"Home monitoring" for early detection of implantable cardioverter-defibrillator failure

Telemedical ICD monitoring has the potential to enhance patient safety. The "home-monitoring" (HM) feature transmits selected device-related data to a service-center via mobile phone network. In case of a potential emergency situation, event reports are generated automatically. This prospective observational study was designed to test whether HM is effective and reliable in early detection of device failure. Consecutive patients receiving ICD, CRT-D or CRT pacemaker systems with HM feature were included. Regular follow-up visits were performed 1, 3, 6, 9 and 12 months after implantation in the first year, and every 6 months thereafter. All event reports transmitted by HM were analyzed and severe device-related events (serious lead or device dysfunction, hospitalization, death) were documented including timing, type and mode of detection. Sixty-nine patients were included and followed for 18 +/- A 9 months. A total of 206 event reports were transmitted, prompted by VF/VT-episodes (n = 193), ineffective ICD shocks (n = 7), abnormal pacing impedance (n = 4) or battery depletion (n = 2). 8 SAEs were observed (RV lead fracture; n = 5, connector defect; n = 1, sensing defect, n = 1, RV lead dislodgement, n = 1). There was no device-related death. 6 out of 8 SAEs were discovered by HM (sensitivity, 75%). Without HM, these events would have been detected with a theoretical delay of 1.9 +/- A 0.5 months in the first year (3 monthly FU) and 4.9 +/- A 0.5 months in the following years (6 monthly FU). This pilot study demonstrates that HM enables early detection of ICD failure and appears to enhance patient safety.