ModifiedPremera BluecrossPolicy 2.02.510

Mobile Cardiac Outpatient Telemetry and Implantable Loop Recorders

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Defines medical necessity, site-of-service considerations, documentation, and coding for implantable loop recorders (ILRs) and mobile cardiac outpatient telemetry (MCOT) for outpatient cardiac rhythm monitoring.

Policy Summary

PayerPremera Bluecross

PolicyMobile Cardiac Outpatient Telemetry and Implantable Loop Recorders

Policy CodePolicy 2.02.510

Change TypeModified — added ILR coverage criteria, codes, and prior monitoring requirement

Effective DateAug 7, 2026

Last ReviewJun 1, 2026

Next Review DateAug 7, 2026

Key ActionObtain and document at least 14 continuous days of non-diagnostic ambulatory cardiac monitoring before ILR placement and submit prior authorization when required.

SourceLink

POLICY UPDATE CHANGES

Added implantable loop recorders as medically necessary when criteria are met.

Added CPT code 33285, and HCPCS codes C1764, E0616.

Added requirement that ILR placement be preceded by a prior non-diagnostic or inconclusive ambulatory cardiac monitoring of at least 14 continuous days.

Expanded not medically necessary policy statement to include ILRs and monitoring of asymptomatic individuals.

Clarified that site-of-service review is only for implantable loop recorders and added header indicating site-of-service review does not apply to IHS facilities.

14 daysminimum prior monitoring

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ModifiedPremera BluecrossPolicy 2.02.510

Mobile Cardiac Outpatient Telemetry and Implantable Loop Recorders

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Policy Summary

PayerPremera Bluecross

PolicyMobile Cardiac Outpatient Telemetry and Implantable Loop Recorders

Policy CodePolicy 2.02.510

Change TypeModified — added ILR coverage criteria, codes, and prior monitoring requirement

Effective DateAug 7, 2026

Last ReviewJun 1, 2026

Next Review DateAug 7, 2026

Key ActionObtain and document at least 14 continuous days of non-diagnostic ambulatory cardiac monitoring before ILR placement and submit prior authorization when required.

SourceLink

POLICY UPDATE CHANGES

Added implantable loop recorders as medically necessary when criteria are met.

Added CPT code 33285, and HCPCS codes C1764, E0616.

Added requirement that ILR placement be preceded by a prior non-diagnostic or inconclusive ambulatory cardiac monitoring of at least 14 continuous days.

Expanded not medically necessary policy statement to include ILRs and monitoring of asymptomatic individuals.

Clarified that site-of-service review is only for implantable loop recorders and added header indicating site-of-service review does not apply to IHS facilities.

14 daysminimum prior monitoring

syncope, palpitationsprimary symptoms

cryptogenic strokecryptogenic stroke indication

Dec 2, 2025literature reviewed through

Coverage Criteria for ILR and MCOT

Medical necessity criteria for ILR and MCOT

Covered when ALL of the following are met for ILR or MCOT as specified:

Baseline requirement: Prior non-diagnostic or inconclusive ambulatory cardiac monitoring of at least 14 continuous days has been performed>=14 days

Applies to ILR and to MCOT when specified

Symptom indications: Unexplained recurrent episodes of presyncope, syncope, palpitations, or dizzinessFor MCOT: symptoms occurring less frequently than once every 48 hours

MCOT requires symptoms occurring less frequently than once every 48 hours; prior external monitoring must be non-diagnostic

Cryptogenic stroke indication: Evaluation for suspected atrial fibrillation as a cause of cryptogenic stroke after a negative standard workup including 24-hour Holter monitoringNegative standard workup incl. 24-hour Holter

Alternative pathway to symptom-based indications

Site-of-service medical necessity for ILR implantation

Site of service criteria for ILR implantation:

Preferred sites: Ambulatory surgical center (ASC); off campus-outpatient hospital/medical center; on campus-outpatient hospital/medical centerN/A

Preferred, safe, and cost-effective sites for elective ILR implantation when criteria met

Exceptions permitting hospital outpatient site: No geographically accessible ASC within 30 miles that can provide necessary care or where the individual's physician lacks privileges; patient age ≤18 years; concomitant service requiring hospital outpatient setting performed same operative session; or clinical conditions increasing perioperative risk (examples: ASA class III+, recent MI <3 months, uncompensated CHF NYHA III/IV)N/A

Provides exceptions allowing hospital outpatient site-of-service

Implantable Loop Recorder (ILR) indications

Coverage considerations described in these sections center on symptom frequency and diagnostic intent; ILRs and MCOT are considered when longer-term monitoring is clinically indicated.

Use ILR when longer monitoring needed: Progression from external event monitors or short-term Holter monitoring to an implantable loop recorder is supported for individuals with infrequent symptoms when shorter-term monitoring was nondiagnosticInfrequent symptoms not captured by 24–48 hour monitoring

Supported by RCTs and observational studies showing higher arrhythmia detection with ILR

MCOT indications and evidence

MCOT may be considered when real-time detection could plausibly change acute management; evidence assesses both detection capability and whether real-time transmission improves outcomes.

MCOT detection advantage: MCOT has higher diagnostic yield for several arrhythmias compared with autotrigger or event monitors in observational studies and an RCT showed higher detection of clinically significant arrhythmias and shorter median time to diagnosisIncreased detection vs event monitors; earlier median diagnosis (example: 7 vs 9 days)

RCT and large database studies report higher yield and shorter time to diagnosis with MCOT, but clinical impact on management varies

Uncertainty about outcome benefit: No randomized studies demonstrate that real-time monitoring (MCOT) reduces cardiac events or mortality; evidence is insufficient that improved detection translates to improved net health outcomesNo demonstrated outcome benefit

Policy states evidence insufficient to determine net health outcome improvement despite increased detection

Atrial fibrillation detection

AF detection is a common rationale for prolonged monitoring in several clinical contexts.

AF detection post-cryptogenic stroke or post-ablation: Prolonged monitoring may be used to detect paroxysmal atrial fibrillation after cryptogenic stroke or after AF ablation to guide anticoagulation and management decisionsParoxysmal AF detection may require >48 hours monitoring

Detection of AF can change anticoagulation decisions; cryptogenic stroke patients often require prolonged monitoring

Medical necessity and appropriate use

Covered when monitoring is selected based on symptom frequency, diagnostic need, and guideline recommendations:

General statement: Outpatient cardiac telemetry/MCOT detects arrhythmias at least as well as ambulatory event monitoring and offers real-time monitoring; however, evidence is insufficient that real-time monitoring improves clinical outcomes or mortality

Supported by RCT and nonrandomized studies; no randomized trials showing outcome benefit specifically from real-time feature

Clinical scenarios supported: Use of MCOT or extended monitoring is reasonable for: (1) patients with infrequent symptoms suggestive of arrhythmia (less frequently than every 48 hours) when Holter or external AEM is nondiagnostic or contraindicated and real-time monitoring is essential for safety and will change immediate management; OR (2) evaluation of cryptogenic stroke suspected due to AF after nondiagnostic 24–48 hour Holter or 48-hour telemetry

Reflects clinical input and guideline recommendations (ACC/AHA/HRS)

Guideline-aligned monitor selection: Select monitor type by symptom frequency and nature: Holter for events within 24–72 hours; extended ambulatory ECG (≈14–30 days) when events are not daily; continuous monitoring (1–14 days) to quantify burden; ILR for recurrent infrequent unexplained syncope or extended detection in cryptogenic stroke

Covered indications per CMS NCD

Ambulatory cardiac monitors are covered when documentation of medical necessity is present. Indications include, but are not limited to:

Covered indications (examples): Detection of symptomatic transient arrhythmias; determination of arrhythmic drug therapy to initiate, revise, or discontinue therapy

Based on CMS national coverage determination; documentation of medical necessity required for coverage

Implantable Loop Recorder (ILR) initial coverage criteria

ILR coverage when ALL of the following are met

ILR prerequisite monitoring: Prior non-diagnostic or inconclusive ambulatory cardiac monitoring of at least 14 continuous days has been performed before ILR placement>=14 days

Additional criterion added effective August 7, 2026

Other uses of MCOT and ILRs are considered not medically necessary when the policy's medical necessity criteria are not met. Examples explicitly stated in the policy include monitoring asymptomatic individuals for risk factors for arrhythmia, assessing the effectiveness of antiarrhythmic medications, or attempting detection of myocardial ischemia by ST‑segment changes.

The document does not provide an explicit list of exclusion criteria beyond the stated not‑medically‑necessary scenarios; no additional formal exclusions are specified in the cited sections.

Randomized trials have demonstrated that MCOT and outpatient cardiac telemetry detect arrhythmias at least as well as ambulatory event monitoring, but no randomized studies have shown that MCOT's real‑time monitoring reduces cardiac events or mortality. Therefore, routine use of MCOT for the purpose of improving clinical outcomes through real‑time monitoring is not supported by randomized evidence.

The policy does not list specific device model inclusions or exclusions. It notes that a comprehensive description of individual devices is beyond the scope of the policy and references FDA product codes (e.g., DSH, DXH, DQK, DSI, MXD, MHX) for regulatory identification.

The site‑of‑service review described in the policy does not apply to Indian Health Services (IHS) facilities; the policy explicitly clarifies that this operational note limits site‑of‑service review applicability for implantable loop recorder procedures.

When the site‑of‑service criteria for elective surgical procedures are not met, the specified sites of service are considered not medically necessary. The policy identifies preferred outpatient sites (e.g., ambulatory surgical center, off‑campus or on‑campus outpatient hospital) and lists circumstances in which hospital outpatient care may be required; if those site criteria are not satisfied, the chosen site of service for ILR implantation or related elective procedures may be deemed not medically necessary.

Although MCOT increases arrhythmia detection in many studies, the policy concludes that the evidence is insufficient to demonstrate that MCOT's real‑time monitoring improves net health outcomes such as reductions in cardiac events or mortality despite higher detection rates.

Use of MCOT solely for the purpose of improving outcomes by providing real‑time monitoring is considered investigational/insufficient because the current evidence does not establish that real‑time transmission leads to improved clinical outcomes.

The policy's not‑medically‑necessary statements were expanded to explicitly include implantable loop recorders and the use of ambulatory monitoring for asymptomatic individuals in the outlined circumstances where the medical necessity criteria are not met.

Coding and Monitoring Durations

Covered CPT Codes (examples listed)CPTCovered

33285

Insertion, subcutaneous cardiac rhythm monitor, including program.

93228

External mobile cardiovascular telemetry with electrocardiographic recording, concurrent computerized real-time data analysis and greater than 24 hours of accessible ECG data storage (retrievable with query) with ECG triggered and patient selected events transmitted to a remote attended surveillance center for up to 30 days; review and interpretation with report by a physician or other qualified health care professional.

Covered HCPCS Codes / SuppliesHCPCSCovered

C1764	Event recorder, cardiac (implantable).
E0616	Implantable cardiac event recorder with memory, activator, and programmer.

Device examples (no billing codes provided in this section)mixed

No codes listed

FDA product codesmixed

DSH	FDA product code for certain cardiac monitoring devices
DXH	FDA product code for certain cardiac monitoring devices
DQK	FDA product code for certain cardiac monitoring devices
DSI	FDA product code for certain cardiac monitoring devices
MXD	FDA product code for certain cardiac monitoring devices
MHX	FDA product code for certain cardiac monitoring devices

FDA product codesmixed

DSH	FDA product code (ambulatory cardiac monitor category)
DXH	FDA product code (ambulatory cardiac monitor category)
DQK	FDA product code (ambulatory cardiac monitor category)
DSI	FDA product code (ambulatory cardiac monitor category)
MXD	FDA product code (ambulatory cardiac monitor category)
MHX	FDA product code (ambulatory cardiac monitor category)

Covered CPT Codes (ILR additions)CPTCovered

33285

Insertion of insertable cardiac monitor (ILR)

Covered HCPCS CodesHCPCSCovered

C1764	Implantable loop recorder device (HCPCS)
E0616	External mobile cardiac telemetry device (HCPCS)

inv-25: Minimum prior external monitoring duration

Minimum prior external monitoring duration>= 14 continuous days

Applies toPrior non-diagnostic or inconclusive ambulatory cardiac monitoring before ILR placement or for MCOT when specified

Documentation requiredMedical records must document at least 14 continuous days of prior external ambulatory monitoring with a non-diagnostic outcome

inv-26: Monitoring duration examples

Holter monitor typical duration24–72 hours

Provider Actions, Prior Authorization, and Documentation

Prior Authorization

Obtain prior authorization for ILR insertion and MCOT use

Prior authorization or medical necessity review is required for insertion of implantable loop recorders (CPT 33285) and for mobile cardiac outpatient telemetry (MCOT, e.g., 93228) when used to evaluate syncope, palpitations, dizziness, or suspected atrial fibrillation after cryptogenic stroke; site-of-service review applies to ILR implantation. Providers must follow payer prior-authorization processes for these codes and procedures.

Prior authorization/site-of-service review may be required for ILR procedures (CPT 33285) and associated device codes.
MCOT requires prior authorization or medical necessity review when used for evaluation of syncope, palpitations, dizziness, or suspected AF post-cryptogenic stroke.

Prior Authorization

Reference ILR and MCOT-specific prior authorization pathways

The policy centers its prior-authorization focus on implantable loop devices and mobile cardiac outpatient telemetry (MCOT); providers should submit prior-authorization requests referencing the ILR/MCOT-specific criteria and the applicable procedure/device codes.

Definitions and Device Types

inv-49: Implantable Loop Recorder (ILR) definition

DefinitionA subcutaneous device that provides long-term automatic rhythm surveillance over months to years to detect intermittent or abnormal heart rhythms

FunctionRecords and stores cardiac rhythm data automatically; used for detection of infrequent symptomatic arrhythmias and cryptogenic stroke workup

DeploymentImplanted subcutaneously and may be auto-activated or patient-activated; provides prolonged outpatient monitoring beyond external devices

inv-50: Mobile Cardiac Outpatient Telemetry (MCOT) definition

DefinitionAn external device that provides continuous heart rhythm data transmitted to remote monitoring centers with near real-time analysis and clinician notification

Features

Background and Evidence Summary

ILRs and MCOT are outpatient cardiac rhythm monitoring technologies used to detect intermittent arrhythmias such as atrial fibrillation, bradycardia, and tachycardia. MCOT provides continuous external telemetry with near‑real‑time data transmission for short‑term monitoring (typically up to ~30 days), while implantable loop recorders (ILRs) are subcutaneously implanted devices that provide long‑term automatic rhythm surveillance over months to years for detection of infrequent or intermittent abnormal rhythms.

Revision History and Policy Changes

2026-08-07policy_effective_dateLatest

Policy effective date for updated coverage that added implantable loop recorders as medically necessary when criteria are met and included new CPT/HCPCS codes and site-of-service review for ILR.

2026-05-01material_change_announced

Policy announced additions effective August 7, 2026: requirement that ILR placement be preceded by prior non-diagnostic or inconclusive ambulatory cardiac monitoring of at least 14 continuous days; expanded not medically necessary determinations to include ILRs and monitoring of asymptomatic individuals.

Policy Summary

PayerPremera Bluecross

PolicyMobile Cardiac Outpatient Telemetry and Implantable Loop Recorders

Policy CodePolicy 2.02.510

Change TypeModified — added ILR coverage criteria, codes, and prior monitoring requirement

Effective DateAug 7, 2026

Last ReviewJun 1, 2026

Next Review DateAug 7, 2026

Key ActionObtain and document at least 14 continuous days of non-diagnostic ambulatory cardiac monitoring before ILR placement and submit prior authorization when required.

SourceLink

On This Page

Summarizes guideline-recommended selection and sequencing

Extended continuous/patched devicesTypically 14–30 days (eg, patch ECG monitors)

MCOT monitoring reported durationsReported mean/typical monitoring periods ~20–28 days (studies report mean ~21 days)

inv-27: Prior ambulatory monitoring duration

Prior ambulatory monitoring duration required before ILRAt least 14 continuous days of prior external ambulatory cardiac monitoring that was non-diagnostic or inconclusive

Effective date for criterionAdded as requirement effective August 7, 2026 (provider notification noted)

PurposePrerequisite to demonstrate nondiagnostic shorter-term monitoring before proceeding to implantable loop recorder

Policy criteria explicitly apply to implantable loop devices and MCOT device classes.
Include the relevant procedure and HCPCS/CPT codes with authorization requests.

Prior Authorization

Ensure medical necessity is documented for coverage

Coverage for ambulatory cardiac monitors (including external monitors, MCOT, and ILR) requires documentation of medical necessity per the CMS national coverage determination; prior authorization may be required by the payer.

Ambulatory cardiac monitors are covered when medical necessity is documented (CMS NCD).
Payers may require prior authorization per their processes.

Documentation Required

Tie coverage to documented medical necessity and device type

Ambulatory cardiac monitors and implantable loop recorders are covered only when medical records document medical necessity (e.g., symptomatic transient arrhythmias or guidance of arrhythmic drug therapy); include device classification and indication details in submissions.

Document the clinical indication (e.g., detection of symptomatic transient arrhythmias or to guide arrhythmic drug therapy).
List device type (event recorder, continuous external recorder, external memory loop, MCOT, or ILR) when submitting records.

Prior Authorization

Obtain site-of-service review and document prerequisite monitoring for ILR

Prior authorization/site-of-service review may be required for ILR procedures and associated device codes, and ILR coverage requires a prior external ambulatory cardiac monitoring trial of at least 14 continuous days that was non-diagnostic or inconclusive.

Site-of-service review applies to ILR implantation (see ASC/hospital site criteria).
Document prior external ambulatory monitoring of at least 14 continuous days with a non-diagnostic result before ILR placement.

Step Therapy

Document prior external monitoring ≥14 continuous days before ILR

Before implanting an ILR, providers must document a prior external ambulatory cardiac monitoring trial of at least 14 continuous days that was non-diagnostic; this prerequisite is required to support medical necessity for ILR placement.

Prior external monitoring must be continuous for at least 14 days and be non-diagnostic or inconclusive.
This 14-day requirement was added as an ILR criterion effective August 7, 2026.

Step Therapy

Progress diagnostically from external monitors to ILR when needed

Use ILR after nondiagnostic shorter-term external monitors when longer-term surveillance is needed; evidence and clinical guidance support progression from external event monitors to implantable loop recorders for infrequent symptoms.

Progress from Holter or external event monitor to ILR when symptoms are infrequent and shorter monitoring was nondiagnostic.
ILR is indicated for recurrent, infrequent, unexplained syncope per guideline patient-selection recommendations.

Note

Follow guideline-based monitor selection and sequencing

Select and sequence monitors based on symptom frequency and clinical need: use Holter for events within 24–72 hours, extended external monitors for ~14–30 days, MCOT when real-time monitoring is essential, and ILR for recurrent infrequent unexplained syncope or extended AF detection.

Holter: 24–72 hours for frequent symptoms.
Extended continuous devices: typically 14–30 days for less frequent symptoms.
MCOT: consider when real-time detection is essential to change immediate management.
ILR: for long-term surveillance when prior external monitoring is nondiagnostic.

Step Therapy

Confirm prior ambulatory monitoring of ≥14 continuous days before ILR

Before ILR placement, members must have undergone at least 14 continuous days of ambulatory cardiac monitoring that was non-diagnostic or inconclusive; document the monitoring duration and result in the medical record.

Minimum prior external monitoring duration required: ≥14 continuous days.
Record the type of prior monitor and that it was non-diagnostic/inconclusive.

Documentation Required

Include comprehensive documentation of medical necessity in records

Medical records submitted must document that medical necessity criteria are met, including office visit notes with relevant history and physical, documentation of symptoms (presyncope, syncope, palpitations, dizziness), prior monitoring details, and results.

Include office visit notes with history and physical exam.
Document symptom frequency and details and prior monitoring type/duration and results (e.g., 24-hour Holter negative, ≥14-day external monitoring non-diagnostic).

Documentation Required

Record device class and specific device type

Document the device class and specific device type in the record (e.g., event recorder, continuous external recorder, external memory loop, MCOT, or implantable loop recorder) as listed in Table 1.

Identify device class and example device when applicable (Table 1).
State whether the device is patient-activated, auto-activated, continuous external, MCOT, or implantable.

Documentation Required

Document the indication and medical necessity clearly

Document that monitoring is medically necessary to detect symptomatic transient arrhythmias, to guide arrhythmic drug therapy, or to evaluate suspected AF after cryptogenic stroke; absence of such documentation may lead to denial.

State the clinical purpose: detection of symptomatic arrhythmia or to guide medication/procedure decisions.
For cryptogenic stroke evaluation, document a negative standard workup including 24-hour Holter.

Documentation Required

Specify the clinical indication for monitoring in records

Medical records must document the specific indication for monitoring (e.g., detection of symptomatic transient arrhythmias, guidance of arrhythmic drug therapy, or evaluation for AF after cryptogenic stroke) to support coverage.

For AF evaluation after cryptogenic stroke, include documentation of a negative standard workup, including 24-hour Holter monitoring.

Note

Verify member benefits and payer-specific requirements

Verify member benefits and any plan-specific limitations prior to ordering monitoring or ILR implantation; consult the member benefit booklet or contact customer service because coverage and prior-authorization requirements vary and this medical policy does not apply to Medicare Advantage.

Confirm benefit coverage and prior-authorization requirements with member services.
This policy is a guide; member contracts may differ.

Denial Risk

Risk of denial if required criteria or documentation are missing

If criteria are not met (for example, no prior ≥14-day external monitoring when required, absent documentation of symptoms, or incomplete cryptogenic stroke workup), use of MCOT or ILR may be denied; providers should include all supporting documentation in authorization requests to mitigate denial risk.

Denials can occur when prior non-diagnostic monitoring, symptom documentation, or required stroke workup criteria are not demonstrated.
Include prior-monitoring reports, symptom logs, and results of standard AF workup to reduce denial risk.

Note

No single automatic authorization/denial trigger specified

The policy text does not specify a single automatic authorization or denial trigger; determinations should be made based on whether documented medical necessity and the policy criteria are met.

No explicit automatic triggers are listed in the policy.
Decisions rely on review of documented criteria and medical necessity.

Denial Risk

Denial risk if medical necessity documentation is missing

Ambulatory cardiac monitors are covered only when medical necessity is documented; absence of documentation of medical necessity (history, prior monitoring, symptom correlation) may result in claim denial or authorization denial.

Document history, physical, prior monitoring results, and clinical rationale.
Coverage follows CMS NCD guidance requiring documented medical necessity.

Denial Risk

Absence of medical necessity documentation may lead to denial

Lack of documentation that ambulatory cardiac monitoring is medically necessary (e.g., missing prior monitoring reports, absent symptom documentation) may trigger denial; ensure records explicitly state the therapeutic or diagnostic intent.

Clarify whether monitoring is intended to detect symptomatic arrhythmias or to guide drug therapy.
Attach relevant testing results and clinician notes.

Denial Risk

ILR claims may be denied if site-of-service or prior-monitoring criteria are unmet

Claims for implantable loop recorders may be subject to site-of-service review and could be denied if ILR criteria — including prior non-diagnostic ambulatory monitoring of at least 14 continuous days — or site-of-service requirements are not met.

Site-of-service criteria (ASC vs hospital outpatient) must be met or documented exceptions justified.
ILR-specific prerequisite: prior non-diagnostic/inconclusive external monitoring ≥14 days.

Continuously recording or autotriggered memory-loop devices that transmit data to a central recording station for real-time monitoring (up to ~30 days)

Use casesUsed when real-time detection could change immediate management or when events are infrequent and real-time alerts are needed

inv-51: Holter monitor definition

DefinitionA continuously worn device that records cardiac electrical activity for 24 to 72 hours, typically with multiple channels

LimitationsDoes not provide real-time analysis; best for events expected within 24–72 hours

Typical useFirst-line for frequent symptoms occurring daily or within a short window

inv-52: Event recorder (noncontinuous) definition

DefinitionA noncontinuous device not worn continuously and activated by the individual when symptoms occur to store episodic recordings

OperationPatient-activated at symptom onset; stores selected ECG segments for clinician review

Appropriate useUseful when symptoms are sufficiently frequent that the user can activate the recorder during events

inv-53: External memory loop device definition

DefinitionContinuously worn devices that retain a rolling ECG memory and save preceding seconds when activated; may be individual- or autotriggered

FunctionStores single-channel ECG in a refreshed memory loop and records surrounding seconds when triggered

VariantsAvailable as individual-triggered or autotriggered external loop monitors

inv-54: Implantable loop recorder (ILR) — subcutaneously implanted memory loop device definition

DefinitionSubcutaneously implanted memory loop device that can be individual- or autotriggered and provides long-term monitoring

CapabilityRetains long-term rhythm data and can detect infrequent arrhythmias over months to years

Examples (policy table)Reveal XT ICM (Medtronic), Confirm Rx (Abbott), BioMonitor (Biotronik)

inv-55: Mobile cardiac outpatient telemetry (MCOT) — continuously recording/autotriggering device that transmits to monitoring center

DefinitionA continuously recording or autotriggering external device that streams multilead data and transmits to a monitoring center for near real-time analysis and alerts

CharacteristicsMultilead monitoring, autodetection and autosend of events, immediate alarm generation on event detection

Practical noteMay require daily electrode changes and is used when near real-time clinician notification could alter management

inv-56: Mobile cardiac outpatient telemetry (MCOT) alternate description

Alternate descriptionAn ambulatory multilead monitoring system that streams data continuously, can autodetect and autosend events, and generate immediate alarms on event detection

Use caseUsed when continuous streaming and immediate alerts are necessary for patient safety or timely intervention

ExamplesCardioNet MCOT, LifeStar Mobile Cardiac Telemetry, Zio AT

inv-57: Ambulatory cardiac monitors definition

DefinitionAmbulatory cardiac monitors are devices used to detect symptomatic transient arrhythmias and to guide arrhythmic drug therapy; includes Holter, external event/loop recorders, and implantable loop recorders

ScopeUsed outside the hospital setting for outpatient rhythm monitoring

Coverage linkageCoverage depends on documentation of medical necessity per CMS NCD

inv-58: Ambulatory cardiac monitors definition (expanded)

DefinitionDevices that record cardiac rhythm outside the hospital setting, including Holter monitors, external loop/event recorders, MCOT, and implantable loop recorders

Regulatory noteFDA product codes for device categories include DSH, DXH, DQK, DSI, MXD, MHX

IndicationsDetection of symptomatic transient arrhythmias and determination of arrhythmic drug therapy

inv-59: Implantable loop recorder (ILR) — added as a covered technology when policy criteria are met (definition duplicate/new addition)

DefinitionAn implanted device for long-term cardiac rhythm monitoring; policy added ILRs as a covered technology when criteria are met

Policy changeILRs were added as medically necessary when criteria are met and new procedure/device codes were added (CPT 33285, HCPCS C1764, E0616)

Intended useLong-term automatic rhythm surveillance for intermittent arrhythmias not captured by short-term external monitors

material_change_effective

Changes effective April 8, 2026 (after provider notification) adding implantable loop recorders as medically necessary when criteria are met and adding CPT code 33285 and HCPCS codes C1764 and E0616; added site-of-service ASC consideration for ILR.

2026-06-01minor_update

Minor update recorded June 1, 2026 clarifying site-of-service review applicability and adding header that site-of-service review does not apply to Indian Health Services (IHS) facilities.

2024-08-01interim_review

Interim review (approved July 8, 2024) updated literature through April 9, 2024; policy statements unchanged at that time.

2024-02-01interim_review

Interim review (approved January 9, 2024) added policy criteria classifying MCOT as medically necessary rather than investigational.