A method and system of monitoring information received from a patient-worn medical device is disclosed. A medical device, such as a portable or implantable device, collects patient and operational information, which information is transmitted to central location, such as a doctor's office or device manufacturer's location. The data collected can be analyzed to monitor both the patient health parameters as well as the operation of the device. Trend analysis can be performed in order for a physician to diagnose the patient's health and a medical device technician can insure correct functioning of the device itself. Communication between the central location and the medical device is preferably done through a modem connection, and software and other updates can be automatically transmitted to the medical device during data download from the device to the central location. Physicians and technicians can access the central location from any home or office computer via the internet.