Patch ambulatory rhythm monitoring in children: a cost-effectiveness analysis

Purpose: The Zio (iRhythm Technologies) is a small and adhesive monitor that can be worn for up to 2 weeks to evaluate heart rhythm in an ambulatory setting, with an option for patient triggering to record symptoms. As compared to traditional Holter or event monitors, this novel technology may have a higher diagnostic yield, but has a higher per-unit cost. We conducted a cost-effectiveness analysis in detecting findings affecting clinical management by comparing Zio monitor testing alone to theoretical models representing the Holter (24- and 48-hour), event monitor, or a combination of these modalities. Methods: This study presents a cost-effectiveness analysis using data collected on 373 Zio studies performed on patients 0-18 years in a pediatric cardiology clinic. The results were analyzed and compared to 5 theoretical models: Model A: 24-hour Holter (using Zio findings from the first 24 hours); Model B: 48-hour Holter; Model C: event monitor (only using Zio findings that were patient-triggered); Model D: 24-hour Holter + event (using Zio findings from the first 24 hours plus any subsequent patient-triggered findings); and Model E: 48-hour Holter + event. Effectiveness was measured by the percentage of studies that changed clinical management, which included escalation of care (e.g., new medication, intervention, or increased frequency of follow up recommended) or discharge from follow up. Costs were assigned using 2018 CMS reimbursement rates, and comparison was made using the incremental cost effectiveness ratio (ICER), which measures the difference in cost divided by the difference in effectiveness. Results: Using Zio testing alone identified findings that led to management change in 55.8% of studies; Model E (48 hour Holter + event) represents the next most effective at 45.0%, while Model A (24 hour Holter) represents the least effective at 3.2% (see Figure 1). Total costs and effects are presented in Table 1. The cost per management change using Zio testing is $645.58, which is less than Models A or B, but more than Models C-E. The ICER for Zio testing that led to management change ranges from $508.35 over Model A (95% CI = $460.22 - $572.37), to $1,692.37 over Model E (95% CI = $880.44 - $29,430.45). Conclusion: Zio testing is more cost-effective when compared to models of isolated Holter or event monitoring, but less so when compared to models combining these modalities. Zio testing is least cost-effective compared to Model E (combined 48-hour Hol