An ECG monitoring system for ambulatory patients includes a small multi-electrode patch that adhesively attaches to the chest of a patient. A reusable battery-powered ECG monitor clips onto the patch and receives patient electrical signals from the electrodes of the patch. A processor continuously processes received ECG signals and analyzes the received ECG signals for pre-defined arrhythmia. If an arrhythmia is detected, a wireless transceiver in the ECG monitor transmits the event information and an ECG strip to a monitoring center. At the commencement of a monitoring procedure a message is sent to the monitoring center and configuration information for arrhythmia detection is down-loaded and installed in the monitor. The configuration file is determined by a screen of selectable standard and custom arrhythmias and alarm limits at the monitoring center.
