Clinical Hemorheology and Microcirculation - Volume 35, issue 1-2

Authors: Késmárky, Gábor | Fehér, Gergely | Koltai, Katalin | Horváth, Beáta | Tóth, Kálmán

Article Type: Research Article

Abstract: Background: In atherosclerotic diseases vascular reserve is impaired and pressure gradient is decreased, therefore the reduced blood fluidity can lead to tissue ischemia more rapidly. In previous investigations we demonstrated the deterioration of plasma and whole blood viscosities in patients with acute ischemic coronary syndromes, chronic coronary artery disease, and percutaneous transluminal coronary angioplasty. Methods: Hemorheological variables (plasma and whole blood viscosities, hematocrit, red blood cell aggregation), hemostaseological parameters (plasma fibrinogen and von Willebrand factor (vWf)), and platelet aggregation were detected in more recent studies in cardio- and cerebrovascular diseases, and diabetes mellitus. Common risk factors (lipid profile, smoking, glucose …level, previous diseases) and medication were also recorded. Results: High portion of vascular patients were demonstrated to have poor ex vivo platelet inhibition. Effective antiplatelet treatment detected by aggregometry was related to lower plasma fibrinogen concentration and red blood cell aggregation and was also associated with less recurrent vascular events during the follow-up (p<0.001). Beside the impaired hemorheological characteristics, the diabetic patients showed elevated vWf activity, which turned to correlate with hemoglobin A1c concentration (p<0.01) rather than the fasting glucose. Summary: Our studies indicate the active role and interaction of hemorheological and hemostaseological factors in atherosclerotic heart diseases. Show more

Keywords: Viscosity, hemostasis, ischemic heart disease

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 67-73, 2006

Authors: Pongrácz, Endre | Andrikovics, Hajnalka | Csornai, Márta | Bernát, Iván S. | Nagy, Zoltán

Article Type: Research Article

Abstract: The concentration of plasma fibrinogen (FIB) is an important factor in the coagulation cascade and also in the determination of blood and plasma viscosity depending on both genetic and acquired factors. The -455G/A polymorphism of the β-FIB gene is connected to the plasma concentration of FIB but the effect of Leiden mutation on hemorheological parameters is unclear. The two genetic polymorphisms were studied by polymerase chain reaction in healthy subjects and ischemic stroke cohort and the effects on the concentration of plasma FIB, whole blood and plasma viscosity of patients as well. A total of 278 ischemic stroke patients and …173 control subjects were enrolled. Marcro-rheological parameters as plasma FIB concentration, whole blood viscosity (90 sec−1 shear rate) and plasma viscosity have been measured also in the subgroup of young (age<50 years) and in a subgroup of non-smoker patients. Results: No significant difference was found in the prevalency of H1/H2 genotype between controls and cases in pooled stroke group OR 0.95 (95% CI: 0.47–1.27), however H2/H2 genotype frequency was increased in young subgroup of patients (OR: 1.66 95% CI: 0.52–5.25). Plasma FIB concentration was increased both in the total cohort (p<0.05) and in the non-smoker subgroup (p<0.03) of patients carried H2/H2 as compared to H1/H1 genotype and the prevalence was increased in the group of patients having plasma FIB concentration >4 g/l (p<0.05). The whole blood viscosity was elevated in the H2/H2 group as compared to the group carrying wild type (p<0.03). A tendency of increased plasma viscosity in the group of patients with H2/H2 genotype as compared to wild type was found (p=0.07). Leiden mutation prevalence showed an increased risk OR: 1.67 (95% CI: 0.75–3.70) in the young patients group as compared to controls. In patients who have had the highest plasma viscosity, higher frequency of Leiden mutation was detected as compared to wild type, in total group (p=0.01), in young patients (p=0.03) and in subgroup of non-smoker patients (p=0.05). Conclusions: Our findings support the notion that the homozigous variant of β-FIB gene can raise both plasma FIB concentration and whole blood viscosity. Leiden mutation connected to the elevation of plasma viscosity could demonstrate a new pathway of increased thrombophylic potential in ischemic stroke patients. Show more

Keywords: Ischemic stroke, genetic polymorphisms, -445 β-fibrinogen, Leiden mutation, blood viscosity, plasma viscosity, hemorheology

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 75-82, 2006

Authors: Kovács, Ágnes | Szikszai, Zita | Várady, Éva | Imre, Sándor

Article Type: Research Article

Abstract: The aim of this study was to assess social and health status of residents older than 90 years in an East-Hungarian city. The investigation involved 70 subjects, measuring routine laboratory parameters and plasma viscosity. Mean cholesterol, erythrocyte sedimentation rate (ESR), collagen cross links and plasma viscosity values exceeded the reference range, but mean red blood cell count, hematocrit and hemoglobin were below it. Plasma viscosity was found pathologically elevated in 51% of cases. We compared these results with an earlier laboratory screening test performed on the same population with the age range of 60 to 90 years. In this cohort …the mean fibrinogen concentration, ESR, HDL-cholesterol and collagen cross links values were higher, but mean cholesterol, triglyceride, total protein, hemoglobin and hematocrit values were lower than the reference range. Show more

Keywords: Oldest-old, laboratory parameters, plasma viscosity, aging

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 83-88, 2006

Authors: Feher, Gergely | Koltai, Katalin | Kesmarky, Gabor | Szapary, Laszlo | Juricskay, Istvan | Toth, Kalman

Article Type: Research Article

Abstract: Background: There is increasing evidence that impaired hemorheological parameters are associated with increased risk of cardio- and cerebrovascular events. The aim of our present study was to examine the relationship of these parameters to the advancing age. Methods: The data of 6236 cardio- and cerebrovascular patients (3774 males, mean age 59.8±13.2 years and 2462 females, mean age 60.9±12.8 years) were included into this analysis. Males and females were divided into three groups, A < 45 years of age (young), B 45–65 years (middle-aged), C > 65 years (old). To exclude the effect of risk profile, previous diseases and medication, 623 …patients (397 males, mean age 60.2±12.7 yrs and 226 females, mean age 60.5±12.4 yrs) were selected from the examined group with matching parameters. Blood was collected after an overnight fasting. Hematocrit, fibrinogen, red blood cell aggregation, plasma and whole blood viscosity were determined. Results: All the measured parameters correlated significantly with advancing age in the whole population (p<0.01), however the values of the correlation coefficients were very low. On the other hand, examining the different age-groups we found that these parameters did not consequently correlate with age, in fact hematocrit, red blood cell aggregation and whole blood viscosity values were negatively correlated with age in old males (p<0.05). In the selected population these parameters did not correlate with advancing age. Conclusions: In the whole population the correlation of hemorheological parameters and advancing age may be just of statistical, but not clinical significance because of the high number of subjects. In the selected population these parameters did not correlate with advancing age. Our results suggest that these parameters are mostly independent of aging, increased values are not associated with older age but the more frequently occurring diseases. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 89-98, 2006

Authors: Bogar, L. | Juricskay, I. | Kesmarky, G. | Feher, G. | Kenyeres, P. | Toth, K.

Article Type: Research Article

Abstract: Plasma fibrinogen concentration, plasma and whole blood viscosity (WBV) are independent risk factors of coronary artery disease (CAD). Fibrinogen seems to be a relatively stronger risk factor for women than for men, but men are more endangered by higher hematocrit (Hct) and WBV than women are. We have previously reported that a theoretically optimal Hct value can be determined using Hct/WBV ratio in healthy subjects, hyperlipidemic and Raynaud's disease patients. Our aim was to examine whether Hct/WBV ratio is differently correlated with Hct in men and women with proven CAD. In a retrospective study we analysed the hemorheological data of …162 CAD outpatients (107 men and 55 women). Coronary angiography, echocardiography and impedance cardiography were performed. Hemorheological parameters (Hct, fibrinogen level, plasma viscosity, WBV), blood picture, serum lipid concentrations were determined and Hct/WBV ratio was calculated. Mean ages of male and female patients were similar (54.9 and 55.4 years, respectively), but men had significantly higher coronary angiography score than women. Mean left ventricular ejection fraction, stroke volume index and cardiac index showed no significant differences in men and women. Similarly, lipid concentrations, fibrinogen levels and plasma viscosities demonstrated no statistical differences. However, Hct, WBV and Hct/WBV ratios were significantly higher in male than in female patients (p<0.00001; p<0.00001 and p<0.005, respectively). The most striking gender difference was found in the correlation between Hct/WBV ratio and cardiac index. Men older than 56 years showed negative, women positive correlation (r=−0.485, p=0.01; r=0.468, p=0.006, respectively). This study demonstrates that Hct/WBV ratio as a rheological oxygen carrying capacity parameter is positively correlated with the cardiac index as it can be expected. However, the correlation is negative in elder men indicating an unhealthy relation between hemodynamic and hemorheologic parameters. Show more

Keywords: Coronary angiography, cardiac index, hemodynamics, hematocrit, blood viscosity, hemorheology

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 99-103, 2006

Authors: Matschke, K. | Tugtekin, S.M. | Knaut, M. | Mrowietz, C. | Park, J.-W. | Jung, F.

Article Type: Research Article

Abstract: Background: Experimental data have shown the potential risk of cellular damage of the myocardium during extra corporeal circulation (ECC). The influence of ECC on myocardial oxygen tension however remained unclear. Therefore, the influence of ECC on the oxygen tension in a beating heart was investigated. Methods: In a pig animal model flexible pO2 microcatheters were positioned in the midmyocardium of the left ventricle and the skeletal muscle and tissue oxygen tension during ECC were monitored and compared with data of a control group without ECC. Results: ECC and unload of the heart caused a significantly higher increase of myocardial …pO2 than in a non-ECC control group. Conclusion: Our findings show the beneficial effect of ECC on myocardial pO2 . This may support the use of ECC in coronary artery bypass grafting because the potential myocardial injury due to ECC is not related to myocardial ischemia. On the contrary, myocardial pO2 was even increased during extracorporeal circulation in this study. Show more

Keywords: Extra corporeal circulation, microcirculation, myocardium, left ventrical, tissue oxygen tension

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 105-111, 2006

Authors: Aloulou, Ikram | Varlet-Marie, Emmanuelle | Mercier, Jacques | Brun, Jean-Frédéric

Article Type: Research Article

Abstract: The metabolic syndrome which is at high risk for diabetes and atherothrombosis is associated with hemorheologic abnormalities. Initially, insulin resistance was considered as the core of the syndrome. However, it becomes clear that the syndrome is a cluster in which the combined effects of obesity, insulin resistance, and hyperinsulinemia can be inconstantly associated, contributing to a various extent to a global impairment of blood rheology. We previously reported in 157 nondiabetic subjects that both obesity and insulin resistance increase red cell rigidity (Dintenfass's Tk) and plasma viscosity (ηp ), and that whole blood viscosity at high shear rate (ηb …1000 s−1 ) reflects rather obesity than insulin resistance. In this study we aimed at defining the specific hemorheologic profile of insulin resistance and hyperinsulinemia by separating a sample of 81 subjects into 4 subgroups according to quartiles of insulin sensitivity (SI) (measured with the minimal model of an intravenous glucose tolerance test) and baseline insulin. Results show that (1) values of SI within the upper quartile are associated with low ηb due to low ηp ; (2) low SI regardless insulinemia is associated with increased aggregation indexes; (3) when low SI is associated with hyperinsulinemia (insulin the upper quartile and SI in the lower) there is a further increase in ηb due to an increase in ηp ; (4) neither SI nor insulinemia modify Hct. Thus hyperinsulinemia and insulin resistance induce hyperviscosity syndromes which are somewhat different, although they are associated most of the time. Low SI increases RBC aggregation while hyperinsulinemia increases ηp . Show more

Keywords: Insulin resistance, insulin sensitivity, minimal model, metabolic syndrome, hemorheology, plasma viscosity, erythrocyte aggregability

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 113-119, 2006

Authors: Williams, P.R. | Hawkins, K. | Wright, C. | Evans, A. | Simpkin, H. | Barrow, M.S. | Williams, R.L.

Article Type: Research Article

Abstract: The rheological behaviour of coagulating human blood has been measured using multiple strain wave frequencies. The results indicate that coagulating blood, prior to the point of incipient clot formation, can be modelled by a modified form of the Gross–Marvin ‘ladder’ model, and the benefits of such modeling for blood coagulation are discussed.

Keywords: Rheology, blood coagulation, discrete relaxation spectra

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 123-127, 2006

Authors: Savov, Y. | Antonova, N. | Zvetkova, E. | Gluhcheva, Y. | Ivanov, I. | Sainova, I.

Article Type: Research Article

Abstract: Whole blood viscosity (WBV) and hematometric indices of erythrocytes as red blood cell count (RBC), mean erythrocyte volume (MCV), hemoglobin (HGB), hematocrit (HCT), mean hemoglobin content of erythrocytes (MCH), HGB/HCT values (MCHC) and red blood cell distribution width (RDW) have been studied in a group of 15 chronic opioid addicts under methadone maintenance therapy with mean age 26.53±7.34 years. WBV elevation and changes in MCV, HGB, HCT, RDW were found in intravenous drug users compared to healthy individuals. As well, RBC was decreased leading to an increase in MCH and MCHC values. Correlation analysis suggested that the correlation among the …RBC, HGB, HCT and WBV was the closest. Heroin macrocytosis (heroin macrocytic anemia) was established, related with the increased RDW in chronic heroin abusers. The results are in accordance with data revealing abnormal effects of alcohol and other drugs on whole blood rheology and hematometric/morphometric characteristics of erythrocytes. Show more

Keywords: Whole blood viscosity, erythrocyte hematometric indices, chronic heroin abusers, heroin macrocytosis (heroin macrocytic anemia)

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 129-133, 2006

Authors: Konstantinova, Elena | Ivanova, Lilia | Tolstaya, Tatiyana | Mironova, Elena

Article Type: Research Article

Abstract: The results of some researches specify the important role of blood rheological properties changes in arterial hypertension (AH) pathogenesis. The goal of our study is to investigate the parameters of hemorheology and platelet aggregation in patients with various grade of AH. The study was carried out on 27 patients with grade 1 AH (group 1), 24 patients with grade 2 AH (group 2) and 29 healthy subjects (group 3). In patients of these groups, we evaluated erythrocytes deformability, red blood cells and platelets aggregation, blood and plasma viscosity. Using intra-vital computer-associated microscopic system we investigated microcirculation of bulbar conjunctiva. We …observed that the rate of ADP-induced platelets aggregation is higher in group 1 as compared to groups 2 and 3. In groups 1 and 3, red blood cells rigidity index is significantly lower as compared to group 2. Erythrocyte aggregability is higher in group 2 in comparison with groups 1 and 3. The results obtained demonstrate that mild hypertension is associated with the rise of platelets aggregability, moderate hypertension is accompanied by the reduction of red blood cells deformability and increase of erythrocyte aggregability. These data may reflect differences in conditions for the formation of microcirculation disorders in AH of various grade. Show more

Keywords: Arterial hypertension, platelets, erythrocytes, deformability, aggregation, microcirculation

Citation: Clinical Hemorheology and Microcirculation, vol. 35, no. 1-2, pp. 135-138, 2006