Safety Profile of a Miniaturized Insertable Cardiac Monitor: Results from Two Prospective Trials

Background: Insertable cardiac monitors (ICMs) are used to continuously monitor the patient's electrocardiogram. In response to patient activation or based on automated device algorithms, arrhythmia episodes are stored and automatically transmitted daily to the clinician. Thus, ICMs can be used to diagnose arrhythmias in at-risk patients and in those with symptoms potentially attributable to arrhythmias. The ICM described in this report has undergone a dramatic change in size and method of insertion.

Methods: To evaluate the safety profile of the ICM procedure, we analyzed procedure-related adverse events (AEs) from two separate trials: A controlled, nonrandomized multicenter study (Reveal LINQ(TM) Usability study) and a multicenter registry (Reveal LINQ(TM) Registry) evaluating real-world experience. For the Registry we reported all procedure-related AEs upon occurrence, whereas for the Usability study, we reported events occurring during the first month of follow-up.

Results: The Usability study enrolled 151 patients (age 56.6 ± 12.1 years; male 67%) at 16 centers; during follow-up, an infection was observed in 1.3% patients and a procedure-related serious AE (SAE) in 0.7% patients. The Registry enrolled 122 patients (age 61.0 ± 17.8 years; male 47%) at seven centers; during follow-up, an infection was observed in 1.6% patients and a procedure-related SAE in 1.6% patients.

Conclusions: The cumulative experience from a controlled clinical trial and a "real-world" registry demonstrate that the new ICM can be inserted with very low incidence of AEs.