Mudraya I.S.,Federal Agency for Health Care and Social Development |
Nesterov A.V.,BIOLA Scientific and Production Company |
Gavrilov I.Yu.,BIOLA Scientific and Production Company |
Selector L.Ya.,BIOLA Scientific and Production Company |
Revenko S.V.,BIOLA Scientific and Production Company
Bulletin of Experimental Biology and Medicine | Year: 2010
Fourier analysis was employed to determine the amplitudes of spectrum components of small variations of electrical resistance (bioimpedance) in human fi nger recorded using an original hardware-software complex. It revealed periodic bioimpedance oscillations at the frequencies of heartbeats, respiration, and Mayer wave (0.1 Hz). These periodic variations were observed under normal conditions and during circulation arrest in the arm. It is concluded that the spectrum peaks of bioimpedance variations in the phalanx of human fi nger refl ect periodic blood pressure changes in the major vessels and rhythmic neural control of the regional vascular tone. During normal blood fl ow, the greatest amplitude of rhythmic changes in bioimpedance was observed at the heart rate; it surpassed by an order of magnitude the amplitudes of respiratory oscillations and Mayer wave. In contrast, the largest amplitude of rhythmical changes of the impedance during circulation arrest corresponded to the oscillations at respiration rate, while the amplitude of variations at the heart rate was the smallest. Under circulation arrest, the maximum frequency of bioimpedance variations was approximately 1.4 Hz (the third respiratory harmonic), which indicates the upper limit of frequency range of neural modulation of vascular tone in human fi nger. During normal respiration and circulation, two side cardiac peaks were revealed in bioimpedance amplitude spectrum, whose amplitude refl ected the depth of the respiratory amplitude modulation of pumping action of the heart. During normal breathing, the second and the third harmonics of the cardiac bioimpedance variations were split refl ecting respiratory frequency modulation of the heart rate. © 2010 Springer Science+Business Media, Inc.
Markosyan T.G.,Moscow State University |
Alyaev Y.G.,Moscow State University |
Glybochko P.V.,Moscow State University |
Kirpatovsky V.I.,Research Institute of Urology |
And 4 more authors.
Bulletin of Experimental Biology and Medicine | Year: 2011
Small variations of electric impedance (bioimpedance) of human penis were examined in healthy volunteers and in patients with vascular erectile dysfunction (ED). The harmonic analysis revealed rhythmic oscillations of penile bioimpedance at frequencies corresponding to the heart and respiration rates and Mayer wave (0.1 Hz) and to multiple frequencies (harmonics) of the respiratory and cardiac oscillations. In normal penile bioimpedance spectrum, the Mayer and respiratory peaks were several times higher than the fi rst cardiac (pulsatile) harmonic indicating neurogenic origin of rhythmic bioimpedance variations in the whole penis. The most of healthy individuals (78%) demonstrated the cardiac harmonics at the frequency range of 4-7 Hz that violated the monotone decrement of the pulsatile harmonic series suggesting the resonant character of oscillations of the penile arteries at this "near" frequency range. In contrast to stable 1-4 cardiac harmonics, the amplitudes of the near-range resonant harmonics could vary during few minutes suggesting a causal relation of the corresponding bioimpedance oscillations with the varying vascular tone in penile arteries. The most patients (89%) with vascular ED demonstrated not only the fi rst 1-4 monotonically decrementing harmonics and the near-resonant ones, but also the stable cardiac harmonics at the "far" frequency range of 8-14 Hz that also disturbed the monotonic character of the cardiac harmonic series indicating the sclerotic alterations in regional arteries. In ED patients, insignifi cant decrease of the initial cardiac harmonics C1-C3 in comparison with the norm was accompanied by pronounced and signifi cant decrease of the respiratory R1 and Mayer M1 peaks. The study showed that the far-frequency bioimpedance resonances at the range of 8-14 Hz and dramatic drop of Mayer and respiratory peaks are the diagnostic signs of vascular ED independent on the accompanying hormonal or neurogenic disorders. © 2011 Springer Science+Business Media, Inc.