(Medicare National Coverage Determinations Manual)

Medicare coverage is extended to those procedures listed in Category I below when used for the accepted medical indications mentioned above.  The procedures in Category II are still considered experimental and are not covered at this time.  Denial  of claims because a noncovered procedure was used or because there was no medical indication for plethysmographic evaluation of any type should be based on 1862(a)(1)  of the Act.   Category I - Covered   Segmental Plethysmography -  Included under this procedure are services performed with a regional plethysmograph, differential plethysmograph, recording oscillometer, and a pulse volume recorder.   Electrical Impedance Plethy smography  Ultrasonic Measurement of Blood Flow (Doppler) -  While not strictly a plethysmographic method, this is also a useful tool in the evaluation of suspected peripheral vascular disease or preoperative screening of podiatric patients with suspected peripheral vascular compromise.  (See 220.5 for the applicable coverage policy on this procedure.)   Oculoplethysmography -  See 20.17, Noninvasive Tests of Carotid Function.   Strain Gauge Plethysmography -  This test is based on recording the non -pulsatile aspects of inflowing blood at various points on an extremity by a mercury -in-silastic strain gauge sensor.  The instrument  consists of a chart recorder, an automatic cuff inflation and deflation system, and a recording manometer.   Category II -  Experimental   The following methods have not yet reached a level of development such as to allow their routine use in the evaluation of suspected peripheral vascular disease.   Inductance Plethysmography -  This method is considered experimental and does not provide reproducible results.   Capacitance Plethysmography -  This method is considered experimental and does not provide reproducible results.   Mechanical Oscillometry -  This is a nonstandardized method which offers poor sensitivity and is not considered superior to the simple measurement of peripheral blood pressure.   Photoelectric Plethysmography -  This method is considere d useful only in determining whether or not a pulse is present and does not provide reproducible measurements of blood flow.  Differential plethysmography, on the other hand, is a system which uses an impedance technique to compare pulse pressures at various points along a limb, with a reference pressure at the mid -brachial or wrist level.  It is not clear whether this technique, as usually performed in the physicians office, meets the definition of plethysmography because quantitative measurements of bloo d flow are usually not made.  It has been concluded, in any event, that the differential plethysmography system is a blood pulse recorder of undetermined value which has the potential for significant overutilization.  Therefore, reimbursement for studies d one by techniques other than venous occlusive pneumoplethysmography should be denied, at least until additional data on these devices, including controlled clinical studies, become available.   20.15  Electrocardiographic Services  (Rev. 173, Issued: 09- 04-14, Effective: Upon Implementation: of ICD -10, Implementation: Upon Implementation of ICD - 10)  A. General   1. An electrocardiogram (EKG) is a graphic representation of electrical activity within the heart.  Electrodes placed on the body in predetermined locations sense this electrical activity, which is then recorded by various means for review and interpretation.  EKG recordings are used to diagnose a wide range of heart disease and other conditions that manifest themselves by abnormal cardiac electrical activity.   EKG services are covered diagnostic tests when there are documented signs and symptoms or other clinical indications for providing the service.  Coverage includes the review and interpret ation of EKGs only by a physician.  There is no coverage for EKG services when rendered as a screening test or as part of a routine examination unless performed as part of the one -time, Welcome to Medicare preventive physical examination under section 611 of the Medicare Prescription Drug, Improvement, and Modernization Act of 2003.  2. Ambulatory electrocardiography (AECG) refers to services rendered in an outpatient setting over a specified period of time, generally while a patient is engaged in daily a ctivities, including sleep. AECG devices are intended to provide the physician with documented episodes of arrhythmia, which may not be detected using a standard 12- lead EKG.  AECG is most typically used to evaluate symptoms that may correlate with intermittent cardiac arrhythmias and/or myocardial ischemia.  Such symptoms include syncope, dizziness, chest pain, palpitations, or shortness of breath.  Additionally, AECG is used to evaluate patient response to initiation, revision, or discontinuation of arrhy thmic drug therapy.   3. The Centers for Medicare & Medicaid Services (CMS), through the national coverage determination (NCD) process, may create new ambulatory EKG monitoring device categories if published, peer -reviewed clinical studies demonstrate evidence of improved clinical utility, or equal utility with additional advantage to the patient, as indicated by improved patient management and/or improved health outcomes in the Medicare population (such as superior ability to detect serious or life -threaten ing arrhythmias) as compared to devices or services in the currently described categories below.  Descriptions of Ambulatory EKG Monitoring Technologies   1. Dynamic electrocardiography devices that continuously record a real -time EKG, commonly known as Hol ter monitors, typically record over a 24 -hour period.  The recording is captured either on a magnetic tape or other digital medium.  The data is then computer -analyzed at a later time, and a physician interprets the computer -generated report.  A 24- hour r ecording is generally adequate to detect most transient arrhythmias. Documentation of medical necessity is required for monitoring longer than 24 hours.  The recording device itself is not covered as durable medical equipment (DME) separate from the total diagnostic service.   2. An event monitor, or event recorder , is a patient -activated or event -activated EKG device that intermittently records cardiac arrhythmic events as they occur.  The EKG is recorded on magnetic tape or other digital medium.  Cardiac event monitor technology varies among different devices.  For patient -activated event monitors, the patient initiates recording when symptoms appear or when instructed to do so by a physician (e.g., following exercise).  For self -sensing, automatic ally triggered monitors, an EKG is automatically recorded when the device detects an arrhythmia, without patient intervention.  Some devices permit a patient to transmit EKG data transtelephonically (i.e., via telephone) to a receiving center where the dat a is reviewed.  A technician may be available at these centers to review transmitted data 24 hours per day.  In some instances, when the EKG is determined to be outside certain pre -set criteria by a technician or other non- physician, a physician is available 24 hours per day to review the transmitted data and to make clinical decisions regarding the patient.  These services are known as 24 -hour attended monitoring.  In other instances, transmitted EKG data is reviewed at a later time and are, therefore, considered non-attended.   Cardiac event monitors without transtelephonic capability must be removed from the patient and taken to a location for review of the stored EKG data.  Some devices also permit a "time sampling" mode of operation.  The "time sampling" mode is not covered under ambulatory EKG monitoring technology.  Some cardiac event monitoring devices with trans -telephonic capabilities require the patient to dial the phone number of a central EKG data reception center and initiate transmission of EKG data. Other devices use Internet -based in -home computers to capture and store EKG data.  When such devices detect pre -programmed arrhythmias, data is automatically sent via modem and standard telephone lines to a central receiving center, or independent diagnostic testing facility (IDTF), where the data is reviewed.  Internet -based in- home computer systems may also provide the receiving center with a daily computer -generated report that summarizes 24 hours of EKG data.   Certain cardiac event monitors capture electrical activity with a single electrode attached to the skin.  Other devices may employ multiple electrodes in order to record more complex EKG tracings.  Additionally, devices may be individually programmed to detect patient -specific factors, el ectrode malfunction, or other factors.  Cardiac event monitors can be further categorized as either pre- event or post -event recorders, based on their memory capabilities:  a. Pre-symptom Memory Loop Recorder (MLR)   Upon detecting symptoms, the wearer presses a button, which activates the recorder to save (i.e., memorize) an interval of pre -symptom EKG data along with data during and subsequent to the symptomatic event.  Self -sensing recorders (also known as event -activated or automatic trigger) do not r equire patient input to capture these data.  Single or multiple events may be recorded.  The device is worn at all times, usually for up to 30 days.  o Implantable (or Insertable Loop) Recorder (ILR)   Another type of pre -symptom MLR, it is implanted subcutaneously in a patients upper left chest and may remain implanted for many months.  An ILR is used when syncope is thought to be cardiac -related, but is too infrequent to be detected by either a Holter  monitor or a traditional pre -symptom MLR.  b. Post-symptom Recorder   The patient temporarily places this device against the chest when symptoms occur and activates it by pressing a button.  These recorders represent old technology, as they do not include a memory loop.  The device transmits EKG data telephonic ally in real -time and is usually used for up to 30 days.  B. Nationally Covered Indications   The following indications are covered nationally unless otherwise indicated:   1. Computer analysis of EKGs when furnished in a setting and under the circumstances required for coverage of other EKG services.   2. EKG services rendered by an IDTF, including physician review and interpretation.  Separate physician services are not covered unless he/she is the patients attending or consulting physician.  3. Emergency EKGs (i.e., when the patient is or may be experiencing a life -threatening event) performed as a laboratory or diagnostic service by a portable x- ray supplier only when a physician is in attendance at the time the service is performed or immediate ly thereafter.   4 Home EKG services with documentation of medical necessity.  5. Transtelephonic EKG transmissions (effective March 1, 1980) as a diagnostic service for the indications described below, when performed with equipment meeting the standards de scribed below, subject to the limitations and conditions specified below.  Coverage is further limited to the amounts payable with respect to the physicians service in interpreting the results of such transmissions, including charges for rental of the equipment. The device used by the beneficiary is part of a total diagnostic system and is not considered DME separately.  Covered uses are to:   a. Detect, characterize, and document symptomatic transient arrhythmias;   b. Initiate, revise, or discontinue arrhythmic drug therapy; or,   c. Carry -out early post -hospital monitoring of patients discharged after myocardial infarction (MI); (only if 24 -hour coverage is provided, see C.5. below).   Certain uses other than those specified above may be covered if, in the judgment of the local A/B MAC, such use is medically necessary.   Additionally, the transmitting devices must meet at least the following criteria:  a. They must be capable of transmitting EKG Leads, I, II, or III; and,   b. The tracing must be sufficiently comparable to a conventional EKG.   24-hour attended coverage used as early post -hospital monitoring of patients discharged after MI is only covered if provision is made for such 24- hour attended coverage in the manner described below:   24-hour attended coverage means there must be, at a monitoring site or central data center, an EKG technician or other non- physician, receiving calls and/or EKG data; tape recording devices do not meet this requirement. Further, such technicians should have immediate, 24 -hour access to a physician to review transmitted data and make clinical decisions regarding the patient.  The technician should also be instructed as to when and how to contact available facilities to assist the patient in case of emergencies.   C. Nationally N on-Covered Indications   The following indications are non- covered nationally unless otherwise specified below:   1. The time -sampling mode of operation of ambulatory EKG cardiac event monitoring/recording.  2. Separate physician services other than those re ndered by an IDTF unless rendered by the patients attending or consulting physician.  3. Home EKG services without documentation of medical necessity.  4. Emergency EKG services by a portable x- ray supplier without a physician in attendance at the time of  service or immediately thereafter.   5. 24-hour attended coverage used as early post -hospital monitoring of patients discharged after MI unless provision is made for such 24- hour attended coverage in the manner described in section B.5. above.