An electrocardiograph device and methods of navigating displays of such a device are disclosed. In one example, an electrocardiograph device includes a display, a plurality of electrocardiograph signal leads, and a programmable circuit. The programmable circuit is configured to receive electrical signals via the electrocardiograph signal leads representative of a heartbeat of a patient. The programmable circuit is configured to generate a user interface to be presented on the display, the user interface comprising a lead display including a screen layout including a plurality of waveform regions. The waveform regions display a waveform corresponding to an electrical signal from one of the leads over a time interval including at least one heartbeat period. Selection of a region causes display of an extended waveform region displaying a waveform over a second time interval that is longer than the first time interval, and which includes a plurality of heartbeat periods.