Assessment of Variation in Ambulatory Cardiac Monitoring Among Commercially Insured Patients
Real-World Evidence Using a Large Commercial Claims Database
The Assessment of Variation in AmbuLatory Cardiac MONitoring (AVALON) study—the largest real-world study of ambulatory cardiac monitoring (ACM) in a commercial setting—found that the Zio® long-term continuous monitoring (LTCM) service was associated with the highest likelihood of new arrhythmia diagnosis and the lowest likelihood of having a cardiovascular event at 1 year.1-5,7
Zio LTCM service was associated with1-4,7:
Study Design1,7
Conducted using one of the largest commercial claims databases.
Analyzed 428,707 commercially insured, diagnostic-naive adults (≥18 years).
Patients were monitored with one of three ACM types: LTCM, Holter monitors, or event monitors.
Key Findings
The AVALON study revealed key information about the diagnostic proficiency and clinical benefits associated with the Zio LTCM service compared to Holter, event, and non-iRhythm LTCM1-4,7:
ZIO LTCM SERVICE WAS MORE LIKELY TO DIAGNOSE ARRHYTHMIAS WITHIN 90 DAYS2,3
Time to diagnosis was also shorter for Zio LTCM (9 days) compared to Holter (12 days), non-iRhythm LTCM (21 days), and event (30 days).3,7
ZIO LTCM SERVICE SHOWED LOWER ODDS OF RETESTING WITHIN 180 DAYS
ZIO LTCM SERVICE HAD A LOWEST LIKELIHOOD OF CV EVENTS AT 1 YEAR8
The Zio LTCM service was also associated with reduced healthcare resource utilization compared to Holter, event, and non-iRhythm LTCM services.1,4,7
HEALTHCARE RESOURCE UTILIZATION
These differences persisted after adjustment for patient demographics, comorbidities, and socioeconomic factors.
Over 700,000 patients across Medicare and commercial populations were evaluated through the CAMELOT9 and AVALON1 studies. CAMELOT was the first large-scale real-world study to demonstrate variation in outcomes by ACM type in a Medicare population. AVALON expanded on CAMELOT by including a commercial audience spanning the social and economic spectrum. Both CAMELOT and AVALON drew the same conclusions: long-term continuous monitoring, especially with the Zio LTCM service, enhanced diagnostic capability, reduced healthcare resource utilization, and improved patient outcomes.1-4,6,9-11
From Medicare beneficiaries to commercially insured adults across the social and economic spectrum, these landmark real-world analyses provide robust evidence that monitoring strategy matters and that LTCM is associated with differences that extend well beyond detection alone.
Keep reading
- The Zio™ service is a long-term continuous ambulatory cardiac monitoring service. It consists of the Zio™ device that collects beat-to-beat ECG data and can be worn for up to 14 days; the Zio™ ECG Utilization Service (ZEUS) System deep learned algorithm which detects arrhythmias. The data is reviewed and curated by a team of Qualified ECG Specialists (QES) to provide the final patient report
- For indications for use, warnings & contraindications visit our EU or UK website for more information
- For further regulatory information visit our website for more information
- iRhythm, Zio, Zio XT, MyZio and ZioSuite are trademarks of iRhythm Technologies, Inc.© 2026 All rights reserved.
- Zio™ monitor and ZEUS are CE-marked (CE2797) and currently available in Austria, Netherlands, Spain & Switzerland.
- Zio™ XT and ZEUS are UKCA-marked (UKCA0086) and currently available in the UK.
- Based on US Data
The Zio™ service is a long-term continuous ambulatory cardiac monitoring service. It consists of the Zio™ monitor that collects beat-to-beat ECG data and can be worn for up to 14 days; the Zio™ ECG Utilization Service (ZEUS) System deep learned algorithm, which detects arrhythmias. The data is reviewed and curated by a team of Qualified ECG Specialists (QES) to provide the final patient report.
For indications for use, warnings & contraindications, visit here.
iRhythm, Zio, Zio monitor and ZioSuite are trademarks of iRhythm Technologies, Inc. ©2026 All rights reserved.
Zio™ monitor and ZEUS are CE-marked (CE2797).
Zio monitor, ZEUS and Zio service are currently available in Austria, Netherlands, Spain & Switzerland.
For further regulatory information visit here.
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