Arterial compliance

Soy isoflavones improve systemic arterial compliance but not plasma lipids in menopausal and perimenopausal women. Arterioscler Thromb Vase Biol. 17 (12) 3392-8. 

Nestel, P.J., Pomeroy, S., Kay, S., Komesaroff, P., Behrsing, J., Cameron, J.D. and West, L. (1999). Isoflavones from red clover improve systemic arterial compliance but not plasma lipids in menopausal women, J. Clin. Endocrinol. Metab., 84, 895-898. 

In a placebo-controlled, randomized, crossover study with 21 peri- and postmenopausal women treated for 5 weeks with a supplement delivering 80 mg total soy isoflavones/day, a significant improvement was reported in systemic arterial compliance, but had no etfect on flow-mediated vasodilation. This lack of an effect on flow-mediated vasodilation is in... 

Nestel, PJ, Yamashita T, Sasahara T, Pomeroy S, Dart A, Komesaroff P, Owen A, Abbey M. Soy isoflavones improve systemic arterial compliance but not plasma lipid in menopausal and perime-nopausal women. Arterioscler. Thromb. Vase. Biol. 17, 3392-3398, 1997. 

Teede HJ, Liang YL, Kotsopoulos D, Zoungas S, Craven R, McGrath BP. Placebo-controlled trial of transdermal estrogen therapy alone in postmenopausal women effects on arterial compliance and endothelial function. Climacteric 2002 5(2) 160-9. 

Brlnch, K., Moller, S., Bendtsen, F., Becker, U., Henriksen, J.H. Plasma volume expansion by albumin in cirrhosis. Relation to blood volume distribution, arterial compliance and severity of disease. X. Hepatol. 2003 39 24-31... 

Diseases of the heart and circulatory system, cardiovascular diseases, have long been the leading cause of mortality in Europe and North America, and total cholesterol and low-density lipoprotein (LDL) cholesterol are the two most important risk factors for coronary heart disease. Decreased arterial compliance of the arteries is thought to contribute to systolic hypertension and coronary artery insufficiency. A number of nutraceuticals have been used for long-term prevention or symptom reduction in cardiovascular diseases, notably soy products, tea flavonoids, octacosanol, n-3-polyunsaturated fatty acids (PUFAs), and, to a lesser extent, melatonin, Pycnogenol, resveratrol, coenzyme QIO, lycopene, and DHEA. 

There appears to be a strong link between arterial compliance or stiffness and atherosclerosis and systolic hypertension. In humans, supplementation with soy protein or isoflavones appears to improve com-pliance. In one placebo controlled, randomized, cross-over clinical trial on peri- and postmenopausal women, treatment with 80 mg/day purified soy isoflavones for 5 weeks resulted in improvement of ca. 26% in systemic arterial compliance, even though there was no reduction in blood lipids. Only one study demonstrated a significant decrease in blood pressure, reported in 51 non-hypertensive women after ingestion of 34 mg/day isoflavones,but other studies failed to show a significant effect. ... 

Nestel, P.J. T. Yamashita T. Sasahara S. Pomeroy A. Dart P. Komesaroff A. Owen M. Abbey. Soy isoflavones improve systemic arterial compliances but not plasma lipids in menopausal and peri-menopausal women. Arterioscler. Thromh. Vase. Biol. 1997,17, 3392-3398. 

Yamashita, T T. Sasahara S.E. Pomeroy G. Collier P.J. Nestel. Arterial compliance, blood pressure, plasma leptin, and plasma lipids in women are improved with weight reduction equally with a meat-based diet and a plant-based diet. Metabolism 1998, 47, 1308-1314. 

Kass DA, Shapiro EP, Kawaguchi M, et al. Improved arterial compliance by a novel advanced glycation end-product crosslink breaker. Circulation 2001 104 1464-1470. 

Zso=Systemic Characteristic Impedance CsA=Systemic Arterial Compliance Rsa=Systemic Peripheral Resistance Csv=Systemic Venous Compliance F 3v=Systemic Venous Resistance... 

Zpo= Pulmonic Characteristic Impedance CpA= Pulmonic Arterial Compliance RpA= Pulmonic Peripheral Resistance Cpv= Pulmonic Venous Compliance / pv= Pulmonic Venous Resistance... 

The physical relationships that govern the Windkessel model are now reviewed. Time dependency is provided by the blood volume storage property of arterial compliance, Cj. The time derivative of peripheral arterial pressure, Ps, is proportional to the difference in blood flow into and out of the compliance, according to,... 

The arterial compliance may be treated as a function of pressure also, accounting for large changes in blood pressure. The pressure dependence of compliance is then modeled by an exponential function [Liu... 

Quick, C.M., Berger, D.S., and Noordergraaf, A. 1998. Apparent arterial compliance. Am. J. Physiol. 274 H1393-H1403. 

Stergiopulos, N., Meister, J.-J., and Westerhof, N. 1995a. Evaluation of methods for estimation of total arterial compliance. Am. ]. Physiol. 268 H1540-H1548. 

Toorop, G.P., Westerhof, N., and Elzinga, G. 1987. Beat-to-beat estimation of peripheral resistance and arterial compliance during pressure transients. Am. J. Physiol. 252 H1275—H1283. 

Vascular compliance averages about 2 ml (mmHg-kg body weight). The majority is in the venules and veins. Arterial compliance is only about 0.05 ml/mmHg-kg. Skeletal muscle compliance is less than that of the body as a whole, whereas the vascular compliance of the liver is about 10 times that of other organs. The stressed volume is the product of compliance and mean filling pressure and so is about 15 ml/kg. By difference, the unstressed volume is about 60 ml/kg. 

Vitamin E inhibits the oxidation of low density lipoproteins (LDL), decreases monocyte adhesion to the endothelium, and cytotoxicity to endothelial cells it also inhibits platelet function, reduces the expression of cell adhesion molecules, improves arterial compliance, and inhibits vessel-wall thickening (9,10). 

Nestel, P, Shige, H., Pomeroy, S., Cehun, M., Abbey, M., and Raederstorff, D. (2002) The n-3 Fatty Acids Eicosapentaenoic Acid and Docosahexaenoic Acid Increase Systemic Arterial Compliance in Humans, Am. J. Clin. Nutr. 76,326-330. 

Another simple and usefiil expression is the arterial compliance per unit lengfli, C , that can be derived when the tube cross-sectional area A is related to the internal pressure A = A(P, z). For a thin-wall elastic tube (with internal radius Rq <1 wall thickness h), which is made of a hookean material (with Young modulus E), one can obtain the following useful relation. 

The role of ventricular resistance in the coupling of the ventricle to its arterial load was also investigated. For this purpose, a computer simulation study was performed where the LV was represented by the above model and the arterial load by a modified Windkessel (i.e., peripheral resistance, lumped arterial compliance and a characteristic impedance). It was observed that inclusion of a ventricular resistance slightly decreased mean arterial pressure (3 to 10%) and stroke volume (3 to 7%). In contrast, the pulsatile nature of the flow was markedly altered suggesting that ventricular resistance may play an important role in minimizing the external pulsatile power and in optimally coupling the ventricle to its arterial load (Shroff et ai, 1983a). 

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