A Microcomputer-Based Heart-Rate Variability Monitor

A cost-effective method of on-line measurement of beat-to-beat heart-rate variability is presented. Based on a commercial microcomputer, the data is formatted as a histogram covering up to 500 past events in the form of a moving time window. Analysis of the QRS peak detector used in the instrumentation shows the conditions necessary for 1 ms resolution. The system permits the on-line calculation of statistical parameters, which are presented when a hard copy of the histogram is requested.