New implantable cardiac monitor with three-lead ECG and active noise detection.

BACKGROUND

A new implantable cardiac monitor (BioMonitor, Biotronik) with a continuous remote monitoring option was prospectively implanted in patients with suspected arrhythmias or for therapy control after atrial fibrillation (AF) ablation. A three-lead ECG detection was intended to make the implantation more independent of the implantation site and the electrical heart axis. Because noise is a frequent problem in implantable cardiac monitors, an active noise detection algorithm was implemented. The aim of the trial was to evaluate the clinical performance of the device.

METHODS

The device performance was evaluated in a prospective nonrandomized multicenter study with a follow-up of 12 months. Study endpoints were device-related serious adverse events at 3 months, appropriate QRS detection in direct comparison with synchronized Holter ECG recordings, sensitivity and positive predictive value of arrhythmia detection in comparison with Holter ECG and independent of it, and noise burden during the entire follow-up period.

RESULTS

The implantation was successful in all 152 patients. Two device-related serious adverse events (pocket infections) occurred by 3 months. The mean QRS amplitude of 0.3 ± 0.2 mV at implantation remained stable over 12 months. QRS sensing performance indicated little over- and undersensing in most patients. More than 80 % of the patients had more than 22 h of noise-free monitoring per day.

CONCLUSION

BioMonitor effectively detects patients with bradycardia, tachycardia, AF, or asystole. Active noise detection seems to reduce the transmission of meaningless data without diminishing the positive predictive value of the device.