Role of arterial design on pulse wave reflection in a fractal pulmonary network

被引:25
作者
Bennett, SH
Goetzman, BW
Milstein, JM
Pannu, JS
机构
[1] Division of Neonatology, Department of Pediatrics, University of California, Davis
关键词
hemodynamics; input impedance; network connectivity;
D O I
10.1152/jappl.1996.80.3.1033
中图分类号
Q4 [生理学];
学科分类号
071003 ;
摘要
A novel interpretation of pulmonary arterial input impedance was evaluated for the lung as a fractal vascular network. We hypothesized that local sources of reflection introduce trends of global reflection into the input impedance spectra. These trends are related to the network topology, geometry, and design according to R(b) = R(d)(x), where R(b) is the branching ratio, R(d) is the diameter ratio, and x is the fractal dimension quantifying design. Simulations using values of R(d) and x, which were derived morphometrically, confirmed two patterns of global reflection: a continuous trend attributed to a single effective site of reflection caused by frequency-dependent sources of impedance contrast and a discrete trend arising from a longitudinal distribution of frequency-independent sources of reflection. The continuous trend depended only on the network parameter R(d), whereas the discrete trend depended on R(d) and x. Our results indicate that the impedance-matching properties of a deterministic pulmonary fractal network encode arterial geometry and topology via function and that typical values of R(d) and x for the pulmonary circulation facilitate shear stress amplification in its peripheral vessels. Thus, inasmuch as shear forces may be involved in the endothelial mechanisms for pathological, or physiological, vascular remodeling, broadband input impedance analysis may reveal interactions between network organization and vascular function.
引用
收藏
页码:1033 / 1056
页数:24
相关论文
共 76 条
[1]  
[Anonymous], 1952, B MATH BIOPHYS, DOI [DOI 10.1007/BF02477850, 10.1007/bf02477850]
[2]  
[Anonymous], FRACTALS CHAOS POWER
[3]  
BELIK J, 1994, AM J PHYSIOL, V266, pH2303, DOI 10.1152/ajpheart.1994.266.6.H2303
[4]  
BENNETT S, 1994, J APPL PHYSIOL, V75, P455
[5]   PULMONARY VASCULAR IMPEDANCE IN DOG [J].
BERGEL, DH ;
MILNOR, WR .
CIRCULATION RESEARCH, 1965, 16 (05) :401-&
[6]   REPEATED REFLECTION OF WAVES IN THE SYSTEMIC ARTERIAL SYSTEM [J].
BERGER, DS ;
LI, JKJ ;
LASKEY, WK ;
NOORDERGRAAF, A .
AMERICAN JOURNAL OF PHYSIOLOGY, 1993, 264 (01) :H269-H281
[7]  
BOURBIE T, 1982, THESIS EFFECTS ATTEN
[8]   EFFECT OF NITROPRUSSIDE ON WAVE REFLECTIONS IN PATIENTS WITH HEART-FAILURE [J].
BRIN, KP ;
YIN, FCP .
ANNALS OF BIOMEDICAL ENGINEERING, 1984, 12 (02) :135-150
[9]   LIMITS ON THE CONTINUOUS DISTRIBUTION OF PULMONARY VASCULAR-RESISTANCE VERSUS COMPLIANCE FROM OUTFLOW OCCLUSION [J].
BRONIKOWSKI, TA ;
DAWSON, CA ;
LINEHAN, JH .
MICROVASCULAR RESEARCH, 1985, 30 (03) :306-313
[10]   IMPEDANCE MATCHING AT ARTERIAL BIFURCATIONS [J].
BROWN, N .
JOURNAL OF BIOMECHANICS, 1993, 26 (01) :59-67