Real-World Incidence of Pacemaker and Defibrillator Implantation Following Diagnostic Monitoring With an Insertable Cardiac Monitor.

Insertable cardiac monitors (ICM) are used in patients with suspected or known cardiac arrhythmias; the resulting diagnosis can lead to therapeutic interventions such as a pacemaker (PPM) or defibrillator (ICD) implant. We investigated the incidence of these implants in a large, real-world, cohort of ICM patients. The Optum© EHR de-identified database was used to identify patients with cardiovascular diseases, an ICM implant, ≥180 days of follow-up before and after ICM implant, and no previous history of a PPM or ICD. The Kaplan-Meier (KM) incidence estimates for device implants following an ICM implant were determined. A total of 19,173 patients with an ICM implant were identified. During a mean follow-up of 40 months, either a PPM or ICD was implanted in 21% of patients. A device was implanted in 25% of patients with history of syncope compared with 15% in patients with another indication for ICM implant (p <0.001). There was a significantly greater number of PPM implants following an ICM in patients with history of syncope compared with another indication for ICM implant (23% vs 13% p <0.001); in contrast, there was no difference in ICD implants between the 2 groups (3% in both groups, p = 0.84). In conclusion, a PPM or ICD was ultimately implanted in 21% of ICM patients. Pacemaker implant rates varied significantly with indication for ICM implant, whereas ICD implants rates were similar. In particular, patients with history of syncope had the greatest likelihood of needing a PPM during follow-up.