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ModifiedBluecross IdahoPolicy MP 2.02.08

Ambulatory Event Monitors and Mobile Cardiac Outpatient Telemetry

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Defines medical necessity criteria and coverage guidance for external and implantable ambulatory event monitors and mobile cardiac outpatient telemetry (MCOT) as alternatives to Holter monitoring for diagnosis and monitoring of cardiac arrhythmias, affecting providers ordering or supplying these monitoring services for Blue Cross of Idaho members.

Policy Summary

PayerBluecross Idaho

PolicyAmbulatory Event Monitors and Mobile Cardiac Outpatient Telemetry

Policy CodePolicy MP 2.02.08

Change TypeRevised coverage stance for MCOT

Effective DateJun 1, 2026

Last ReviewFeb 26, 2026

Next Review DateFeb 26, 2026

Key ActionDocument that symptoms are infrequent, prior Holter/AEM was nondiagnostic, and that real-time monitoring is essential for patient safety when requesting MCOT.

SourceLink

POLICY UPDATE CHANGES

The policy statement was revised to allow MCOT as medically necessary for certain patients with infrequent symptoms when specific criteria are met, replacing a prior investigational stance.

48 hrsmonitoring duration threshold used to distinguish Holter from longer-term monitors

24-72typical Holter monitor recording period

8.9%AF detection ICM vs routine care (CRYSTAL AF)

10%estimated cryptogenic stroke AF proportion

Dec 2, 2025literature update through

Coverage Criteria — Ambulatory Event Monitoring & MCOT

External/continuous ambulatory monitors (medical necessity)

Covered when ANY of the following situations apply:

External long-term monitoring indications: 1) Individuals who experience infrequent symptoms (less frequently than every 48 hours) suggestive of cardiac arrhythmias (palpitations, dizziness, presyncope, or syncope). 2) Individuals with atrial fibrillation who have been treated with catheter ablation and in whom discontinuation of systemic anticoagulation is being considered. 3) Individuals with cryptogenic stroke who have a negative standard workup for AF including a 24‑hour Holter monitor.symptoms < every 48 hours or prior 24-hour Holter negative

Policy: external patient‑activated or auto‑activated event monitors or continuous ambulatory monitors recording >48 hours may be considered medically necessary as an alternative to Holter monitoring.

Implantable ambulatory event monitors (medical necessity)

Covered when ALL of the following are met:

Implantable monitor indications:

Policy Summary

PayerBluecross Idaho

PolicyAmbulatory Event Monitors and Mobile Cardiac Outpatient Telemetry

Policy CodePolicy MP 2.02.08

Change TypeRevised coverage stance for MCOT

Effective DateJun 1, 2026

Last ReviewFeb 26, 2026

Next Review DateFeb 26, 2026

Key ActionDocument that symptoms are infrequent, prior Holter/AEM was nondiagnostic, and that real-time monitoring is essential for patient safety when requesting MCOT.

SourceLink

On This Page

1) Prior trial(s) of external ambulatory event monitors (patient‑ or auto‑activated) have been unsuccessful in capturing suspected arrhythmia because symptoms are very infrequent; AND 2) The clinician documents that long‑term continuous monitoring is required to detect arrhythmia (for example, when prolonged surveillance for AF is needed after cryptogenic stroke or to evaluate infrequent syncope/presyncope); AND 3) The anticipated monitoring duration or clinical context justifies an implantable device rather than repeat external monitoring.

failure of external monitoring or clinical need for long-term monitoring

ILR may be reasonable as initial strategy only when likelihood of needing long‑term monitoring is high; use aligns with diagnostic progression from external monitor to ILR.

Outpatient cardiac telemetry / MCOT (medical necessity)

Covered when ALL of the following are met:

MCOT criteria group A: Evaluation of recurrent unexplained clinically significant presyncope, syncope, severe palpitations or dizziness when: (a) symptoms are thought to be due to a cardiac arrhythmia as the most likely diagnosis; AND (b) Holter monitor and/or external AEM has been nondiagnostic or contraindicated; AND (c) documentation that real‑time monitoring is essential for patient safety and will lead to immediate clinical changes such as medication adjustment or emergent procedures.all conditions a-c must be met

Real‑time transmission must be documented as essential for patient safety and expected to change immediate management.

MCOT criteria group B: Evaluation of cryptogenic stroke thought to be caused by atrial fibrillation when a prior 24‑ to 48‑hour Holter monitor or 48‑hour telemetry was nondiagnostic; extended monitoring (including MCOT) may be used to detect occult AF to inform anticoagulation decisions.prior 24-48 hour Holter non-diagnostic

Policy recognizes longer monitoring increases AF detection after cryptogenic stroke.

Long-term ambulatory event monitoring — symptomatic patients

Covered when ALL of the following are met

Primary clinical indication: Patient has signs or symptoms suggestive of arrhythmia (eg, palpitations, syncope, dizziness, near‑syncope).

Relevant population: individuals with signs or symptoms suggestive of arrhythmia.

Intervention considered: Use of patient‑ or auto‑activated external event monitoring or continuous ambulatory event monitoring (devices worn continuously and recording longer than Holter).monitoring duration >48 hours

Continuous event monitors record continuously and store data longer than Holter.

Comparator context: ECG or 24–48 hour Holter monitoring considered as initial alternatives; extended monitoring is expected to increase diagnostic yield beyond these comparators.prior short-term monitoring nondiagnostic when applicable

Holter monitors typically used for 24–72 hours; consider stepwise progression from short to longer monitoring.

Situations where identification of arrhythmia is considered a reasonable endpoint

Examples of clinical situations where AEMs may be clinically meaningful

Management-impacting scenarios: Detection of arrhythmia that leads to interventions known to improve outcomes, e.g., implantation of an ICD for potentially lethal ventricular arrhythmias; initiation or adjustment of antiarrhythmic therapy or pulmonary vein isolation for atrial fibrillation; initiation of anticoagulation after AF detection post‑ablation or after cryptogenic stroke.

Identification of arrhythmia is a reasonable endpoint when it changes management (see post‑ablation and cryptogenic stroke contexts).

General coverage rationale

Covered when monitoring is expected to change management by detecting arrhythmia beyond the timeframe of standard Holter monitoring

Primary coverage logic: Long‑term or continuous ambulatory monitoring is supported when detection of arrhythmias beyond 24–48 hours would alter therapy (for example, initiation or discontinuation of anticoagulation, initiation or change of antiarrhythmic therapy, device implantation, or ablation planning).monitoring duration >48 hours or clinical indication for extended surveillance

Observational evidence and systematic reviews show extended monitoring increases arrhythmia detection and leads to management changes that are expected to improve outcomes.

Surveillance after AF ablation

Covered when ALL of the following are met

Post-ablation surveillance: Individual has undergone AF catheter ablation and clinician documents the need for objective rhythm surveillance to determine presence or absence of recurrent AF to guide anticoagulation decisions beyond the initial 3‑month postprocedure period.post‑ablation surveillance beyond initial anticoagulation period

Late and often asymptomatic recurrences occur; detection informs thromboembolic risk and anticoagulation management.

Covered clinical indications

Covered when monitoring is intended to detect AF to inform management in the following populations:

Populations with supporting evidence: Individuals post–AF ablation for detection of recurrence; individuals with cryptogenic stroke with negative standard workup for AF; selected asymptomatic individuals at higher risk where detection may inform anticoagulation decisions.

Evidence shows longer monitoring increases AF detection and often leads to anticoagulation or other management changes.

Evidence and limitations

Coverage considerations and limitations

Evidence summaries: Longer monitoring increases AF detection rates; multiple RCTs and observational studies demonstrate higher detection with extended monitoring, and detections often lead to management changes. However, randomized trials have had heterogeneous results on downstream clinical outcomes (e.g., stroke reduction), and device heterogeneity precludes establishing a single superior device. Direct RCT evidence that real‑time transmission (MCOT) improves patient outcomes is limited or lacking.

Limitations include trial heterogeneity, limited power for clinical outcomes, and mixed results in screening trials.

Long-term monitoring for cryptogenic stroke/TIA

Covered when ALL of the following are met (evidence-based rationale):

Long-term monitoring after cryptogenic stroke - evidence summary: Long‑term ambulatory cardiac monitoring (external auto‑triggered ELR, patch monitors, or implantable loop recorders) is associated with higher AF detection rates compared with short‑term Holter monitoring in patients with cryptogenic ischemic stroke or TIA; most detected AF leads to anticoagulation initiation and, by the chain‑of‑evidence, is expected to improve stroke prevention outcomes.

Supported by RCTs including CRYSTAL AF, Gladstone et al, and Kaura et al; device type not uniquely established as superior.

Screening asymptomatic individuals at risk for AF

Consider (evidence limited) when ALL of the following apply for asymptomatic individuals:

Asymptomatic individuals with risk factors: Patient is asymptomatic but has risk factors for AF and monitoring is intended to detect occult AF to inform management; however, evidence that screening improves clinical outcomes is limited and trials have mixed results, so screening should be considered only when clinical rationale and potential management changes are documented.

RCTs detect more AF and increased anticoagulation initiation but have not consistently shown stroke reduction; USPSTF and large trials provide limited support for routine screening in unselected populations.

Evidence-based coverage considerations

Evidence summary — monitoring increases AF detection but impact on clinical outcomes is mixed

Increased diagnostic yield: Multiple randomized controlled trials and observational studies demonstrate that ambulatory monitoring detects more AF than usual care or short‑term monitoring, and that monitoring increases initiation of anticoagulation.

Trials include REHEARSE‑AF, Gladstone, CRYSTAL AF, LOOP, and others.

Clinical outcome impact: Some pooled analyses including ILR trials suggested modest stroke/systemic embolism reduction when considering all trials, but trials using only noninvasive monitors did not show stroke benefit; overall, trials were often underpowered or heterogeneous for clinical outcomes.

Meta‑analyses (e.g., Langen et al) and individual large trials (LOOP, STROKESTOP) inform these conclusions.

Downstream management changes: Ambulatory monitoring leads to increased anticoagulant initiation and changes in management (e.g., pacemaker implantation) in several studies, indicating downstream clinical actions following detection.

Management changes documented in RCTs and observational series (Gladstone, mSToPS, CRYSTAL AF).

Clinical coverage considerations

Coverage considerations and clinical indications summarized from evidence review:

ILR use for infrequent symptoms: ILR is intended for individuals with signs or symptoms suggestive of arrhythmia with infrequent events where longer‑term monitoring is required; ILR has higher diagnostic yield than short‑term monitors and may be appropriate when the probability of needing long‑term monitoring is high.infrequent symptoms (< every 48 hours)

Diagnostic progression from external event monitor to ILR is supported; ILR may be initial strategy when long‑term monitoring likely needed.

Diagnostic progression: Progression from external event monitoring to ILR is appropriate when longer monitoring is needed; external AEMs are acceptable initial comparators unless ILR is clearly indicated.N/A

Trials and guideline recommendations support a stepwise approach.

Evidence requirements: Clinical validity studies should report sensitivity/specificity or diagnostic yield; clinical utility studies should demonstrate how results impacted treatment decisions and patient management.reporting of diagnostic performance or diagnostic yield; demonstration of management impact

Absence of these data may render a test unproven or investigational.

Evidence-based coverage considerations

Evidence summaries and implications for use of ILRs, AEMs, and MCOT in patients with symptoms suggestive of arrhythmia:

ILR clinical validity: Randomized trials and systematic reviews demonstrate higher diagnostic yield and AF detection rates for ILRs compared with external monitoring in patients with unexplained syncope or infrequent palpitations.see RCT results

Systematic reviews (Solbiati, Afzal) and RCTs support ILR diagnostic performance.

Clinical utility inference: Observational studies report downstream management changes (anticoagulation initiation, device implantation) after diagnoses from ILR; because those treatments are effective, long‑term monitoring with ILRs is inferred to improve health outcomes even when direct RCT outcome data are limited.N/A

Chain‑of‑evidence approach applied.

MCOT evaluation needs: Assessment of MCOT requires demonstration of both device detection capability and that real‑time transmission confers incremental clinical benefit (i.e., that immediate notifications change management and improve outcomes).N/A

Direct outcome studies (not just detection rates) are needed to support broad clinical utility of MCOT.

Study selection for validity/utility: Studies used to evaluate devices should report sensitivity, specificity, predictive values, or diagnostic yield for validity; to assess utility, studies must show impact on treatment decisions and patient outcomes.N/A

Explicit study selection criteria described in policy.

Evidence requirements

Coverage considerations depend on demonstration of both device detection capability and incremental clinical benefit from real-time transmission:

Evidence requirements to support MCOT use: (1) Clinical validity demonstrated by sensitivity/specificity or diagnostic yield; AND (2) Clinical utility shown by studies demonstrating that real‑time transmission changes management and improves patient health outcomes (direct evidence preferred from RCTs or strong observational studies).two-component requirement

Policy states need for outcome studies, not just detection rate improvements.

Supporting evidence (detection and time-to-diagnosis)

Findings from clinical studies relevant to coverage assessment:

Empirical findings supporting MCOT: Randomized trial (Rothman et al. 2007) showed higher diagnostic confirmation rates and shorter median time to diagnosis for MCOT versus looping patient‑activated monitors; large observational studies report higher detection rates for AF and other arrhythmias with MCOT and identification of potentially emergent events in ~1% of monitored patients. However, these studies generally do not report downstream clinical outcome benefits tied directly to MCOT use.RCT and observational signals

Time‑to‑diagnosis and higher detection rates are documented but clinical outcome impact of real‑time monitoring remains uncertain.

Coverage stance and clinical criteria

Coverage is nuanced by device type and clinical scenario; summarize evidence-based positions below.

Ambulatory event monitoring (external) - general: Covered when signs/symptoms suggestive of arrhythmia and longer recording (>48 hours) is required because longer monitoring increases diagnostic yield and may affect therapy.>48 hours or as clinically indicated

Evidence sufficient to determine improvement in net health outcome for symptomatic patients and post‑ablation AF monitoring.

Implantable loop recorder (ILR): Covered for patients with infrequent symptoms suggestive of arrhythmia when external monitoring is nondiagnostic and longer‑term monitoring is needed; studies show higher detection than short‑term monitors.infrequent symptoms (< every 48 hrs) or nondiagnostic external monitoring

Evidence sufficient to determine improvement in net health outcome.

Mobile Cardiac Outpatient Telemetry (MCOT): Considered clinically useful for arrhythmia detection and offers real‑time monitoring; however, evidence does not demonstrate a clear incremental improvement in clinical outcomes over ambulatory event monitoring and MCOT may be reasonable in selected patients when real‑time monitoring is essential for patient safety.documentation that real‑time monitoring will change immediate management

One observational study reported lower readmission after stroke with MCOT vs ILR; no RCTs demonstrating management/outcome benefit.

Outpatient cardiac telemetry (real‑time): At least as good as ambulatory event monitoring for arrhythmia detection but insufficient evidence that real‑time monitoring reduces cardiac events or mortality; use in selected patients when clinical input supports need for real‑time surveillance (e.g., recurrent unexplained syncope, presyncope, severe palpitations).clinical justification that real‑time surveillance is needed

Clinical input supports use in appropriately selected subgroup of patients.

Device selection and monitoring duration

Covered when device selection and indication align with guideline recommendations (AHA/ACC/HRS; ISHNE/HRS):

Monitor selection by symptom frequency: Use Holter monitoring when symptoms are frequent enough to be detected within 24–72 hours; use patient‑activated event monitors when symptoms are likely within 2–6 weeks; use extended ambulatory ECG (15–30 days) when symptomatic events are not daily or are uncertain; use continuous monitoring (1–14 days) to quantify arrhythmia burden and patterns.time‑based selection

Policy references AHA/ACC/HRS and ISHNE/HRS guidance for selecting monitor type and duration.

Indications

Covered when monitoring is for guideline-supported indications:

Indications: Unexplained syncope when tachycardia suspected; unexplained palpitations; detection of atrial fibrillation and post‑conversion pauses; cryptogenic stroke to detect undiagnosed atrial fibrillation; detection of symptomatic transient arrhythmias and assessment to guide arrhythmic drug therapy.indication‑based

Recommendations and levels of evidence from ISHNE/HRS and Medicare NCD support these indications.

Covered when ALL of the following are met

Covered when monitoring is intended for detection of suspected arrhythmia after nondiagnostic short-term monitoring or when symptoms are infrequent:

Primary criteria: Evaluation of recurrent unexplained presyncope, syncope, palpitations, or dizziness when: (1) symptoms are thought to be due to a cardiac arrhythmia; AND (2) Holter monitor or 48‑hour telemetry was nondiagnostic or symptoms occur less frequently than once every 48 hours such that arrhythmia is unlikely to be diagnosed by Holter monitoring.symptoms < every 48 hours or prior nondiagnostic Holter/48‑hr telemetry

Clinical input endorses MCOT/extended monitoring for these scenarios to increase diagnostic yield and shorten time‑to‑diagnosis.

Additional appropriate indications: Evaluation of cryptogenic stroke with nondiagnostic Holter/48‑hour telemetry; monitoring arrhythmia status following ablation; nocturnal arrhythmia (e.g., associated with sleep apnea); when accurate information on arrhythmia burden is desired (e.g., AF burden quantification).

These indications were supported by clinical respondents and evidence review.

Proposed medical necessity indications for MCOT

MCOT may be considered medically necessary when ANY of the following are met (staff recommendation):

MCOT medically necessary indications: (1) Evaluation of recurrent unexplained clinically significant presyncope, syncope, severe palpitations or dizziness when ALL of the following are met: symptoms are thought to be due to a cardiac arrhythmia as the most likely diagnosis; AND Holter monitor and/or external AEM has been nondiagnostic or contraindicated; AND there is documentation that real‑time monitoring is essential for patient safety and will lead to immediate clinical changes such as medication adjustment or emergent procedures; OR (2) Evaluation of cryptogenic stroke thought to be due to occult atrial fibrillation after nondiagnostic short‑term monitoring (consider extended monitoring ≥30 days or implantable loop recorder when indicated); OR (3) Monitoring arrhythmia status following an ablation procedure when real‑time detection will affect management; OR (4) Post‑procedure settings with new conduction abnormalities (e.g., post‑TAVR) where up to 30 days ambulatory monitoring with urgent alerts is indicated; OR (5) Detection of nocturnal arrhythmia (e.g., associated with sleep apnea) or quantification of AF burden when accurate long‑duration continuous data are needed.see node text

Logic preserves nested AND within first indication and OR between listed indications; staff recommendation updates prior investigational stance to conditional medical necessity.

The policy considers other uses of ambulatory event monitors (AEMs), including outpatient cardiac telemetry (MCOT) and mobile applications, investigational when they are applied to purposes without direct evidence that monitoring will change management. Examples specifically listed as investigational include monitoring asymptomatic individuals with risk factors for arrhythmia, monitoring the effectiveness of antiarrhythmic medications, and detection of myocardial ischemia by ST‑segment changes. This investigational stance reflects the absence of randomized trials demonstrating that such monitoring produces improved health outcomes or that real‑time transmission provides clinically meaningful incremental benefit over conventional AEMs in these situations.

A comprehensive, device‑level listing is beyond the scope of this policy. Newer wearable and patch‑based monitors, handheld ECGs, and other novel devices are described in the Background for informational purposes only; they are not enumerated exhaustively for coverage decisions. Device regulatory identifiers (FDA product codes) and example technologies are noted in the Background to aid clinicians in understanding available comparators, but coverage determinations are based on the clinical indication and evidence, not a prescriptive device catalogue.

No randomized controlled trials were identified that directly demonstrate clinical utility (improved patient health outcomes) from use of ambulatory monitoring in many of the proposed non‑diagnostic applications. The document explicitly states that direct evidence of clinical utility is lacking and that RCTs comparing management with and without the test are the preferred evidence for demonstrating outcome benefit. The policy also notes trials that were underpowered or of insufficient duration to evaluate clinical endpoints, limiting the ability to infer benefit where monitoring does not clearly change management.

The evidence does not support a consistent device‑specific superiority claim. Systematic reviews and comparative analyses of wearable devices versus Holter monitors or implantable loop recorders (ILRs) did not consistently show superior AF detection for wearables across populations; one review of studies comparing wearables with Holter or ILR monitoring did not demonstrate a clear difference in AF detection. Accordingly, the policy does not endorse a particular non‑implantable wearable device as superior for AF detection in all populations.

Randomized controlled trials demonstrating that monitoring‑guided management improves clinical outcomes (for example, reducing stroke or mortality) were not identified for many ambulatory monitoring strategies. The policy emphasizes that increased arrhythmia detection alone is insufficient to establish clinical utility; studies must show that detection leads to changes in treatment and that those changes improve patient‑centered outcomes. Absent such direct trial evidence, routine population‑level screening or routine use for indications that will not affect management remains unsupported.

The randomized trials and systematic reviews cited in the evidence review had important limitations relevant to interpreting clinical outcomes. Several RCTs were of insufficient duration or sample size to detect differences in clinical endpoints, some trials were stopped early, and many lacked racial and ethnic diversity. These methodological limitations reduce confidence that trial results adequately capture potential benefits or harms of monitoring strategies for clinical outcomes such as stroke.

Key clinical trials excluded patients with preexisting atrial fibrillation, implanted pacemakers/devices, or current anticoagulation, which constrains generalizability of findings to broader patient groups. These exclusions are highlighted because they limit applicability of trial results to patients who commonly present for ambulatory monitoring in clinical practice.

Large, well‑powered randomized trials with follow‑up sufficient to assess clinical endpoints (for example, LOOP, STROKESTOP and STROKESTOP II) have not consistently demonstrated improvements in primary outcomes such as combined stroke or systemic arterial embolism when monitoring strategies are compared with standard care. The inconsistency across these trials underscores uncertainty about the extent to which increased AF detection from long‑term monitoring translates into reduced clinical events at the population level.

Overall, no randomized controlled trials were found that provide direct evidence of clinical utility for many applications of ambulatory cardiac monitoring — in particular, there are no RCTs identified that compare patient management with and without mobile cardiac outpatient telemetry (MCOT) to show outcome benefit. Where randomized evidence exists it generally demonstrates higher detection rates but not consistent improvements in patient‑level clinical outcomes, and therefore claims of direct clinical utility remain unsupported by RCT evidence.

Provider Actions, Prior Authorization & Documentation

Prior Authorization

Prior authorization and CPT 93268 guidance

Prior authorization may be required by the member’s benefit plan; when plans require a single comprehensive code, use of CPT 93268 is recommended where appropriate to avoid unbundling of monitoring and analysis components.

In some contracts the monitoring and analysis components are performed by a monitoring service and may be unbundled if billed separately.
Inclusion of a code in the policy’s coding list does not guarantee coverage; follow member-specific benefit documentation.

Prior Authorization

Document clinical indication for authorization

When requesting prior authorization, document that the patient has signs or symptoms suggestive of arrhythmia (e.g., palpitations, dizziness, presyncope, syncope) and why extended or event monitoring is preferred over ECG or 24–48 hour Holter monitoring.

State that symptoms are infrequent (< every 48 hours) when applicable.
Explain why shorter-duration testing is insufficient for diagnostic yield.

Prior Authorization

Specify indication, device and monitoring plan

Prior authorization requests should state the clinical indication, the intended monitoring modality, the planned monitoring duration, and how the monitoring results will inform clinical management (for example, post‑AF ablation surveillance to guide anticoagulation).

Specify whether the request is for external patient‑activated AEM, continuous external AEM/patch, MCOT, or implantable monitor.
Describe the intended duration (days or months) and the expected impact on treatment decisions.

Prior Authorization

Specify device type and justify choice

Indicate the specific type of ambulatory monitoring requested (patient‑activated external event monitor, continuous external event monitor/patch, MCOT, or implantable loop recorder) and provide the clinical rationale comparing the requested device versus standard evaluation (ECG or 24–48 hour Holter).

Explain why a device with real‑time transmission is necessary if MCOT is requested.
If an ILR is requested, justify ILR versus extended external monitoring based on symptom frequency or expected diagnostic yield.

Prior Authorization

Document nondiagnostic shorter monitoring for cryptogenic stroke

For cryptogenic stroke evaluations requesting long‑term monitoring, prior authorization should document the nondiagnostic shorter monitoring (e.g., 24–48 hour Holter) and the rationale for extended monitoring because long‑term monitoring detects more AF and frequently leads to anticoagulation.

Include results of prior stroke workup (ECG, 24‑hour Holter, TEE, vascular imaging) when available.
State that detection of AF would change management (anticoagulation decision).

Documentation Required

ILR documentation: indication and monitoring plan

If an implantable loop recorder (ILR) is being requested, include indication details and a monitoring plan (device choice, expected monitoring duration, and the clinical threshold or management actions tied to detection).

Document prior nondiagnostic external monitoring when applicable.
If referencing trial thresholds (e.g., LOOP), note detection thresholds used in decision-making (trial AF thresholds were used to recommend anticoagulation).

Note

No single prior authorization rule specified in policy text

The policy text does not specify an explicit universal prior authorization rule or list of codes that automatically require authorization; follow member‑specific prior authorization processes and the coding guidance in the policy.

Absence of an explicit rule in the policy does not negate plan‑level requirements.
Check member-specific benefit documentation for authorization needs.

Prior Authorization

Justify need for long‑term (ILR) monitoring

When longer‑term monitoring is requested, justify why it is needed rather than an external monitor (e.g., symptoms are infrequent and prior external monitoring was nondiagnostic or the expected diagnostic yield of ILR justifies implantation).

Explain why ILR instead of extended external patch or ELR is clinically appropriate.
Cite symptom frequency (< every 48 hrs) or evidence predicting high likelihood of requiring long‑term monitoring.

Prior Authorization

Verify payer-specific prior authorization processes

The document does not prescribe payer-level prior authorization requirements; verify payer-specific prior authorization policies and processes when submitting requests.

Policy describes clinical criteria but does not replace plan prior authorization rules.
Use member-specific benefit documentation for final authorization determination.

Prior Authorization

When to consider MCOT (real‑time monitoring)

MCOT is considered when real‑time transmission and interpretation of ambulatory cardiac monitoring data are needed to evaluate individuals with signs or symptoms suggestive of arrhythmia and when immediate clinical action may be indicated.

Document why real‑time monitoring (MCOT) is essential for patient safety and immediate management.
Reserve MCOT for scenarios where emergent notification could change care (e.g., severe presyncope/syncope with suspected malignant arrhythmia).

Prior Authorization

Include nondiagnostic short‑term monitoring and real‑time need

Prior authorization submissions for MCOT should include evidence that Holter or external AEM was nondiagnostic or contraindicated, and a clear justification that real‑time monitoring is essential and will change immediate management.

Document prior Holter/AEM dates, duration, and results (nondiagnostic).
Explain how real‑time alerts would alter immediate clinical actions (medication changes, emergent procedures).

Documentation Required

Document medical necessity per CMS and payer rules

Medicare national coverage requires documentation of medical necessity for ambulatory cardiac monitors; providers should check payer‑specific prior authorization and medical necessity requirements when submitting requests.

Medicare NCD lists detection of symptomatic transient arrhythmias and determination of arrhythmic drug therapy as covered indications when medically necessary.
Use member‑specific benefit documentation and the policy’s coverage position when seeking authorization.

Billing Rule

Coding list does not guarantee coverage

The policy provides a coding list for reference, but inclusion of codes does not guarantee coverage; prior authorization may still be required per member‑specific plan terms.

If prior authorization is required, submit the relevant CPT/HCPCS/ICD‑10 codes (see policy coding section).
Coding alone does not establish medical necessity or guarantee payment.

Billing Rule

Include diagnosis and HCPCS/CPT codes plus prior monitoring evidence

When submitting an authorization request, ensure appropriate ICD‑10 diagnosis and HCPCS/CPT procedure codes are included and document prior nondiagnostic Holter/48‑hour telemetry when applicable.

Include diagnosis codes supporting arrhythmia suspicion (e.g., R00.2, R42, R55, I48.x) and HCPCS codes for implantable event recorders (E0616) when applicable.
Attach prior monitoring reports demonstrating nondiagnostic results.

Prior Authorization

MCOT/external telemetry: authorization may be required for listed CPTs

Prior authorization may be required for MCOT/external telemetry services billed with the listed CPT codes; coverage is limited to scenarios meeting the policy’s medical necessity criteria.

Codes referenced include 93241–93248, 93229, 93268, 93270–93272, and others (see policy coding table).
Ensure the clinical documentation maps to the code(s) and the policy indications.

Step Therapy

Preferred sequencing: prefer external monitors >48 hrs before ILR

External AEMs or continuous ambulatory monitors >48 hours are preferred alternatives to Holter monitoring; implantable monitors are considered after unsuccessful external monitoring or when long‑term monitoring is required.

Use Holter when symptoms are frequent enough (24–72 hours) and step up to extended external AEMs (>48 hours) when symptoms are less frequent.
Consider ILR when external monitors are nondiagnostic and symptoms are very infrequent.

Step Therapy

Try short‑duration monitoring (ECG/Holter) first when appropriate

Consider ECG and 24–48 hour Holter monitoring as the initial step before extended ambulatory event monitoring when clinically appropriate.

Holter monitoring is suitable when symptomatic events are anticipated within 24–72 hours.
Document prior short‑term monitoring results when requesting longer monitoring.

Step Therapy

Comparator expectation: document prior short‑term monitoring

Consider less‑extensive monitoring (ECG or 24–48 hour Holter) as the comparator prior to longer‑term devices; prior short‑term monitoring is expected in many indications.

Policy expects prior nondiagnostic Holter or 48‑hour telemetry before approving longer‑term MCOT in many cases.
If symptoms occur ≥ once every 48 hours, short‑term Holter or 48‑hour telemetry is preferred.

Step Therapy

Prior short‑term monitoring expected before longer monitoring

Consider prior shorter‑duration monitoring (ECG/Holter 24–72 hours) as the comparator before approving longer‑term ambulatory monitoring; the policy expects prior use of shorter monitoring to be nondiagnostic when longer monitoring is requested.

Include dates and results of prior Holter/48‑hour telemetry in the authorization.
If prior short‑term monitoring was diagnostic, extended monitoring may not meet policy criteria.

Step Therapy

Consider standard care first for asymptomatic screening

Use standard care (ECG, pulse palpation) first before prolonged ambulatory monitoring in asymptomatic screening contexts; routine screening without risk factors lacks evidence of improved outcomes.

Asymptomatic screening in unselected populations is unsupported by direct RCT evidence and generally not justified.
If screening is pursued, document risk factors and expected management changes from detection.

Step Therapy

Preferred diagnostic progression: external monitor → ILR when needed

Progression from shorter‑term external monitoring (e.g., Holter or event monitor) to longer monitoring or ILR is supported when longer monitoring is needed; initial external monitoring is generally preferred unless ILR is clearly indicated.

Document rationale if ILR is selected as initial strategy (high pretest probability of requiring long‑term monitoring).
Trials support diagnostic progression and higher detection with ILR when external monitoring is nondiagnostic.

Step Therapy

Choose monitor and duration per guideline recommendations

Select monitor type based on guideline recommendations: Holter for events within 24–72 hours; extended ambulatory ECG (15–30 days) when symptomatic events are not daily or are uncertain; continuous monitoring (1–14 days) to quantify burden.

Use AHA/ACC/HRS and ISHNE/HRS recommendations to guide device selection and duration.
Document why chosen duration aligns with symptom frequency and clinical goals.

Step Therapy

Prefer Holter/48‑hour telemetry when symptoms frequent

Consider short‑term Holter or 48‑hour telemetry before MCOT when symptoms are frequent (occurring ≥ once every 48 hours); MCOT is more appropriate for infrequent symptoms or when real‑time monitoring is essential.

If symptoms occur ≥ once every 48 hours, Holter or 48‑hour telemetry is preferred.
MCOT is for infrequent symptoms (< every 48 hours) with nondiagnostic short‑term monitoring and need for real‑time alerts.

Documentation Required

Document symptom frequency, prior nondiagnostic testing, and real‑time need

Authorization requests should document that symptoms are infrequent (< every 48 hours), prior Holter/AEM results were nondiagnostic, and that real‑time monitoring is essential for patient safety and will lead to immediate clinical changes when requesting MCOT.

Include explicit statement that symptoms are infrequent and prior monitoring results.
Explain the immediate clinical actions that would follow an emergent alert.

Documentation Required

Required clinical documentation for authorization

Required clinical documentation must include the indication (signs/symptoms of arrhythmia), duration and results of prior monitoring (ECG, 24–48 hour Holter), and explanation of how extended monitoring will change diagnosis or management.

Attach prior Holter/telemetry reports and indicate why these were nondiagnostic.
State the planned monitoring duration and how results will affect therapy (e.g., anticoagulation, antiarrhythmic drugs, procedures).

Documentation Required

Post‑ablation surveillance: document purpose and duration

When monitoring is requested for post‑ablation surveillance, documentation should include the indication (post‑AF ablation), monitoring purpose (detection of recurrent AF to inform anticoagulation), and expected monitoring duration.

Document time since ablation and clinical reasoning for anticoagulation decisions.
Include any prior monitoring performed and its results.

Documentation Required

Document cryptogenic stroke population and anticoagulation intent

For cryptogenic stroke/TIA monitoring requests, include that the patient is in the relevant population (history of cryptogenic stroke with negative standard workup) and that monitoring is intended to detect AF to inform anticoagulation decisions.

Provide details of the prior stroke workup (ECG, 24‑hour Holter, TEE, vascular imaging).
State the intended monitoring duration (policy notes ≥30 days or ILR may be considered).

Documentation Required

Cite trial evidence and trial characteristics in justification

When using trial evidence to justify monitoring (e.g., CRYSTAL AF, Gladstone, Kaura), document the trial characteristics cited (device type, monitoring duration, participant counts) and how those results support the requested strategy.

Cite specific RCTs and summarize detection rates and monitoring durations if relied upon in authorization rationale.
Include trial-derived thresholds or monitoring durations if used to support management choices.

Documentation Required

Provide evidence of diagnostic performance and clinical utility

Studies used to demonstrate clinical validity should report diagnostic performance (sensitivity, specificity, predictive values) or diagnostic yield; absence of such evidence or lack of clinical‑utility data (management impact) may lead to noncoverage.

Provide study-level evidence showing diagnostic performance if using literature to support a novel device or indication.
Clinical utility evidence should show how results changed management and outcomes.

Documentation Required

MCOT outpatient telemetry: required clinical documentation

Document that symptoms are most likely due to cardiac arrhythmia, include prior nondiagnostic Holter/external AEM when applicable, and state that real‑time monitoring is essential for patient safety and will lead to immediate clinical changes for outpatient cardiac telemetry requests.

For MCOT, explicitly state the immediate interventions expected following detection (e.g., medication change, emergent procedure).
Attach prior monitoring reports demonstrating nondiagnostic results.

Documentation Required

Medical necessity documentation required

Medical necessity must be documented to support coverage; acceptable indications include detection of symptomatic transient arrhythmias and determination of arrhythmic drug therapy (initiate, revise, discontinue).

Ensure documentation ties monitoring to a management decision that would reasonably follow detection.
Medicare NCD requires medical necessity documentation for ambulatory monitors.

Documentation Required

Use member‑specific benefits and policy when requesting coverage

Use member‑specific benefit plan documentation and this policy’s written coverage position when seeking coverage; coding alone does not ensure authorization or payment.

Check contract-specific definitions of medical necessity and least‑cost‑alternative provisions.
Provide member eligibility and benefit verification with the authorization request.

Documentation Required

State arrhythmia suspicion and prior nondiagnostic Holter/48‑hour telemetry

Document that symptoms are thought to be due to cardiac arrhythmia and that prior Holter monitor or 48‑hour telemetry was nondiagnostic or that symptoms occur less frequently than once every 48 hours when applicable.

Include monitored intervals and the reasons short‑term testing failed to capture events.
State symptom frequency explicitly (< every 48 hours) when that is the rationale for extended monitoring.

Documentation Required

Comprehensive required documentation for MCOT/extended monitoring

Required clinical documentation should show symptoms are thought to be due to cardiac arrhythmia, prior nondiagnostic Holter and/or external AEM when applicable, and that real‑time monitoring is essential for patient safety and will lead to immediate clinical changes.

Provide narrative justification linking monitoring to anticipated management changes.
Attach contemporaneous prior monitoring reports and summaries.

Billing Rule

Unbundling risk: prefer CPT 93268 when appropriate

Use CPT code 93268 when the bundled monitoring/analysis definition applies to reduce risk of payer consideration of unbundling; avoid billing separate component codes when the comprehensive code is appropriate.

Unbundled billing of components that should be reported under 93268 may lead to payer scrutiny.
Confirm whether the monitoring service performs the analysis and how billing should be reported under the member’s contract.

Documentation Required

Evidence reporting expectation for authorization

Provide study details demonstrating diagnostic performance (sensitivity, specificity, predictive values) when using published evidence to support coverage; lack of these data may result in denial or noncoverage.

If relying on literature to justify coverage, include metrics and how they apply to the member’s clinical scenario.
Absence of diagnostic‑performance reporting in supportive studies may weaken the authorization.

Denial Risk

Evidence limitations may impact coverage decisions

Lack of randomized trials demonstrating direct clinical‑utility (improved health outcomes) may result in denial where payers require direct outcome evidence to establish medical necessity.

Document how monitoring will change management even if RCT outcome data are limited.
Note that some indications (e.g., cryptogenic stroke) have RCT evidence of higher detection, but many MCOT uses lack RCTs showing outcome benefits.

Denial Risk

Denial risk if cryptogenic stroke workup or anticoagulation intent not documented

Monitoring after cryptogenic stroke is intended to inform anticoagulation decisions; lack of documentation demonstrating cryptogenic stroke workup or intent to guide anticoagulation may lead to denial.

Include diagnostic workup documentation (ECG, Holter, TEE, vascular imaging) to show cryptogenic classification.
State that detection of AF would lead to anticoagulation in this patient.

Denial Risk

Denial risk for MCOT when direct outcome evidence is lacking

No randomized controlled trials were identified that evaluated patient management with and without mobile cardiac monitoring; absence of direct outcome evidence for some MCOT uses may lead to denial if medical necessity for real‑time monitoring is not clearly documented.

Provide explicit clinical justification for real‑time monitoring and how it will change immediate management.
Observational data alone may be insufficient in some payer determinations.

Denial Risk

Risk of denial if standard‑care comparator not addressed

Denial risk could arise if monitoring is provided instead of standard care without documentation; include explanation why standard care (ECG or pulse check, short Holter) is inadequate or contraindicated.

If foregoing standard care, document why it would not have been diagnostic or safe.
Attach prior standard‑care test results showing nondiagnostic findings.

Documentation Required

Evidence requirements for diagnostic validity

Studies used to demonstrate clinical validity should report diagnostic performance (sensitivity, specificity, predictive values) or diagnostic yield; absence of these details could risk noncoverage determinations for investigational tests.

When submitting supportive studies, include the performance metrics requested by the policy.
For devices with limited published performance metrics, clarify how detection capability was determined.

Denial Risk

Evidence gap may lead to denial for MCOT uses

Lack of randomized trials evaluating management with and without MCOT may trigger denial if payers require randomized evidence that real‑time monitoring improves outcomes.

Be prepared to provide observational evidence and a clinical rationale linking real‑time detection to improved safety or management.
Highlight scenarios where immediate intervention clearly prevents harm.

Denial Risk

Denial risk if medical necessity not documented

Claims for ambulatory cardiac monitors may be denied if documentation of medical necessity is not provided, consistent with Medicare national coverage guidance.

Ensure medical necessity documentation accompanies claims and prior authorization requests.
Medicare NCD requires documentation that monitoring will inform treatment decisions.

Billing Rule

Coding list inclusion does not assure coverage

Inclusion of a code in the policy’s coding tables does not guarantee coverage; all determinations remain subject to member‑specific benefit plan provisions and contract terms.

Do not rely solely on the presence of a CPT/HCPCS code to establish coverage.
Confirm member eligibility and plan coverage terms prior to ordering or billing.

Denial Risk

Avoid monitoring for non‑cardiac symptom etiologies or when short‑term monitoring diagnostic

Use ambulatory monitoring only for symptoms likely due to cardiac arrhythmia; monitoring for symptoms unlikely to be cardiac or when prior Holter/48‑hour telemetry was diagnostic is unlikely to meet the policy criteria.

If symptoms are unlikely cardiac in origin, provide rationale for monitoring and expected management changes from detection.
If prior short‑term monitoring was diagnostic, extended monitoring may not be warranted.

Prior Authorization

Coverage contingent on meeting MCOT criteria

Coverage for MCOT is contingent on meeting the policy criteria; previously investigational uses for infrequent symptoms now require documentation meeting the listed criteria (nondiagnostic short‑term monitoring, real‑time need, etc.).

Ensure the request maps to one of the policy’s enumerated indications for MCOT.
Document prior testing and the necessity for real‑time surveillance.

Note

Coding & Billing

Billing guidance / recommended CPTCPT

93268

Monitoring and analysis code referenced to avoid unbundling (documented in policy guidance)

FDA product codes (informational)mixed

DSH	FDA product code listed
DXH	FDA product code listed
DQK	FDA product code listed
DSI	FDA product code listed
MXD	FDA product code listed
MHX	FDA product code listed

FDA product codes mentionedmixed

DSH	FDA product code listed in policy
DXH	FDA product code listed in policy
DQK	FDA product code listed in policy
DSI	FDA product code listed in policy
MXD	FDA product code listed in policy
MHX	FDA product code listed in policy

Devices and comparators discussedmixed

No codes listed

Covered/Referenced device types (no billing codes provided in this section)mixed

No codes listed

Referenced procedure and supply codesmixed

93241	External electrocardiographic recording for more than 48 hours up to 7 days by continuous rhythm recording and storage; includes recording, scanning.
93242	by continuous rhythm recording and storage; includes recording, scanning analysis with report, review and interpretation; recording (includes connection and initial recording).
93243	; recording (includes connection and initial recording); scanning analysis with report.
93244	; scanning analysis with report; review and interpretation.
93245	External electrocardiographic recording for more than 7 days up to 15 days by continuous rhythm recording and storage; includes recording, scanning analysis with report, review and interpretation.
93246	analysis with report, review and interpretation; recording (includes connection and initial recording).
93247	; recording (includes connection and initial recording); scanning analysis with report.
93248	; scanning analysis with report; review and interpretation.
93228	Removal, subcutaneous cardiac rhythm monitor
33285	Insertion, subcutaneous cardiac rhythm monitor, including programming.

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Referenced diagnosis codesICD-10

I44.0-I44.7	Atrioventricular and left bundle-branch block code range
I45.0-I45.9	Other conduction disorders code range
I47.0-I47.9	Paroxysmal tachycardia code range
I48.0-I48.1	Atrial fibrillation and flutter code range
I49.01-I49.9	Other cardiac arrhythmias code range
I63.9	Cerebral infarction, unspecified (Stroke NOS)
R00.2	Palpitations
R42	Dizziness and giddiness
R55	Syncope and collapse

ICD-10-PCS (inpatient) exampleICD-10-PCS

4A12X45

ICD-10-PCS example: Measurement and monitoring, physiological systems, monitoring, cardiac...

HCPCS codesHCPCS

C1764

HCPCS code listed in document

HCPCS implantable event recorderHCPCS

E0616

Event recorder, cardiac (implantable); implantable cardiac event recorder with memory, activator, and programmer

ICD-10-PCSICD-10

4A12X45

ICD-10-PCS code (measurement and monitoring, physiological systems, cardiac)

ICD-10 diagnosis code ranges and specific codesICD-10

I44.0-I44.7	Atrioventricular and left bundle-branch block code range
I45.0-I45.9	Other conduction disorders code range
I47.0-I47.9	Paroxysmal tachycardia code range
I48.0-I48.1	Atrial fibrillation and flutter code range
I49.01-I49.9	Other cardiac arrhythmias code range
R00.2	Palpitations
R42	Dizziness and giddiness
R55	Syncope and collapse
I63.9	Cerebral infarction, unspecified (stroke NOS)

Ambulatory/micro telemetry CPT codesCPT

93241	External electrocardiographic recording for more than 48 hours up to 7 days by continuous rhythm recording and storage; includes recording, scanning analysis with report, review and interpretation.
93242	Recording (includes connection and initial recording).
93243	Scanning analysis with report.
93244	External electrocardiographic recording for more than 7 days up to 15 days by continuous rhythm recording and storage; includes recording, scanning analysis with report, review and interpretation.
93245	Review and interpretation.
93246	Continuous rhythm recording and storage; includes recording, scanning analysis with report, review and interpretation.
93247	Recording (includes connection and initial recording).
93248	Scanning analysis with report; review and interpretation.
93285	Programming device evaluation (in person) with iterative adjustment of the implantable device to test function and select optimal permanent programmed values with analysis, review and report.
33285	Insertion, subcutaneous cardiac rhythm monitor, including programming (listed alongside 93285 in the document).

Symptom frequency threshold — infrequent symptoms

Symptom frequency thresholdInfrequent symptoms defined as occurring less frequently than every 48 hours

Use contextApplies when symptoms (palpitations, dizziness, presyncope, or syncope) are not captured by short-term monitoring and longer monitoring is needed

Prior monitoring expectationPolicy expects prior nondiagnostic Holter or 48-hour telemetry when symptoms are frequent enough; infrequent symptoms (< every 48 hours) justify extended monitoring

Holter monitoring duration

Holter monitoring durationHolter monitors are capable of recording cardiac electrical activity continuously for 24 to 72 hours

Typical channelsTraditionally most Holter monitors have 3 channels; some currently available have up to 12 channels

Use-caseAppropriate when symptoms are frequent enough to be detected within 24–72 hours (eg, daily symptoms)

ILR AF detection threshold

ILR AF detection threshold (trial-defined)Atrial fibrillation episode lasting ≥6 minutes was used as the detection threshold prompting contact and recommended anticoagulation in the LOOP trial

LOOP trial monitoring contextLOOP used implantable loop recorders with automated remote transmissions and daily physician review; median monitoring ~39.3 months

Clinical implicationDetection threshold (≥6 minutes) was protocol-specified for outreach and anticoagulation recommendation in the referenced trial

Note

Definitions & Device Types

Holter monitor

DefinitionHolter monitor: a continuously worn recorder that captures cardiac electrical activity continuously for 24 to 72 hours

Recording characteristicsTypically records continuously and may have 3 channels (commonly) up to 12 channels in some devices

Appropriate indicationUsed when a short period (24–48 hours) of comprehensive rhythm assessment is needed, e.g., suspected arrhythmias occurring daily

Mobile cardiac outpatient telemetry (MCOT)

DefinitionMobile cardiac outpatient telemetry (MCOT): continuously recording or auto-triggered devices that transmit data to a central recording station with real-time monitoring and analysis

ExamplesNamed systems include CardioNet MCOT and LifeStar Mobile Cardiac Telemetry; some patch-based systems (eg, Zio AT) have similar functionality

Use-case in policyConsidered medically necessary when real-time monitoring is essential for patient safety and prior short-term monitoring is nondiagnostic

External memory (loop) recorder

DefinitionExternal memory (loop) recorder: devices worn continuously that store ECG in a refreshed loop memory and record pre-event and post-event segments when patient-activated or auto-triggered

Activation modesCan be patient-activated when symptoms occur or auto-triggered by algorithms detecting arrhythmia-like changes

Typical recording segmentsRecords preceding (~30–90 seconds) and subsequent (~60 seconds) ECG around the event in loop memory devices

Implantable loop recorder (ILR/ICM)

DefinitionImplantable loop recorder (ILR/ICM): a device implanted subcutaneously in the precordial area for long-term continuous rhythm monitoring

Monitoring durationProvides months-to-years of continuous ECG monitoring (eg, median monitoring 39.3 months in LOOP trial)

Triggering and useCan be patient- or auto-triggered; used for very infrequent symptoms or long-term AF detection after cryptogenic stroke or post-ablation surveillance

Patient-activated and continuous event monitoring — definitions

Patient-activated event monitoringDevices applied by the patient when symptoms develop to capture ECG at the time of symptoms

Continuous event monitoringDevices worn continuously that record activity continuously and can store data for periods longer than Holter monitors; may auto-trigger when arrhythmia detected

Intended useSelection depends on symptom frequency and clinical need to capture spontaneous or infrequent events

Clinical indications — Arrhythmia-related symptoms

Core arrhythmia‑related symptomsDizziness, syncope/near syncope, and palpitations

Clinical relevanceDiagnosis of certain arrhythmias has direct management implications (eg, anticoagulation for AF, ICD for lethal arrhythmias)

Policy contextThese symptoms are the primary indications considered for long-term ambulatory monitoring in the policy

External loop recorder (ELR)

DefinitionExternal loop recorder (ELR): a wearable auto-triggered or patient-activated device that records cardiac rhythm for extended periods (eg, ~30 days) compared with a 24–72 hour Holter

Comparative yieldUsed in trials (eg, Gladstone) where 30-day ELR had higher AF detection vs 24-hour Holter

ActivationMay be auto-triggered or patient-activated depending on device model

Implantable loop recorder (ILR)

DefinitionImplantable loop recorder (ILR): a subcutaneously implanted device providing continuous long-term rhythm monitoring (also called insertable cardiac monitor, ICM)

Evidence baseRandomized trials (eg, CRYSTAL AF, LOOP) demonstrate higher detection rates with ILR compared with short-term monitors

IndicationsAppropriate for very infrequent symptoms or for prolonged AF surveillance after cryptogenic stroke or ablation

Patient-activated and continuous event monitoring — definitions

Patient‑activated devicesApplied by the patient at symptom onset to record ECG around the event

Continuous/auto-triggered devicesWorn continuously with algorithms to auto-detect and store events; provide higher likelihood of capturing asymptomatic events

Selection noteChoice between patient-activated and continuous devices depends on symptom frequency and need for uninterrupted surveillance

Patch ECG

Patch ECGLong-term (≥14 days) adhesive patch monitor providing prolonged ambulatory ECG recording with good patient acceptance but limited spatial electrode distribution

Advantages/limitationsGood patient acceptance and prolonged recording; limited electrode spacing may reduce localization and variable ECG quality in some patients

Use-caseUsed for extended noninvasive monitoring (eg, Zio XT in trials) as alternative to Holter for longer-duration assessment

MCOT — multilead continuous streaming monitor

MCOT — multilead continuous streamingMCOT is a multilead continuous streaming monitor with real-time autodetection and auto-transmission capability, offering higher sensitivity/specificity for arrhythmia detection

TradeoffsMay require frequent electrode changes and have reduced long-term patient acceptance compared with patch monitors

Intended useSuitable when near real-time detection and urgent alerting are clinically important

External electrocardiographic recording codes (93241-93248)

CPT range describedExternal electrocardiographic recording CPT codes 93241–93248 describe continuous rhythm recording and storage services with varying durations, analysis, and reporting components

Services includedCodes encompass recording, scanning/analysis with report, review and interpretation, and duration-based distinctions (eg >48 hours up to 7 days, >7 up to 15 days)

Reference for billingPolicy lists these CPT descriptors for external continuous recording and storage services

Background & Evidence Context

Ambulatory cardiac monitoring is used when arrhythmias are suspected but are not captured on a standard 12‑lead ECG. Short‑term Holter monitors record continuously for 24–72 hours and are appropriate when symptoms are frequent. Longer‑term external event monitors, patch monitors, implantable loop recorders (ILRs), and mobile cardiac outpatient telemetry (MCOT) are alternatives when symptoms are infrequent or prolonged surveillance is needed; they increase diagnostic yield beyond short‑term monitoring and are selected based on symptom frequency, expected diagnostic duration, and clinical indication.

Evidence-based coverage considerations — monitoring increases AF detection but impact on clinical outcomes is mixed

Summary of trial evidence: Randomized trials and systematic reviews show increased AF detection with ambulatory monitoring versus usual care; however, adequately powered trials assessing clinical outcomes (stroke/systemic embolism) have produced mixed results, especially when trials are limited to external noninvasive monitoring methods.

Policy cites LOOP, STROKESTOP, and other RCTs and meta‑analyses.

Clinical studies relevant to coverage emphasize improved arrhythmia detection and reduced time to diagnosis with extended monitoring. Randomized evidence (Rothman et al.) showed MCOT detected more diagnoses and yielded shorter median time to diagnosis compared with a looping event monitor in a 30‑day trial, while large retrospective cohorts report higher detection rates with MCOT than with some looping devices and that a minority of detected events are potentially emergent. These detection and time‑to‑diagnosis findings inform the policy’s rationale but do not by themselves establish outcome benefit.

Evidence summaries indicate that ILRs offer higher diagnostic yield than external monitors for infrequent symptoms and that longer monitoring increases AF detection compared with 24–48 hour Holter monitoring. For MCOT, evidence shows at least comparable arrhythmia detection to ambulatory event monitors and offers real‑time transmission capability; however, evidence that real‑time monitoring leads to improved clinical outcomes is lacking. The policy’s coverage positions distinguish device types and clinical scenarios, endorsing ILR or extended external monitoring where detection is likely to change management and supporting conditional use of MCOT when real‑time monitoring is essential for safety.

The coverage stance is nuanced by device type and clinical scenario. External and implantable ambulatory event monitors are supported when extended monitoring would alter therapy (for example, to guide anticoagulation after AF detection or to diagnose arrhythmias leading to pacemaker/ablation decisions). MCOT is recognized as capable of real‑time surveillance and may be reasonable in selected patients when documentation shows that real‑time monitoring is essential for patient safety and will lead to immediate clinical changes. The updated staff recommendation replaces a prior investigational stance for outpatient cardiac telemetry in specific, documented clinical situations.

Revision History

2026-06-01policy_revisionLatest

Staff revised the policy statement to allow MCOT (outpatient cardiac telemetry) to be considered medically necessary in specified situations for individuals with infrequent symptoms, replacing the prior investigational stance.

Previous policy language considered outpatient cardiac telemetry investigational for individuals with infrequent symptoms (< every 48 hours). The current revision (staff recommendation) changes that position to allow MCOT as medically necessary in selected scenarios when specified criteria are documented (for example, nondiagnostic Holter/external AEM and need for real‑time monitoring to affect immediate management). This reflects the policy change summarized in the reconciliation table.

2021-05-27policy_replacement

Blue Cross of Idaho replaced and adopted an updated policy, effective 2021-05-27 (literature review through March 25, 2021); policy statements unchanged.

2022-05-26policy_replacement

Blue Cross of Idaho replaced and adopted an updated policy, effective 2022-05-26 with literature review through April 8, 2022; policy statements unchanged.

2023-05-25policy_replacement

Blue Cross of Idaho replaced and adopted an updated policy, effective 2023-05-25 with literature review through April 11, 2023; policy statements unchanged.

2024-05-30policy_replacement

Blue Cross of Idaho replaced and adopted an updated policy, effective 2024-05-30 with literature review through April 9, 2024; policy statements unchanged.

2025-10-30policy_replacement

Blue Cross of Idaho replaced and adopted an updated policy, effective 2025-10-30 with literature review through August 29, 2025; references updated.

2026-02-26policy_replacement

Blue Cross of Idaho adopted revisions with literature review through December 2, 2025; policy updated and adopted for effective date 2026-06-01 (staff recommendation to change MCOT stance included in reconciliation).

2026-06-01policy_effective_dateLatest

Revised policy became effective on 2026-06-01, implementing the staff recommendation that allows MCOT as medically necessary in specified situations.