title: Spectral analysis of laser Doppler skin blood flow oscillations in human essential arterial hypertension.
abstract: The aim of this study was to investigate whether human essential arterial hypertension (EHT) is associated with modification of the skin blood flowmotion (SBF), which could be a sign of skin microcirculatory impairment. Forearm skin perfusion was measured by laser Doppler flowmetry (LDF) in conventional perfusion units (PU) before and after ischemia in 20 middle-age newly diagnosed EHT untreated patients, in 20 middle-age long standing EHT treated patients and in 30 age and sex matched healthy normotensive subjects (NS). Power spectral density (PSD) of SBF total spectrum (0.009-1.6 Hz), as well of five different frequency intervals (FI), each of them related to endothelial (0.009-0.02 Hz), sympathetic (0.02-0.06 Hz), myogenic (0.06-0.2 Hz), respiratory (0.2-0.6) or cardiac (0.6-1.6) activity, was also measured in PU(2)/Hz before and after ishemia, using Fourier analysis of LDF signal. The three studied groups did not differ in basal and post-ischemic skin perfusion or in basal SBF parameters considered. However, while a significant post-ischemic increase in PSD of total spectrum SBF (P < 0.001) and of its different FI, with the only exception of respiratory FI, was observed in NS, a significsnt post-ischemic increase in PSD was observed only for total spectrum (P < 0.01) and for endothelial FI (P < 0.001) in newly diagnosed EHT patients and only for myogenic FI (P < 0.05) in long standing EHT patients. These findings suggest that the mechanisms which mediate the post-ischemic increment of SBF are perturbed earlier in human EHT than the mechanisms which mediate the skin post-ischemic hyperaemia. The same findings also suggest that the impairment of the endothelial mechanism involved in SBF control occurs by the time in the course of EHT.
authors.affiliation: University of Pisa, mrossi@int.med.unipi.it
authors.forename: Marco
authors.initials: M
authors.lastname: Rossi
authors.forename: Angelo
authors.initials: A
authors.lastname: Carpi
authors.forename: Cinzia
authors.initials: C
authors.lastname: Di Maria
authors.forename: Fabio
authors.initials: F
authors.lastname: Galetta
authors.forename: Gino
authors.initials: G
authors.lastname: Santoro
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity; D016022:Case-Control Studies; D003935:Diagnostic Techniques, Cardiovascular; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000175:diagnosis*; D017078:Laser-Doppler Flowmetry / Q000379:methods*; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D009991:Oscillometry; D012039:Regional Blood Flow; D012867:Skin / Q000098:blood supply* / Q000473:pathology