Po-03-052 failure of implantable cardiac monitor connectivity: lessons learned and implications for clinical care

Implantable cardiac monitors (ICMs) are capable of automatic daily data transmission. Multiple data transmission methods are available with recent emphasis on Bluetooth technology coupled with a smartphone-based app. However, the robustness of daily connectivity remains poorly understood. Evaluate ICM connectivity over a 90-day period and to determine if the data transmission method impacts connectivity. We enrolled all patients with an ICM (LINQII, Medtronic, Minneapolis) being followed in our practice as of September 1, 2022. All patients were prospectively followed for 90-days. Daily connectivity was determined based on an automated tool developed for our remote monitoring platform (91Life, New York) which retrieved the patient’s daily ECG, if available, from CareLink. We divided patients into 4 groups – always connected and maximal consecutive disconnected days of 1-3, 4-7, and >7 days. In addition, we compared the connectivity for the 3 types of transmitters: MyCareLink RelayTM bedside communicator; MyCareLink HeartTM mobile app on a patient owned phone; or MyCareLink HeartTM mobile app on a dedicated Medtronic provided phone. We followed 673 patients. The communication relay was the home communicator in 349 (52%), personal phone in 256 (38%), and Medtronic provided phone in 68 (10%) patients. There were isolated days with significant drop in connectivity (Figure, left, *) as well as one day where there was no patient connectivity (**). Overall, the average daily connectivity for the entire cohort was 89%; however, only 24% of patients achieved 100% continuous connectivity and 21% of patients were disconnected for >7 consecutive days (Table). This was significantly more likely when patients transmitted using a bedside communicator (Figure, right). (X2=52.7; df=2; p<0.00001) While overall daily connectivity of the LINQII ICM was 89%, uninterrupted connectivity was observed in only a quarter of patients over a 3-month observation period and approximately 20% were disconnected for more than a week at a time. There were days with unexplained large drops in connectivity. Finally, although there has been a major push to move to Bluetooth technology coupled with a smartphone for data transmission, we found this mode to be much less reliable than the traditional bedside communicator. These data have important implications for managing patients that need daily ECG monitoring to guide clinical decision making.Tabled 1Connectivity Patterns for Medtronic LINQll Implantable Cardiac Monitors100% Connected (n,%)1-3 Days Disconnected (n,%)4-7 Days Disconnected (n/%)>7 Days Disconnected (n,%)161, 24%277,41%94, 14%141, 21% Open table in a new tab