We present a mathematical model of forearm haemodynamics for assessing short term autonomic regulation of peripheral circulation. Non-invasive, continuous time measurements of omeral blood flow, ...viewed as the input to the model, and finger blood pressure, viewed as the output, are analyzed. The model has been used for beat-to-beat analysis of the dynamic blood flow/pressure relationship and has proven robust with respect to the large time-course changes in measured variables induced by the Valsalva manoeuvre. Our results showed a marked modulation of peripheral vasoconstriction in healthy subjects, which was less pronounced or even absent in patients with autonomic dysfunction. Our approach may thus become useful for assessing in clinical routine short term regulation of peripheral circulation in cardiovascular neuropathies.
The authors present a computerized system that has been developed for the automated analysis of cardiovascular reflex tests and for spectral analysis of R-R interval variations. Results from a study ...on diabetic autonomic neuropathy are presented, with particular reference to the relationship existing between cardiovascular reflex tests and spectral analysis. The standardized battery of cardiovascular reflex tests are described and compared to the spectral analysis approach on the basis of results obtained in 20 normal subjects and 53 diabetics presenting different degrees of autonomic involvement.< >
A non-invasive versatile system was used to measure baroreflex sensitivity and autonomic sympathetic activity during the standardized Valsalva maneuver. This method, in spite of its simplicity, ...allowed calculation of some indexes to measure the extent of baroreflex function and cardiovascular sympathetic modulation during phase 2 and phase 4 of this maneuver. The authors describe the technical tool for diagnosis of barosystem impairment and autonomic dysfunctions in clinical practice.< >
