Miniature microcontroller-based heart rate telemeter processes single precordial lead

A miniature single-channel heart rate monitoring device has been developed specifically for use in critical care situations, such as intensive care units. The externally-worn device is placed directly on the chest above the heart, allowing acquisition of the electrocardiogram without the use of leads. The 8-bit microcontroller-based transmitter digitizes the preconditioned ECG and identifies the signal in real-time using a robust QRS detection algorithm. Data is output from the microcontroller only when an abnormal heart rate or low battery voltage is detected. When it is necessary to output data from the device, the digital data is transmitted by frequency modulation to a nearby nurses´ station. At the monitoring station, the transmitted data is demodulated by the receiver and processed by another microcontroller which then activates the appropriate alarms