Comparative Clinical Outcomes Across Ambulatory Cardiac Monitoring Modalities

Comparative effectiveness data across ambulatory cardiac monitoring (ACM) modalities are limited.

To confirm and extend comparative findings across ACM modalities and vendors in commercially insured and Medicare Advantage beneficiaries without prior arrhythmia.

Retrospective study using Optum Research Database. Adults ≥ 18 years with first ACM use between January 1, 2017 and June 30, 2022 were categorized as long-term continuous monitors (LTCM), Holter, external ambulatory event monitors (AEM), or mobile cardiac telemetry (MCT). Outcomes were arrhythmia diagnosis (90 days), repeat monitoring (180 days), cardiovascular events, hospitalization, emergency department [ED] visits, and costs (365 days). Inverse probability of treatment weighting used a specific LTCM (iRhythm Technologies, San Francisco, CA) as reference.

Among 352,782 patients (mean age 62.0 ± 17.1 years; 61% female), 25% received LTCM, 37% Holter, 20% AEM, and 18% MCT. Among LTCM users, 58% received iRhythm LTCM. Compared with this LTCM, Holter, MCT, and other LTCM had lower odds of arrhythmia diagnosis (IPTW-weighted ORs 0.50-0.95; p < 0.01); AEM did not differ. Repeat monitoring was higher for other LTCM, AEM, and Holter (IPTW-weighted ORs 1.99-2.77; p < 0.001); MCT did not differ. All other modalities had higher IPTW-weighted odds of cardiovascular events (ORs 1.10-1.66; p < 0.001), hospitalization (ORs 1.12-2.04; p < 0.001), ED visits (ORs 1.09-2.08; p < 0.001), and costs (IPTW-weighted cost ratios 1.03-1.28; p < 0.01).

Outcomes differed across ACM modalities and vendors, confirming observations in other payer populations. A specific LTCM was associated with higher claims-based arrhythmia yield and lower repeat monitoring than most alternatives, and with lower hospitalization, health care utilization, and costs.