This document addresses ambulatory cardiac event monitors. Specifically:

• External ambulatory event monitors with real-time transmission capability (also referred to as real-time remote heart monitors or mobile outpatient cardiac telemetry). The external mobile outpatient cardiac telemetry monitors have an additional feature that uses cellular telephone communications technology to communicate heart rhythms in real-time to a central monitoring station.
• Implantable ambulatory event monitors.

This document does not address interrogation of implantable ambulatory event monitors. Device interrogation refers to checking on the status of batteries and leads in monitoring devices which are implanted inside the body.

Note: Please see the following related documents for additional information:

• CG-MED-40 External Ambulatory Cardiac Monitors

Clinical Indications

I. Mobile Cardiac Telemetry

Medically Necessary:

The use of mobile cardiac telemetry is considered medically necessary for individuals who meet criterion A and criterion B below:

1. The individual has one of the following conditions:
   1. Individuals who have symptoms suggestive of cardiac arrhythmias less frequently than once every 48 hours; or
   2. For the detection of suspected paroxysmal atrial fibrillation following cryptogenic stroke when the monitoring is intended to guide medical management with anticoagulants; and
2. The individual has had a non-diagnostic external ambulatory cardiac event monitoring trial of not less than 14 continuous days.

Not Medically Necessary:

The use of mobile cardiac telemetry is considered not medically necessary when the above criteria have not been met, and for all other indications.

II. Implantable Ambulatory Event Monitor

Medically Necessary:

The use of implantable ambulatory event monitors is considered medically necessary for individuals who have a history of cryptogenic stroke and had a previous non-diagnostic trial of external ambulatory event monitoring.

The use of implantable ambulatory event monitors is considered medically necessary for individuals with recurrent syncope who have all of the following:

1. Age greater than or equal to 40; and
2. History of multiple (three or more) syncopal episodes of undetermined etiology in the past 2 years; and
3. Previous diagnostic evaluation, including history, physical exam, electrocardiogram, orthostatic blood pressure measurements and echocardiogram, has not yielded a diagnosis; and
4. Previous non-diagnostic trial of external ambulatory cardiac event monitoring of not less than 14 continuous days.

Replacement of implantable ambulatory event monitors is considered medically necessary when the device is not operating and criteria for initial insertion continue to be met.

Not Medically Necessary:

The use of implantable ambulatory event monitors is considered not medically necessary when the above criteria have not been met, and for all other indications.