br Remote technologies The platforms available for remote mo
Remote technologies The platforms available for remote monitoring of ICDs differ. Wand-based (“inductive”) systems require patient-driven downloads relayed via telephone connections to tracking facilities [4,5]. These are becoming obsolete. This is because they demand coordination with a device clinic on a calendar-based schedule, are cumbersome to use, challenge compliance and increase service burden without offering gain [6,7]. Important diagnostic data may be overwritten since device diagnostics have finite memory. Thus, when used to follow-up a pacemaker population, clinically actionable events took several months to be discovered, and only 66% of data were transmitted . These systems remain vulnerable to late detection of asymptomatic events, or of simply ones that the patient does not report but are potentially life-threatening (Fig. 1). In contrast, automatic (wireless or landline) transmission mechanisms are fully independent of patient and physician interaction (Fig. 2). (This makes them particularly suitable for children  and the elderly). Data may be reviewed securely via the Internet. This system was pioneered by Home Monitoring® (HM) (Biotronik, Berlin, Germany) with excellent reliability and early notification ability . 90% Of transmitted data were received within 5min with greater than 99% data fidelity. ICD generators were shown to self-declare problems promptly irrespective of interrogation schedules or associated symptoms [11,12]. System operation is not UM 171 costly . This technology has the ability to maintain surveillance and rapidly bring to attention significant data, enabling clinically appropriate intervention. These potentials have been tested prospectively in recent trials.
Clinical trials The first large remote monitoring trial was TRUST [11,14]. This randomized almost 1500 patients to remote management with HM or conventional face-to-face evaluations (Fig. 3, top left). HM promoted greater adherence to long-term follow-up without compromizing safety (this safety endpoint was endorsed in the ECOST trial during longer follow-up ). When inclusive of all patient encounters, (i.e. scheduled and unscheduled), health care utilization was reduced by ~50% (Fig. 3, top right). The second important result of TRUST was demonstration of early detection ability of clinical events during continuous remote monitoring. Despite extension of intervals between face-to-face encounters to yearly, event onset to physician evaluation of combined first AF, VT and VF events in HM was 1 day, dramatically less than in conventional care (>1 month) with frequent face to face encounters (Fig. 3, bottom left). Importantly, early detection was maintained for silent problems (Fig. 3, bottom right). (This ability was inconceivable even a few years previously with wanded remote systems when detection at 5.7 months was considered “early” ). Similar benefits were seen in pacemaker recipients in the COMPAS trial . Interestingly, the results suggested that remote monitoring could have an impact to decrease atrial arrhythmia and stroke related hospitalizations. The HomeGuide Registry confirmed that the high quality of remotely acquired data since the majority (>80%) of clinically meaningful events were remotely detected (sensitivity 84%; positive predictive value 97%) . The CONNECT trial followed up to TRUST with a similar study design but with a different wireless remote technology (Medtronic CareLink Network) in a separate ICD population . The results confirmed that remote interrogation effectively substituted for in-office visits and provided early detection capability. However, safety was not assessed. Furthermore, the susceptibility of this technology platform to transmission failure and the negative effects of multiple transmission attempts on battery longevity are significant drawbacks . When alert transmissions for some conditions were successful, manual reset was required to reactivate this notification ability, i.e. the ability for further notification in the interim was lost until an otherwise unnecessary in-person encounter could be arranged. This design, depending on patient interaction and single transmissions vulnerable to failure, limits its role as an early-warning mechanism.