The rear train was operating on "automatic" mode, which is routine during rush hour, and preliminary evidence shows that the driver may have employed the brakes, Hersman said.
To upload the data to a computer, a patient holds a small wand over his chest that picks up the data and transmits it through a modem to a Medtronic computer bank. (Future versions will be totally automatic and transmit wirelessly.) For now doctors mostly use the device to perform routine checkups remotely or to evaluate the device after it fires up.