Non-linear dynamic processes and their correlation with indicators of microcirculation in patients with obliterating atherosclerosis of the lower extremities arteries according to laser doppler flowmetry

Objective: To study features of nonlinear dynamic and oscillatory processes in the skin microcirculatory flow in patients with obliterating atherosclerosis in lower extremities arteries (OALEA).

Material and methods. 56 male patients with obliterating atherosclerosis in the arteries of lower extremities and 15 practically healthy individuals were taken into the study. Microcirculation in the skin on feet with the assessment of nonlinear dynamic processes and spectral wavelet analysis of blood fl ow fl uctuations was studied by laser Doppler flowmetry, device “LACK-M” (firm Lazma, Russia). Normalized amplitude parameters of blood flow fluctuations in frequency ranges of hemocirculation tonus-forming factors were analyzed: endothelial, neurogenic, myogenic. Myogenic microvascular tone and capillary blood flow indices were calculated. To study nonlinear dynamic processes, the following parameters were assessed: fractal dimension, entropy and phase portrait analysis.

Results. Spastic-atonic microcirculation disorders were revealed in patients with OALEA. They were characterized with metarteriole constriction and with restriction of capillary blood flow, with an increased myogenic tone and dilated arterioles. Statistically significant shifts in parameters of nonlinear dynamics in this case- in particular, decrease in entropy (–10.6 %) and in dimensions of phase portrait (–9.3%) under energy deficit in oscillatory microcirculation processes (–20.8 %) – can be interpreted as a decrease in complexity of laser Doppler flowmetric signal and better ordering in regulatory mechanisms of the peripheral blood flow.

Conclusion. In patients with obliterating atherosclerosis in the arteries of lower extremities, the obtained results indicate significant functional microcirculation disorders of the spastic-atonic nature leading to the restriction of nutritive blood flow and accompanied by the lack of energy in oscillatory processes. These results have also shown the decrease in the system chaos severity which indicates limitation of connections of microcirculation control factors, simplification of the mechanisms of functioning of the microvascular bed and, as a consequence, decrease in the compensatory adaptive potential.

1. Sudakov K.V. Functional systems. – Moscow: RAMS, 2011: 319 p. [In Russ.].

2. Halepo O.V., Molotkov O.V., Zinchuk V.V., Kozlov V.I., Duvanskiy V.A. Microcirculation and endothelial function: theoretical foundations, principles of diagnosis of disorders, signifi cance for clinical practice: scientifi c and methodological manual: Publisher: Duet-Print LLC printing house. Smolensk, 2015; 111p. [In Russ.].

3. Duvanskiy V.A., Azizov G.A. Features of regional microcirculation in patients with chronic venous insufficiency stage C6. Laser medicine. 2011; 15(1): 12–15. [In Russ.].

4. Bezruchko B.P., Koronovskij A.A., Trubeckov D.I., Hramov A.E. A way to the synergetics: An insight in 10 lectures.Moscow: Lenand, 2015: 304. [In Russ.].

5. Krupatkin A.I., Sidorov V.V. Functional diagnostics of microcirculatory-tissue systems: Fluctuations, information, nonlinearity. Guide for Physicians. Moscow: Librokom, 2013: 496. [In Russ.].

6. Carr R.T., Lacoin М. Nonlinear dynamics of microvascular blood fl ow. Ann Biomed Eng. 2000; 28 (6): 641–652. DOI:10.1114/1.1306346

7. Kozlov V.I., Azizov G.A., Gurova O.A., Litvin F.B. Laser Doppler flowmetry in assessing the state and disorders in blood microcirculation. Moscow: RUDN, 2012. 31 p. [In Russ.].

8. Krupatkin A.I., Sidorov V.V., Kucherik A.O., Troitsky D.P. Modern possibilities to analyze the behavior of microhemocirculation as a nonlinear dynamic system. Regionarnoye krovoobraschenie i microtzirculiatzia. 2010; 9(1): 61–67. [In Russ.].

9. Tankanag A.V., Tikhonova I.V., Chemeris N.K. Nonlinear analysis of changing in dynamics of cutaneous blood flow during the aging process in human. Vestnik novikh meditzinskih technologiy. 2006; 13(3): 96–98. [In Russ.].

10. Pincus S.M., Goldberger A.L. Physiological time-series analysis: what does regularity quantify? Am J Physiol. 1994; 266(4Pt2): H1643–56. DOI:10.1152/ajpheart.1994.266.4.H1643

11. Skinner J.E., Pratt C.M., Vybiral T. A reduction in the correlation dimension of heartbeat intervals precedes imminent ventricular fibrillation in human subjects. Am Heart J. 1993; 125(3): 731-43. DOI:10.1016/0002-8703(93)90165-6