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3. System Description
The ACT Continuous ECG Monitor and Arrhythmia Detector is
designed for self-testing by patients at home and for analysis by
trained technicians at a remote Monitoring Center.
The sensor is used for the acquisition and transmission of the ECG
signal. The sensor is equipped with three (ACT I) or four (ACT III)
electrodes on a harness and works in conjunction with a cell phone
monitor.
The sensor houses a 3.6V AA lithium-thionyl chloride battery, an ECG
channel circuit, an impedance measurement circuit, a pacemaker
detection circuit, a flash buffer memory, a Bluetooth transceiver and a
buzzer. The ECG signals are received, filtered and amplified in the
input circuit, stored in the flash memory buffer and transmitted via
Bluetooth to a cell phone monitor. The cell phone monitor runs a
proprietary application that is configured to process and transmit the
ECG recordings via a cellular network while storing them and the
detected physiological events on a micro-SD memory card. When a
physiological event is detected, the cell phone monitor transmits the
recorded ECG automatically via cellular link, to a Monitoring Center
for professional analysis. If the patient is out of the cellular network
coverage area, the cell phone monitor will send all events that were
stored when the cellular link is re-established. The cell phone monitor
can also transmit ECG alarms via landline telephone with an
additional POTS Bluetooth modem.
The sensor loops up to 2 hours (ACT I) or 6 hours (ACT III) cyclic
buffer of ECG data in the internal flash memory in order to preserve
the ECG in cases when the Bluetooth connection to the cell phone
monitor is down.
Note
The cell phone monitor automatically transmits the
detected ECG events to the monitoring center and the
user has the ability to send manually recorded events.
The data is saved on the storage card and the event
data is deleted after a successful transmission to the
monitoring center.
