Timely transmission of alert events and prompt management of ventricular arrhythmias using app-based remote monitoring in a patient with a cardiac implantable electronic device

Figures

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  Figure 1. Alert event transmitted via the mobile app. A representative case of a patient with CRT-D showing an alert for shock therapy after VT refractory to multiple ATP attempts, transmitted via the mobile app. VT occurred at 11:30 AM, and shock therapy was delivered 1 minute later. The transmission occurred at 11:35 AM, with a delay of only 4 minutes from therapy delivery. Although the patient was away from home at the time of VT onset, the event was successfully transmitted via the smartphone-based mobile app. ATP = antitachycardia pacing; CRT-D = cardiac resynchronization therapy with defibrillator; HF = heart failure; iATP = intrinsic antitachycardia pacing; VF = ventricular fibrillation; VT = ventricular tachycardia.

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  Figure 2. Alert event transmitted via the home communicator monitoring system. The same patient as shown in Figure 1 previously used a home communicator system before switching to the mobile app. An alert event for VT successfully treated with ATP occurred at 1:24 PM; however, transmission was delayed until 3:48 PM, resulting in a time lag of more than 2 hours. Abbreviations as in Figure 1.

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  Figure 3. Comparison of transmission times between the app-based and home communicator systems. 25 and 14 alert events were recorded with the app-based system and home communicator system, respectively. Detailed events were 8 weekly ATP delivered alerts, 6 shock therapy alerts, 5 AF daily burden alerts, 2 daily VT/VF episodes ≥3 alerts, 2 total VP <90% alerts, 1 episode of OptiVol 2.0 (Medtronic, Minneapolis, MN) fluid settings ≥120 alert, and 1 episode of pacing lead impedance out-of-range alert. In contrast, all events were atrial fibrillation daily burden alerts except for 1 event of weekly ATP delivered alerts in the home communicator system. Because all episodes were derived from a single patient, the comparison was descriptive. The Fisher exact test was used as an exploratory analysis, and no adjustment for within-patient clustering was performed in the rate comparison. Permission to use the mobile app and home communicator images was obtained from Medtronic Japan. AF = atrial fibrillation; AT = atrial tachycardia; LV = left ventricular; VP = ventricular pacing; other abbreviations as in Figure 1.