External continuous loop recorders are attached to the patient by chest electrodes or a wristband. They continuously record the ECG but only save data if activated by the patient. The continuous looping memory feature allows the device to store a fixed length of pre-activation and post-event ECG data. Mobile cardiac telemetry systems provide up to 30 days of real-time continuous cardiac monitoring without the need for patient activation or data transmission. These devices are expensive, require electrodes and bulky recording devices, and produce a large amount of data, which requires sifting. Implantable loop recorders are surgically implanted subcutaneous devices that continuously record single-lead ECG signal through 2 electrodes. They are very expensive and necessitate an invasive surgical procedure. For patients admitted to hospital and who are placed on telemetry, there is also lack of consensus on the optimal duration of monitoring. Typically higher risk patients are monitored for 24 hours and discharged without a diagnosis if their ECG tracing has been uneventful during this time period.