Non-Invasive Vascular Studies

Language quoted from Centers for Medicare and Medicaid Services (CMS). National Coverage Determinations (NCDs) and coverage provisions in interpretive manuals is italicized throughout the policy. NCDs and coverage provisions in interpretive manuals are not subject to the Local Coverage Determination (LCD) Review Process (42 CFR 405.860[b] and 42 CFR 426 [Subpart D]). In addition, an administrative law judge may not review an NCD. See Section 1869(f)(1)(A)(i) of the Social Security Act.

Unless otherwise specified, italicized text represents quotation from one or more of the following CMS sources:

Title XVIII of the Social Security Act (SSA):

Section 1862(a)(1)(A) excludes expenses incurred for items or services which are not reasonable and necessary for the diagnosis or treatment of illness or injury or to improve the functioning of a malformed body member.

Section 1833(e) prohibits Medicare payment for any claim which lacks the necessary information to process the claim.

Code of Federal Regulations:

42 CFR, Section 410.32, indicates that diagnostic tests may only be ordered by the treating physician (or other treating practitioner acting within the scope of his or her license and Medicare requirements).

42 CFR, Section 410.33 provides guidelines for independent diagnostic testing facilities (IDTFs) including requirements for technician personnel and supervising physicians.

CMS Publications:

CMS Publication 100-02, Medicare Benefit Policy Manual, Chapter 11:

20.1 Noninvasive Vascular Studies for End Stage Renal Disease

(ESRD) Patients

CMS Publication 100-03, Medicare National Coverage Determinations Manual, Chapter 1:

20.14 Plethysmography

20.17 Noninvasive Tests of Carotid Function

220.5 Ultrasound Diagnostic Procedures

220.21 Thermography

CMS Publication 100-08, Medicare Program Integrity Manual, Chapter 13:

13.5 Content of an LCD

13.5.1 Reasonable and Necessary Provisions in LCDs

Abstract:

Non-invasive vascular studies utilize ultrasonic Doppler and physiologic principles to assess irregularities in blood flow in arterial and venous systems. The display may be a two dimensional image with spectral analysis and color flow or a plethysmographic recording. For the purposes of this policy, non-invasive vascular studies include duplex scans, physiologic studies and plethysmography.

Definitions:

Duplex scan: An ultrasonic scanning procedure with display of both two-dimensional structure and motion with time and Doppler ultrasonic signal documentation with spectrum analysis and/or color flow velocity mapping or imaging.

Physiologic studies: Functional measurement procedures that include Doppler ultrasound studies, blood pressure measurements, transcutaneous oxygen tension measurement, or plethysmography.

Plethysmography: Plethysmography involves the measurement and recording (by one of several methods) of changes in the size of a body part as modified by the circulation of blood in that part. Plethysmography is of value as a noninvasive technique for diagnostic, preoperative and postoperative evaluation of peripheral artery disease in the internal medicine or vascular surgery practice. It is also a useful tool for the preoperative podiatric evaluation of the diabetic patient or one who has intermittent claudication or other signs or symptoms indicative of peripheral vascular disease which have a bearing on the patient’s candidacy for foot surgery. (CMS Publication 100-03, Medicare National Coverage Decisions Manual, Chapter 1, Section 20.14)

Transcranial Doppler: Pulsed Doppler ultrasound is used to interrogate the intracranial vasculature of the Circle of Willis. Its value has been established in detecting severe stenosis in the major intracranial arteries, assessing patterns and extent of collateral circulation in patients with known regions of severe stenosis or occlusion and evaluating and following patients with vasoconstriction particularly after subarachnoid hemorrhage.

This local coverage determination specifies CGS policy for non-invasive vascular study testing.

INDICATIONS AND LIMITATIONS:

General Indications:

Non-invasive vascular studies are considered medically necessary if the ordering physician has reasonable expectation that their outcomes will potentially impact the clinical management of the patient. Services are deemed medically necessary when the following conditions are met:

• Significant signs/symptoms of arterial or venous disease are present;
• The information is necessary for appropriate medical and/or surgical management; and/or
• The test is not redundant of other diagnostic procedures that must be performed.

In general, non-invasive studies of the arterial system are utilized when invasive correction is contemplated. It is the responsibility of the physician/provider to ensure the medical necessity of procedures and documentation of such in the medical record.

Credentialing and Accreditation Standards

The accuracy of non-invasive vascular diagnostic studies depends on the knowledge, skill, and experience of the technologist and interpreter. Consequently, the physician performing and/or interpreting the study must be capable of demonstrating documented training and experience and maintain any applicable documentation. A vascular diagnostic study may be personally performed by a physician or a technologist.

The GAO Report to Congressional Committees entitled Medicare Ultrasound Procedures. Consideration of Payment Reforms and Technician Qualifications Requirements states that “Findings from several peer-reviewed studies, the Medicare Payment Advisory Commission, and ultrasound-related professional organizations support requiring that sonographers either have credentials or operate in facilities that are accredited, where specific quality standards apply. In some localities and practice settings, CMS or its contractors have required that sonographers either be credentialed or work in an accredited facility.” (GAO-07-734)

For areas under CGS Administrators, LLC jurisdiction the requirements will be effective for all providers 30 April 2011:

• All non-invasive vascular diagnostic studies must be performed under at least one of the following settings: (1) performed by a physician who is competent in diagnostic vascular studies or under the general supervision of physicians who have demonstrated minimum entry level competency by being credentialed in vascular technology, or (2) performed by a technician who is certified in vascular technology, or (3) performed in facilities with laboratories accredited in vascular technology.
  
  
• Examples of appropriate personnel certification include, but are not limited to the Registered Physician in Vascular Interpretation (RPVI), Registered Vascular Technologist (RVT), the Registered Cardiovascular Technologist (RCVT), Registered Vascular Specialist (RVS), and the American Registry of Radiologic Technologists (ARRT) credentials in vascular sonography. Appropriate laboratory accreditation includes the American College of Radiology (ACR) Vascular Ultrasound Program, and the Intersocietal Commission for the Accreditation of Vascular Laboratories (ICAVL).
  
  
• Additionally, transcutaneous oxygen tension measurements may be performed by individuals possessing the following credentials obtained from the National Board of Diving and Hyperbaric Medicine Technology (NBDHMT): Certified Hyperbaric Technologist (CHT), or Certified Hyperbaric Registered Nurse (CHRN).

Please Note: 42 CFR Section 410.33, Independent Diagnostic Testing Facilities, includes credentialing requirements that supersede those above:

The supervising physician must evidence proficiency in the performance and interpretation of each type of diagnostic procedure performed by the IDTF. The proficiency may be documented by certification in specific medical specialties or subspecialties or by criteria established by the carrier for the service area in which the IDTF is located. See 42 CFR Section 410-33 (2) (b).

Nonphysician personnel: Any nonphysician personnel used by the IDTF to perform tests must demonstrate the basic qualifications to perform the tests in question and have training and proficiency as evidenced by licensure or certification by the appropriate State health or education department. In the absence of a State licensing board, the technician must be certified by an appropriate national credentialing body. The IDTF must maintain documentation available for review that these requirements are met. See 42 CFR Section 410-33 (2)(c).

General Limitations:

A referral must be on record for each non-invasive study performed. A referral for one type of study does not qualify as a referral for all tests.

Non-invasive vascular studies are considered medically necessary only if the outcome will potentially impact the clinical course of the patient. For example, if a patient is (or is not) proceeding on to other diagnostic and/or therapeutic procedures regardless of the outcome of non-invasive studies, and non-invasive vascular procedures will not provide any unique diagnostic information that would impact patient management, then the non-invasive procedures are not medically necessary. If it is obvious from the findings of the history and physical examination that the patient is going to proceed to angiography, then non-invasive vascular studies are not medically necessary.

Non-invasive vascular studies include patient care required to perform the studies, supervision of the studies, and interpretation of study results with hard copy output or imaging. Digital storage of imaging is acceptable.

The use of any Doppler device that produces a record that does not permit analysis of bidirectional vascular flow or that does not provide a hard copy printout is part of the physical exam of the vascular system and is not reported separately. ( CPT Expert, 2004, 4th Edition)

The performance of simultaneous arterial and venous studies during the same encounter should be rare. Documentation should be available to support the medical necessity for both studies.

It is rarely necessary to perform cerebrovascular and upper extremity studies on the same day. Documentation supporting the need for both studies should be available for review.

Medicare does not pay for routine screening tests. ICD-10-CM diagnosis code Z13.9 (Special screening of other conditions, unspecified condition) should be used to indicate screening tests performed in the absence of a specific sign, symptom, or complaint. Use of ICD-10-CM code Z13.9 will result in the denial of claims as non-covered screening services.

I. Cerebrovascular Arterial Studies

Extracranial Arterial Studies (93880 - 93882)

Covered cerebrovascular arterial study testing methods include (real-time) duplex scans; and Doppler ultrasound waveform with spectral analysis.

Non-covered/non-reimbursed methods include testing methods that have not been found to be useful based on authoritative technological assessments or that are included as part of the physical examination.

Indications:

Cerebrovascular arterial studies may be considered medically necessary if one or more of the following signs and symptoms are present:

• Asymptomatic or symptomatic cervical bruits;
• Amaurosis fugax;
• Focal cerebral or ocular transient ischemic attacks (including but not limited to):
  
  • localizing symptoms, e.g., sensory loss; and/or
  • weakness of one side of the face; and/or
  • slurred speech; and/or
  • weakness of a limb;
• Syncope that is strongly suggestive of vertebrobasilar or bilateral carotid artery disease in etiology, as suggested by medical history;
• Recent history of a previous neurologic or cerebrovascular event;
• Before major cardiac and vascular surgery when a bruit is noted or there is a history of previous neurologic or cerebrovascular event;
• After carotid endarterectomy (outside the global period), or follow-up of previously documented stenoses;
• Pulsatile neck mass;
• Evaluation of blunt or penetrating neck trauma;
• Ocular microembolism (optic nerve/retinal arterial-Hollenhorst plaques/ocular);

Limitations: Studies may not be considered medically necessary if performed for the following signs and symptoms:

• Drop attack or syncope are rare indications usually seen with vertebrobasilar or bilateral carotid artery disease.
• Dizziness is not a typical indication unless associated with other localizing signs or symptoms. However, episodic dizziness with symptom characteristics typical of transient ischemic attacks may indicate medical necessity, especially when other more common sources, e.g., postural hypotension or transiently decreased cardiac output as demonstrated by cardiac event monitoring, have been previously excluded; and/or
• Headaches (including migraines).

Transcranial Doppler (TCD) Studies (93886 – 93893)

Transcranial Doppler (TCD) studies of the intracranial arteries and transcranial duplex imaging of extracranial arteries are approved methods of testing. The presence, location, and extent of disease can be evaluated by utilizing directional pulsed Doppler to estimate flow velocities and assess intracranial vessel hemodynamics and physiology.

Indications:

TCD studies are allowed for the following:

• Detection and evaluation of the hemodynamic effects of severe stenosis or occlusion of the extracranial (greater than or equal to 60% diameter reduction) and major basal intracranial arteries (greater than or equal to 50% diameter reduction);
• Detection and serial evaluation of cerebral vasospasm complicating subarachnoid hemorrhage;
• Evaluation of intracranial hemodynamic abnormalities in patients with suspected brain death;
• Intraoperative and perioperative monitoring of intracranial flow velocity and hemodynamic patterns during carotid endarterectomy, (although the professional component could only be reimbursed if it is provided during the operative procedure by a physician that is not a member of the operating team);
• Evaluation of cerebral embolization; and/or
• Assessing hemodynamic effects, patterns, and extent of collateral circulation in patients with known regions of severe stenosis or occlusion when necessary to care for the patient; and
• Assessing stroke risk in children aged two to sixteen with homozygous sickle cell disease; and
• As an alternative to an echocardiogram to detect residual right to left shunting after repair/closure of an intracardiac or intrapulmonary shunt.

Multiple cerebrovascular procedures may be allowed during the same encounter given the physician/provider can demonstrate medical necessity as documented in the patient’s medical record. For example, physiologic studies and a duplex scan are allowed on the same date of service given the provider is able to document medical necessity, e.g., greater than or equal to 50% stenosis on duplex scan or significant symptoms as demonstrated by the indications for the study.

Limitations:

TCD studies are not indicated for:

• Evaluation of brain tumors;
• Assessment of familial and degenerative disease of the cerebrum, brainstem, cerebellum, basal ganglia and motor neurons;
• Evaluation of infectious and inflammatory conditions;
• Psychiatric disorders; and/or
• Epilepsy.

Transcranial Doppler (TCD) is considered investigational and not medically necessary for the following indications:

• Assessing patients with migraine;
• Monitoring during cardiopulmonary bypass and other cerebrovascular and cardiovascular interventions, and surgical procedures (except during carotid endarterectomy, as noted above);
• Evaluation of patients with dilated vasculopathies such as fusiform aneurysms;
• Assessing autoregulation, physiologic, and pharmacological responses of cerebral arteries; and/or
• Evaluating children with various vasculopathies, such as moyamoya disease and neurofibromatosis.

II. Peripheral Arterial Examinations (93922 - 93931)

Covered peripheral arterial study testing methods include duplex scans; Doppler waveform or spectral analysis; volume, impedance or strain gauge plethysmography; and transcutaneous oxygen tension measurement.

Non-covered peripheral arterial study testing methods include thermography, mechanical oscillometry, inductance or capacitance plethysmography, photoelectric plethysmography, differential plethysmography, and light reflective rheography.

Indications:

Non-invasive peripheral arterial examinations, performed to establish the level and/or degree of arterial occlusive disease, are medically necessary if (1) significant signs and/or symptoms of possible limb ischemia are present and (2) the patient is a candidate for invasive/surgical therapeutic interventions. Acute ischemia is characterized by the sudden onset of severe pain, coldness, numbness and pallor of the extremity. Chronic ischemia can be manifested by intermittent claudication, pain at rest, diminished pulse, ulceration, and gangrene.

A routine history and physical examination, which includes ankle/brachial indices (ABIs), can readily document the presence or absence of ischemic disease in the majority of cases. It is not medically necessary to proceed beyond the physical examination for minor signs and symptoms such as hair loss, absence of a single pulse, relative coolness of a foot, shiny thin skin, or lack of toe nail growth unless related signs and/or symptoms are present which are severe enough to require possible invasive intervention.

An ABI is not a reimbursable procedure by itself; rather, ABI may be reimbursed when derived from a more comprehensive procedure which includes a permanent chart copy of the measured pressures and waveforms in the examined vessels. An ABI should be abnormal, e.g., and must be accompanied by another appropriate indication before proceeding to more sophisticated or complete studies, except in patients with severe diabetes or uremia resulting in medial calcification as demonstrated by artifactually elevated ankle blood pressure.

Peripheral artery studies may be considered medically necessary if the following signs and symptoms are present:

• Claudication of such severity that it interferes significantly with the patient’s occupation or lifestyle, or claudication with inability to stress the patient;
• Rest pain (typically including the forefoot), usually associated with absent pulses, which becomes increasingly severe with elevation and diminishes with placement of the leg in a dependent position;
• Tissue loss defined as gangrene or pre-gangrenous changes of the extremity, or ischemic ulceration of the extremity occurring in the absence of pulses;
• Aneurysmal disease;
• Evidence of thromboembolic events;
• Blunt or penetrating trauma (including complications of diagnostic and/or therapeutic procedures); and/or
• Follow-up of grafts or other vascular intervention

Pre-surgical conduit assessment of the upper extremity/radial artery(ies) may be performed prior to use in coronary artery bypass grafting (CABG) or as other arterial conduits.

Limitations:

Peripheral artery studies may not be considered medically necessary if only the following signs and symptoms are present:

• Continuous burning of the feet (considered to be a neurologic symptom);
• Leg pain, nonspecific (M79.606) and pain in limb (M79.669) as single diagnoses are too general to warrant further investigation unless they can be related to other signs and symptoms;
• Edema rarely occurs with arterial occlusive disease unless it is in the immediate postoperative period, in association with another inflammatory process or in association with rest pain; and/or
• Absence of pulses in minor arteries, e.g., dorsalis pedis or posterior tibial, in the absence of symptoms. The absence of pulses is not an indication to proceed beyond the physical examination unless it is related to other signs and/or symptoms.

Duplex scanning and physiologic studies may be reimbursed during the same encounter if the physiologic studies are abnormal and/or to evaluate vascular trauma, thromboembolic events or aneurysmal disease, if the physician/provider can document medical necessity in the patient’s medical record.

In general, non-invasive studies of the arterial system are to be utilized when invasive correction is contemplated or severity of findings dictate non-invasive study follow-up, but not for following non-invasive medical treatment regimens. The latter may be followed with physical findings and/or progression or relief of signs and/or symptoms. Screening of the asymptomatic patient is not covered by Medicare.

III. Peripheral Venous Examinations (93970-93971)

Indications for venous examinations are separated into three major categories: deep vein thrombosis (DVT), chronic venous insufficiency, and vein mapping. Studies are medically necessary only if the patient is a candidate for anticoagulation, thrombolysis or invasive therapeutic procedure(s).

Since the signs and symptoms of arterial occlusive disease and venous disease are so divergent, the performance of simultaneous arterial and venous studies during the same encounter should be rare. Consequently, documentation clearly supporting the medical necessity of both procedures performed during the same encounter must be available in the patient’s medical record.

Deep Vein Thrombosis (DVT)

The signs and/or symptoms of DVT are relatively non-specific; and due to the risk associated with pulmonary embolism (PE), objective testing is allowed in patients who are candidates for anticoagulation or invasive therapeutic procedures for the following:

• Clinical signs and/or symptoms of DVT including, but not limited to, edema, tenderness, inflammation, and/or erythema;
• Clinical signs and/or symptoms of pulmonary embolus (PE) including, but not limited to, hemoptysis, chest pain, and/or dyspnea;
• Unexplained lower extremity edema status, post major surgical procedures, trauma, other or progessive illness/condition; and/or
• Unexplained lower extremity pain, excluding pain of skeletal origin.

These studies are rarely considered medically necessary for the following:

• Bilateral limb edema in the presence of signs and/or symptoms of congestive heart failure, exogenous obesity and/or arthritis; and/or
• Follow-up of phlebitis unless signs/symptoms suggest possible extension of thrombus.

Chronic Venous Insufficiency

Chronic venous insufficiency may be divided into three categories: primary varicose veins, recurrent DVT, and post-thrombotic (post-phlebitic) syndrome. Peripheral venous studies may be indicated for the evaluation of:

• Venous function in patients with ulceration suspected to be secondary to venous insufficiency when documenting venous valvular incompetence prior to invasive therapeutic intervention;
• Varicose veins by themselves do not indicate medical necessity, but medical necessity may be indicated when they are accompanied by significant pain or stasis dermatitis; and/or
• Superficial thrombophlebitis involving the proximal thigh (to investigate whether there was thrombus at the saphenofemoral junction that would demand either anticoagulation or surgical ligation).

Vein Mapping

Mapping the saphenous veins prior to scheduled revascularization procedures is covered by Medicare when it is expected that an autologous vein will be used, but only if there is uncertainty regarding the availability of a suitable vein for by-pass.

Vein mapping is not always necessary as a routine pre-operative study but is medically reasonable when the patient’s clinical evaluation indicates one of the following:

• Previous partial harvest of the vein;
• Previous thrombophlebitis or DVT in the leg;
• Severe varicose veins;
• Previous history of vein stripping, ligation, or sclerotherapy;
• Obesity to the degree it interferes with clinical determination;

Other examples must clearly be supported by the medical documentation.

Vein mapping may be performed prior to creating a dialysis fistula. Please see “VI. Vessel Mapping of Vessels for Hemodialysis Access (93990/G0365).”

IV. Visceral Vascular Studies (93975, 93976, 93978, 93979)

Indications:

This procedure is indicated in the evaluation and/or management of vascular disease involving vessels of the abdominal, pelvic, scrotal contents, and/or retroperitoneal organs.

Limitations:

Duplex scanning in the evaluation of an abdominal aortic aneurysm is of limited value unless there is a pulsatile abdominal mass and signs and symptoms of peripheral vascular disease are present. Follow-up of an abdominal aneurysm on a periodic basis using abdominal ultrasound rather than visceral vascular studies to determine growth and potential need for intervention is allowed.

Vascular studies are not the initial diagnostic modality for the evaluation of abdominal pain/tenderness. There must be a high index of suspicion that the pain is caused by a vascular disorder, such as mesentery ischemia.

Noninvasive vascular studies are medically necessary only if the outcome will potentially impact the clinical course of the patient. For example, if a patient is going to proceed on to other diagnostic and/or therapeutic procedures regardless of the outcome of noninvasive studies, noninvasive vascular procedures are usually not medically necessary. That is, if it is obvious from the findings of the history and physical examination that the patient is going to proceed to angiography, then noninvasive vascular studies may not be medically necessary.

V. Hemodialysis Access Examination (93990)

Indications:

Medicare will consider separate payment for vascular studies (CPT code 93990) on symptomatic ESRD patients, when Doppler flow studies are used to provide diagnostic information to determine the appropriate medical intervention. Medicare considers a Doppler flow study medically necessary when the beneficiary’s dialysis access site manifests signs or symptoms associated with vascular compromise, and when the results of this test are necessary to determine the clinical course of treatment.

Signs or symptoms in patients with ESRD of impending failure of the hemodialysis access site, including:

• Elevated venous pressure > 200mm Hg on a 200 cc/min. pump;
• Elevated recirculation of time of 12% or greater, and
• Low urea reduction rate < 60%
• An access with a palpable "water hammer" pulse on examination (which implies venous outflow obstruction)

VI. Vessel Mapping of Vessels for Hemodialysis Access (93990/G0365)

Indications:

Vessel mapping of vessels for hemodialysis access is considered for Medicare payment when it is performed preoperatively prior to creation of hemodialysis access using an autogenous hemodialysis conduit, including arterial inflow and venous outflow.

Limitations:
Medicare will limit payment to either a Doppler flow study (93990/G0365) or an angiogram (fistulogram, venogram, 75790 with 36145 or 75820 with 36005), but not both, unless documentation is provided to support the medical necessity for both studies.

An example of a clinical situation demonstrating the need for both studies would be a scenario where a Doppler flow study demonstrates reduced flow (blood flow rate less than 800 cc/min or a decreased flow of 25% or greater from previous study), and the physician requires an arteriogram, to define the extent of the problem. The patient's medical record(s) must provide documentation supporting the need for more than one imaging study.

If the service is done for monitoring purposes, it is not covered under Part B. No separate payment for non-invasive vascular studies for monitoring the access site of an ESRD patient, whether coded as the access site or peripheral site, is permitted to any entity.

The technical component of HCPCS code G0365 and CPT code 93990 (modifier TC) performed in End-State Renal Disease (ESRD) facilities or for ESRD patients is included in the composite payment rate. This rate is a comprehensive payment that includes all services, equipment, supplies and certain laboratory tests and drugs that are necessary for dialysis treatment.

The professional component for the procedure (modifier 26) is included in the monthly capitation payment (MCP) if billed by the MCP physician. Physicians other than the MCP provider (or a member of his/her group of the same specialty) may bill separately for interpretations of tests.

Services performed on ESRD patients by entities outside the ESRD facility must bill the ESRD facility for payment of monitoring procedures.

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CGS and other Medicare contractors’ local coverage determinations.

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References added to support reconsideration request - 01/01/2010

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