Bifurcation in Blood Oscillatory Rhythms for Patients with Ischemic Stroke: A Small Scale Clinical Trial using Laser Doppler Flowmetry and Computational Modeling of Vasomotion

Abstract

We describe application of spectral analysis of laser Doppler flowmetry (LDF) signals to investigation of cerebrovascular haemodynamics in patients with post-acute ischemic stroke (AIS) and cerebrovascular insufficiency. LDF was performed from 3 to 7 days after the onset of AIS on forehead in the right and left supraorbital regions in patients. Analysis of LDF signals showed that perfusion in the microvasculature in AIS patients was lower than that in patients with cerebrovascular insufficiency. As a result of wavelet analysis of the LDF signals we obtained activation of the vasomotion in the frequency range of myogenic oscillation of 0.1 Hz and predominantly nutritive regime microcirculation after systemic thrombolytic therapy of the AIS patients. In case of significant stroke size, myogenic activity, and nutritive pattern microhaemodynamics were reduced, in some cases non-nutritive pattern and/or venular stasis was revealed. Wavelet analysis of the LDF signals also showed asymmetry in wavelet spectra of the LDF signals obtained in stroke-affected and unaffected hemispheres in the AIS patients. A mechanism underlying the observed asymmetry was analyzed by computational modeling of vasomotion developed in Arciero and Secomb (2012). We applied this model to describe relaxation oscillation of arteriole diameter which is forced by myogenic oscillation induced by synchronous calcium oscillation in vascular smooth muscle cells. Calculation showed that vasomotion frequency spectrum at the low-frequency range (0.01 Hz) is reciprocally modulated by myogenic oscillation (0.1 Hz) that correlates with experimental observation of inter-hemispheric variation in the LDF spectrum.

Nonlinear analysis of fluctuations of microcirculation parameters in symmetrical organs of humans by laser doppler flowmetry

“…Результаты исследования выявили специфичность регуляции колебательных процессов в микроциркуляторном русле, связанную с наличием функциональной асимметрии корреляционных взаимосвязей между различными показателями МЦР. Если корреляционные взаимосвязи между различными показателями МЦР одной стороны измерения могут быть объяснены в рамках существующих представлений и математических моделей регуляции микрокровотока [10,11], то относительно выявленного в настоящем исследовании феномена функциональной асимметрии корреляционных взаимосвязей между показателями МЦР противоположных сторон измерения этого сказать нельзя. Можно предположить, что одной из причин лево-правосторонней асимметрии показателей МЦР является исходная асимметрия морфологических характеристик сосудов симметричных органов [12], являющаяся проявлением одного из важных свойств морфофункциональной организации биологических систем -свойства хиральности.…”

Multimodal Optical Diagnostics of the Microhaemodynamics in Upper and Lower Limbs

“…The recent studies show that multiparametric approach in the form of joint measurements by various optical methods supplemented by functional tests can give complex information about the functional state of the microcirculation (Goltsov et al, 2017; Zherebtsov et al, 2017; Zherebtsova et al, 2017).…”

The march in place activity – a view from the local concentration of red blood cells (CRBC) in the human foot dorsum

“…Peripheral hemodynamics are not only influenced by the arteriolar branches embedded in the skeletal muscle, but also by the local endothelium controlling perfusion [8]. In cerebrovascular patients, an abnormal muscle activity and coordination are typically found, e.g., the early plantar flexor activity during stance or the early termination of tibialis anterior activity during swing [9]. The importance of these muscles to the normal peripheral perfusion might influence and even improve the overall function [10].…”

“…É importante considerar que a hemodinâmica periférica não é apenas influenciada pelos ramos arteriolares embutidos no músculo esquelético, mas também pelo endotélio local que controla o fluxo sanguíneo [8]. Nos pacientes cerebrovasculares, a atividade muscular e a coordenação de movimento encontra-se alterada, como é exemplo a diminuição da atividade dos flexores plantares durante a postura e movimento ou um término precoce da atividade tibial anterior durante o swing [9]. A importância do funcionamento dos músculos da perna pode determinar uma perfusão normal à periferia, e melhorar a função global do membro inferior [10].…”