Personal computer-based analysis of heart rate fluctuations in human subjects (ECG)

A personal-computer-based system for quantitation of spontaneous and provoked heart rate fluctuations in a clinical setting is described. The system was developed for screening and subsequent follow-up of neurological patients with autonomic-nervous-system lesions. The testing battery includes the Valsalva maneuver, a deep breathing test, a sustained handgrip test, face immersion, an orthostatic test and spectral analysis of heart rate variability in the supine and standing positions. The results of these tests performed on a group of 79 healthy volunteers of both sexes, aged 21 to 60 years, demonstrate the dependence of cardiovascular reactivity on age and its independence of sex.