[Correlations of heart rate and arterial pressure in the orthoclinostatic test. Study of 3500 subjects].

The study deals with the data resulting from the analysis of 3497 passive orthoclinostatic tests performed in the neurological Clinic of Pisa during the last 10 years. Blood pressure and heart rate values both in supine and upright positions have been analyzed, particularly focusing the orthostatic hypotension, which were 184 over 3497 tests. The results show that in young subjects only hypersympatheticotonic hypotension are present, due to a dysfunction of the regulating hypothalamic centres, while at more advanced age there is a prevalence of orthostatic hypotension with low differential values of heart rate. Differential values of heart rate as a function of age have been the calculated.