suspected hibernating myocardium) and persistent symptoms or heart failure such that revascularization would be considered. 6-9,15,23

• Pre-operative cardiac evaluation in patients not able to exercise and who will be undergoing noncardiac surgery with one of the following 6-8,15,17,19 :

• Intermediate risk for surgery (cardiac risk 1-5%), poor ( 5% cardiac risk), poor (

• Asymptomatic patients with a coronary calcium Agatston score >400. 6-8,17

• Planned cardiac or other solid-organ transplant when no cardiac evaluation has been performed within the past year. 10,24

• Patients who will be treated with interleukin 2 products for various malignant disorders. 25 The Food and Drug Administration (FDA) has issued a black box warning for interleukin 2 products. See the FDA drug label for the FDA black box warning: https://labels.fda.gov/

• Stress echocardiography for the evaluation of moderate to severe valvular heart disease, suspected pulmonary artery hypertension, and re-evaluation of exercise-induced pulmonary hypertension to evaluate response to therapy. 6,26

• Stress echocardiography for the detection and quantification of dynamic left ventricular outflow tract (LVOT) obstruction in the absence of resting LVOT in patients with HCM. 14

• CMR in patients with HCM when echocardiography is inconclusive or there are poor echocardiograph imaging windows. 4

• Evaluation of transplant coronary artery disease (TCAD) or cardiac allograft vasculopathy (CAV) in patients with a history of organ transplantation. 27-40

• Utilization of PET MPI in the determination of cardiac involvement using fluorodeoxyglucose (F-18 FDG) to diagnose cardiac sarcoidosis in patients who are unable to undergo MRI, have inconclusive MRI findings, or when high probability of disease exists even after a negative MRI. Examples of patients who are unable to undergo MRI include, but are not limited to, patients with metal implants. 15,41-48

• Utilization of PET MPI using fluorodeoxyglucose (F-18 FDG) to determine response to immunosuppressive therapy in patients diagnosed with cardiac sarcoidosis. 15,41-45,47,48

• Additional indications for PET Scans and SPECT are outlined in the CMS IOM Publication 100-03, Medicare National Coverage Determinations (NCD) Manual , Chapter 1, Part 4, Sections 220.6 Positron Emission Tomography (PET) Scans, 220.6.1 PET for Perfusion of the Heart, 220.6.8 FDG PET for Myocardial Viability, and 220.12 Single Photon Emission Computed Tomography (SPECT).

• Cardiovascular stress testing may be performed in conjunction with additional cardiac diagnostic tests including echocardiography and nuclear cardiac imaging. However, selection of the test should be made within the context of other testing modalities so that the expected information does not become redundant.

• Patients with recently demonstrated coronary stenosis of uncertain functional significance in a major coronary branch on an anatomic imaging study (coronary angiogram or CCTA) may have one stress test with imaging. 6-8,49

Limitations

The following are considered not medically reasonable and necessary:

• Screening for coronary artery disease in asymptomatic patients unless under specific conditions as outlined in this LCD. Please refer to CMS IOM Publication 100-02, Medicare Benefit Policy Manual , Chapter 16, Section 20 Services Not Reasonable and Necessary.

• Routine screening for CAD in asymptomatic patients with diabetes mellitus. 11

• Routine stress testing in asymptomatic patients with abnormal prior stress imaging. 6,8,10

• Routine stress testing in asymptomatic patients with obstructive or nonobstructive CAD without a revascularization procedure. 6,8,10

• Exercise testing or radiologic imaging within the first 2 years following PCI without specific symptoms (e.g., chest pain, ECG changes, etc.). 8,17,18

• Utilization of SPECT MPI, PET MPI, stress echocardiography, and CMR in patients with low pretest probability of CAD, interpretable ECG, and the ability to exercise. 6-9,49

• The routine and repetitive monitoring of patients beyond the first cardiac stress test, in the absence of a documented change in condition (e.g., new symptoms or progression of existing symptoms).

• Cardiovascular stress testing with or without cardiac imaging if the results will not affect patient management decisions. 49

• Cardiovascular stress testing with or without cardiac imaging when a decision to perform cardiac catheterization or other angiography has already been made. 49

• Stress testing with or without imaging for pre-operative evaluation for low risk noncardiac surgery. 6-8,19,49

• Stress testing with or without imaging for pre-operative evaluation of asymptomatic patients undergoing intermediate or high risk noncardiac surgery would not be expected for patients 12 months following a normal stress echocardiography, SPECT MPI, PET MPI, CMR, coronary computed tomography angiography (CCTA), or cardiac catheterization. 7,10,19

• Utilization of SPECT MPI, PET MPI, stress echocardiography or CMR for the pre-operative evaluation of planned intermediate or high risk, noncardiac surgery, in the patient with normal or minor changes in resting ECG would not be expected for patients with no contraindications to exercise. 6-8,17,19

• Absolute contraindications to exercise stress testing (not an all-inclusive list) 2,5 :

• Within 2 to 4 days of an acute myocardial infarction

• High-risk unstable angina

• Uncontrolled cardiac arrhythmias causing symptoms or hemodynamic compromise

• Symptomatic severe aortic stenosis

• Decompensated or uncontrolled congestive heart failure

• Systolic blood pressure (BP) at rest >200 mmHG or diastolic BP at rest >110 mmHg

• Acute pulmonary embolus or pulmonary infarction

• Acute myocarditis or pericarditis

• Acute aortic dissection

• Severe pulmonary hypertension

• Acute symptomatic medical illness

Multiple guidelines and appropriate use criteria are available for cardiovascular stress testing with and without cardiac imaging.

Pretest probability is used to determine if cardiovascular stress testing is appropriate and whether cardiac imaging is also appropriate. 5-10,15 The pretest probability of CAD is based on age, sex, and symptoms. 5

Evidence-based guidelines

Exercise stress testing without cardiac imaging