Zio XT for ambulatory heart rhythm monitoring: a cost-benefit analysis
Authors: Fawzy A M , Edmonds J , Shannon A , Wright D J 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Zio XT is a recent technology that has enabled automated heart rhythm analysis using an artificial intelligence-based algorithm. It can be fitted by patients and record the heart rhythm for 14 days, offering potential convenience, accuracy and efficiency compared to Holter monitors. However, data on its cost-effectiveness and impact on healthcare resources is lacking.

Purpose
We performed a cost-benefit analysis of Zio XT for electrocardiogram (ECG) monitoring, using Holter monitors as the standard.

Methods
200 patients that had Holters and 204 that had Zio XT at our centre were evaluated. Primary outcomes included impact of Zio on the number of outpatient appointments (OPAs) per year and impact on the cardiac physiologist (CP) workforce, depicted by whole time equivalent (WTE), calculated as the number of hours per year spent on monitor fitting or rhythm analysis ÷ total working hours per year. Secondary outcome was the impact on implantable loop recorders (ILR) insertions per year and the resultant effect on cost and time. Data from the 200 Holter and 204 Zio cases was extrapolated to model outcomes for 1 year, assuming 2000 patients undergo ECG monitoring per year (based on annual figures for our centre).

Results
96% of Holter patients had OPAs for monitor fitting and 87% for follow-up. Corresponding figures for Zio patients were 0.5% and 70.1% respectively. Extrapolating this to our annual cohort estimated a net reduction of 1910 OPAs for monitor fitting and 338 for follow-up, saving a total of 2248 OPAs/year with Zio use. 65%, 12% and 23% of Holter patients underwent 24 hour (hr)-, 48hr- and 7 day-tapes respectively. Using a projected time of 20 minutes to fit a device and 30, 45 and 60 minutes to analyse a 24hr-, 48hr- and 7 day-tape respectively, we derived a total WTE of 0.41 for monitor fitting and WTE of 0.79 for rhythm analysis (Table 1), i.e. 41% of a band 4 CP’s time is spent on device fitting and 79% of a band 6 CP’s time is spent on analysis. For Zio, the WTE for device fitting was 0.002 and that for analysis was 0, suggesting that a WTE of 0.41 can be saved on monitor fitting and 0.788 on rhythm analysis. Using our data, we extrapolated that 10 patients in the Zio group and 60 in the Holter group would require ILRs in a year. Assuming an ILR insertion takes 15 minutes and removal takes 30 minutes, we estimated that Zio use could save 38 hrs of a CP’s time/year. Further, a saving of £90,000 was projected from the 50 ILR insertions that could be avoided (using a cost of £1800 per ILR insertion).

Conclusion
Our findings indicate that Zio XT is associated with a significant reduction in OPAs, ILR insertions and time spent on monitor fitting and rhythm analysis, and thus, is potentially cost- and time-saving. This could reduce outpatient waiting lists and liberate valuable physiologist time that can be redirected towards other services. Further reduction in OPAs may be observed as we emerge from the Zio learning path.