Ambulatory Event Monitors and Mobile Cardiac Outpatient Telemetry
There are a wide variety of devices available for outpatient cardiac rhythm monitoring. The primary purpose of these devices is the evaluation of suspected arrhythmias that have not been detected by office- or hospital-based monitoring. These devices differ in the types of monitoring leads used, the duration and continuity of monitoring, the ability to detect arrhythmias without patient intervention, and the mechanism of delivery of the information from patient to clinician.
Continuous Monitoring Devices (Holter monitors and similar devices)
Ambulatory Holter electrocardiography (EKG) is a widely used noninvasive test in which the EKG is continuously recorded over an extended period of time, typically 24 to 48 hours, in order to evaluate symptoms suggestive of cardiac arrhythmias; i.e., palpitations, dizziness, or syncope. However, Holter monitoring will be ineffective if a patient experiences infrequent symptoms. Therefore, the sensitivity of Holter monitoring is low for detection of arrhythmias that are intermittent.
Continuous Monitoring Devices with Longer Recording Periods
Some newer devices are continuous monitors that are similar to traditional Holter monitoring in concept, but offer other advantages such as the ability to monitor for longer periods of time.
Non-Continuous Monitoring Devices (ambulatory event monitors and similar devices)
Ambulatory event monitors (AEMs) were developed to provide longer periods of monitoring. In this technique the recording device is either worn continuously, and activated only when the patient experiences symptoms, or is carried by the patient and applied and activated when symptoms are present. The recorded EKGs are then either stored for future analysis or transmitted by telephone to a receiving station; e.g., a doctor's office, hospital, or to a cardiac monitoring service, where the EKGs can then be analyzed. AEMs can be used for extended periods of time, typically up to a month until the patient experiences symptoms. Since the EKGs are recorded only during symptoms, there is good correlation with any underlying arrhythmia. Conversely, if no EKG abnormality is noted, a non-cardiac etiology of the patient's symptoms can be sought.
Several different types of AEMs are available:
1. Noncontinuous devices with memory
2. Continuous "memory loop" devices
These sophisticated devices are able to continuously store a single channel of EKG data in a refreshed memory. If the patient activates the device, the EKG is then recorded from the memory loop for the preceding 30 to 90 seconds, and for the next minute or so. Therefore, these types of devices permit recording of the onset of arrhythmias and/or transient or incapacitating events. They obviously must be worn continuously.
3. Implantable continuous "memory loop" devices
An implantable loop recorder device is inserted just under the patient's skin in the chest area during an outpatient surgical procedure. When symptoms are felt, the patient places a hand-held activator over the recorder to activate the storage of cardiac rhythms. This device can be used for more than one year. The Reveal® Insertable Loop Recorder is a recently FDA-approved implantable memory loop device.
4. Auto-triggered devices
All of these devices require activation by the patient. More recently, auto-triggering technology has become available, which can be adapted to memory loop devices. For example, event monitors can be programmed to detect heart rates greater than 165 beats per minute, less than 40 beats per minute, or an asystole of greater than 3 seconds.
5. Implantable continuous “memory loop” devices with autotrigger
These devices combine the long-term monitoring available with implantable devices with the autotriggers seen on newer event monitors. These devices contain algorithms that are programmed to detect heart rates exceeding an upper or lower limit, asystole of greater than 3 seconds. They typically contain other autotriggers, such as a variable RR interval seen with atrial fibrillation.
Mobile Outpatient Cardiac Telemetry
Ambulatory event monitors store the recorded data, which is ultimately transmitted either to a physician's office or to a central recording station. In contrast, outpatient cardiac telemetry provides real time monitoring and analysis. For example, CardioNet® Inc. is a company that offers Mobile Cardiac Outpatient Telemetry. In this system, the patient wears a three lead sensor, which constantly communicates with the CardioNet® monitor, a light weight unit that can be carried in a pocket or a purse. When an arrhythmia is detected according to preset parameters, the EKG is automatically transmitted to a central CardioNet® service center, where the EKG is immediately interpreted, with results sent to the referring physician. The referring physician can request the level and timing of response, ranging from daily reports to stat results. Other systems for outpatient cardiac telemetry include the HEARTLink II system (Cardiac Telecom Corp.), the VST (Vital Signs Transmitter, Biowatch Medical), and the Lifestar ambulatory cardiac telemetry (ACT) system (Card Guard Scientific Survival Ltd). The CardioNet system has a built-in cellular telephone that automatically transmits signals when the patient is away from home.
The VectraplexECG System is a real-time continuous Mobile Cardiac Outpatient Telemetry device to measure ischemic ECG changes that can be indicative of a myocardial infarction (MI). This device utilizes the Internet to communicate real-time ECG changes to the physician. The patient is hooked up to a mini-tablet by either 5 electrodes, which communicate 15-lead ECG data, or 10 electrodes that communicate 12-lead ECG data. While this system is primarily intended to monitor for ischemia, the continuous ECG monitoring would presumably detect rhythm disturbances, as well as ischemic changes.
The use of patient-activated or auto-activated external ambulatory event monitors may be considered medically necessary as a diagnostic alternative to Holter monitoring in the following situations:
The use of implantable ambulatory event monitors, either patient activated or auto-activated, may be considered medically necessary only in the small subset of patients who experience recurrent symptoms so infrequently that a prior trial of Holter monitor and other external ambulatory event monitors has been unsuccessful.
Outpatient cardiac telemetry (also known as mobile cardiac outpatient telemetry or MCOT) is considered not medically necessary as a diagnostic alternative in patients who experience infrequent symptoms (less frequently than every 48 hours) suggestive of cardiac arrhythmias (i.e., palpitations, dizziness, presyncope, or syncope).
Continuous ambulatory monitors that record and store information for periods longer than 48 hours are considered investigational.
Other uses of ambulatory event monitors, including outpatient cardiac telemetry, are considered investigational, including but not limited to monitoring effectiveness of antiarrhythmic therapy, for patients with cryptogenic stroke, and detection of myocardial ischemia by detecting ST segment changes.
Investigative service is defined as the use of any treatment procedure, facility, equipment, drug, device, or supply not yet recognized by certifying boards and/or approving or licensing agencies or published peer review criteria as standard, effective medical practice for the treatment of the condition being treated and as such therefore is not considered medically necessary.
The coverage guidelines outlined in the Medical Policy Manual should not be used in lieu of the Member's specific benefit plan language.
2/1999: Implantable Continuous "Memory Loop" Devices policy approved by Medical Policy Advisory Committee (MPAC), CPT 33999 added
5/1999: MPAC expanded and renamed policy to include all Ambulatory Event Monitors
1/23/2002: Prior authorization deleted
2/15/2002: Investigational definition added
4/18/2002: Type of Service and Place of Service deleted
5/23/2002: Code Reference section updated, CPT 93012, 93014 added
8/4/2003: Code Reference section updated, HCPCS G0004-G0007, G00015 deleted
10/21/2004: Code Reference section updated, CPT 33999, 93012, 93014 deleted, CPT 93270, 93271, 93272 description revised, ICD-9 procedure code 86.05, 86.09 description revised, HCPCS G0015 deleted
10/25/2005: Policy clarified and re-titled
03/07/2006: Coding updated. HCPCS 2006 revisions added to policy
09/12/2006: Coding updated. ICD9 2006 revisions added to policy
1/3/2007: Policy reviewed, policy section clarified
5/11/2007: Policy reviewed. Policy section updated; no change to policy statements
12/24/2008: Coding reference section updated per the 2009 CPT/HCPCS revisions
5/14/2009: Outpatient cardiac telemetry (MCOT) changed from "investigational" to "not medically necessary"
04/12/2010: Description section revised with other outpatient cardiac telemetry systems. Coding Section revised to add CPT Codes 93228 and 93229 and ICD-9 Diagnosis codes 427.0, 427.1, 427.2, 427.31, 427.32, 427.41, 427.42, 427.61, 427.69 and 427.81 to the Covered Codes Table. Also identified HCPCS Codes S0345, S0346 & S0347 were deleted as of 12/31/2009.
10/21/2010: Policy reviewed; no changes.
03/10/2011: Added ICD-9 code 785.0 to the Covered Codes table.
01/17/2012: Added the following policy statement: The use of auto-activated external ambulatory event monitors may be considered medically necessary in patients treated for atrial fibrillation to monitor for asymptomatic episodes in order to evaluate treatment response. Deleted outdated references from the Sources section. Removed deleted HCPCS codes S0345, S0346, and S0347 from the Code Reference section.
02/20/2013: Policy description updated regarding available devices. Policy statement revised to add patients with cryptogenic stroke to the last investigational statement. Added the following policy statement: Continuous ambulatory monitors that record and store information for periods longer than 72 hours are considered investigational. The first policy statement was re-worded to add patient-activated or auto-activated monitors. The policy statement regarding use of event monitors in patients with atrial fibrillation treated with catheter ablation was revised for clarity purposes.
04/22/2014: Policy statement revised to state that continuous ambulatory monitors that record and store information for periods longer than 48 hours are considered investigational. It previously stated longer than 72 hours.
Blue Cross Blue Shield Association Policy #2.02.08
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.