Clinical Hemorheology and Microcirculation - Volume 39, issue 1-4

Article Type: Other

DOI: 10.3233/CH-2008-1067A

Citation: Clinical Hemorheology and Microcirculation, vol. 39, no. 1-4, pp. 1-2, 2008

Article Type: Other

DOI: 10.3233/CH-2008-1067B

Citation: Clinical Hemorheology and Microcirculation, vol. 39, no. 1-4, pp. 3-4, 2008

Article Type: Other

DOI: 10.3233/CH-2008-1067C

Citation: Clinical Hemorheology and Microcirculation, vol. 39, no. 1-4, pp. 5-5, 2008

Article Type: Other

DOI: 10.3233/CH-2008-1115

Citation: Clinical Hemorheology and Microcirculation, vol. 39, no. 1-4, pp. 7-8, 2008

Authors: Ramping, Michael W.

Article Type: Other

DOI: 10.3233/CH-2008-1063

Citation: Clinical Hemorheology and Microcirculation, vol. 39, no. 1-4, pp. 9-20, 2008

Authors: Park, J.-W. | Leithäuser, B. | Vršansky, M. | Jung, F.

Article Type: Research Article

Abstract: Background: Exercise electrocardiography is an imperfect test for the detection of coronary artery disease (CAD). Magnetocardiography detects cardiac electrical disturbances associated with myocardial ischemia. We prospectively investigated the accuracy of high-dose dobutamine stress magnetocardiography (DS-MCG) and simultaneous electrocardiography (DS-ECG) for the detection of significant CAD. Methods: 100 patients with an intermediate pre-test probability for CAD underwent DS-MCG using a multichannel magnetometer prior to invasive coronary angiography. Patients were examined at rest and during a standard dobutamine–atropine scheme. Significant reduction of epicardial current strength/density during stress, reconstructed from the magnetic field map and superposed on a virtual heart model indicates …myocardial ischemia. A 12-lead DS-ECG was recorded simultaneously. Significant coronary artery stenosis was defined as ≥70% of lumen reduction. Results: Without β-blocker all 100 patients reached the targeted heart rate. The image quality of DS-MCG and DS-ECG was sufficient for analysis in all patients. In 19 patients CAD was ruled out angiographically. Thirty two or seven patients revealed coronary artery stenoses of 30–49% or of 50–69%, respectively. In 42 patients we found significant stenoses of ≥70%. In 41 of these patients DS-MCG revealed myocardial ischemia. The sensitivity of DS-MCG and DS-ECG for the detection of significant coronary artery stenosis was 97.6% and 26.2%, the specificity of DS-MCG and DS-ECG 82.8% and 82.8%, respectively. Conclusions: DS-MCG can be performed with a standard dobutamine/atropine stress protocol. DS-MCG yields a significantly higher accuracy for the detection of significant coronary artery stenosis than DS-ECG. Show more

Keywords: Magnetocardiography, electrocardiography, coronary artery disease, dobutamine stress test

DOI: 10.3233/CH-2008-1064

Citation: Clinical Hemorheology and Microcirculation, vol. 39, no. 1-4, pp. 21-32, 2008

Authors: Zorio, Esther | Murado, Julián | Arizo, David | Rueda, Joaquín | Corella, Dolores | Simó, María | Vayá, Amparo

Article Type: Research Article

Abstract: The role played by hemorheological alterations on acute myocardial infarction (AMI) in young patients remains a question of debate. We have carried out a case-control study of 84 AMI patients aged <45 years and 135 sex and age matched controls, in which blood viscosity (BV), plasma viscosity (PV), erythrocyte aggregation (EA) performed with the Myrenne (EA0, EA1) and the Sefam aggregometer (Ta, AI10, γD), erythrocyte deformability (ED) along with fibrinogen (Fbg), C-reactive protein (CRP) and plasmatic lipids i.e. total cholesterol (T-Chol) and triglycerides (TG) were determined. AMI patients showed higher, Fbg, TG, EA0, EA1, IA10, γD and lower Ta than …controls (p=0.029, p<0.001, p=0.013, p=0.003, p=0.010, p=0.025) respectively. No differences in the other rheological parameters were observed. No differences in any rheological parameter were observed regarding the AMI type, number and score of stenosed vessels and the time elapsed since the thrombotic event. After multivariate adjustment, Fbg>380 ml/dl and TG>185 ml/dl were independently associated with a higher risk of erythrocyte hyperaggregability (OR: 5.5 CI 95% 1.04–29.27 and OR: 7.3 CI 95% 2.66–20.03) respectively. EA>8.85 was associated with a increased AMI risk (OR: 5.3 CI 95% 1.98–14.5). These results reinforces the view that in young AMI patients increased Fbg and TG may promote the development of ischaemic events not only through its known mechanism but also by altering rheological blood behaviour, mainly increasing EA. Show more

Keywords: Acute myocardial infarction, haemorheology, erythrocyte aggregation

DOI: 10.3233/CH-2008-1065

Citation: Clinical Hemorheology and Microcirculation, vol. 39, no. 1-4, pp. 33-41, 2008

Authors: Lee, Byoung K. | Durairaj, Azhil | Mehra, Anilkumar | Wenby, Rosalinda B. | Meiselman, Herbert J. | Alexy, Tamas

Article Type: Research Article

Abstract: The pathophysiological abnormalities of stable angina (SA) and acute coronary syndromes (ACS) may, in part, be promoted by fluid forces associated with local blood flow and hence by the rheological properties of blood. This study evaluated several hemorheological parameters in 16 healthy controls and in 16 SA, 18 unstable angina (UA) and 19 acute myocardial infarct (AMI) patients; all patients underwent diagnostic angiography following blood sampling. Rheological measurements included whole blood viscosity, plasma viscosity and RBC aggregation via erythrocyte sedimentation rate (ESR) and Myrenne aggregometer indices. Compared to controls, RBC aggregation was significantly elevated in all patient groups (p<0.001), with …the rank being AMI>UA>SA. RBC aggregability as tested in 70 kDa dextran exceeded control in all patients. Blood viscosity values calculated at 40% Hct, plasma viscosity and yield shear stress values followed the same pattern (AMI>UA>SA>control); increases of inflammatory markers (i.e., WBC count, hs-CRP) were elevated in all patient groups in the order AMI>UA>SA. Our study thus indicates an association between hemorheological abnormalities and the severity of coronary artery disease, and suggests the merit of evaluating whether therapeutic interventions that normalize blood rheology may reduce the incidence and/or progression of coronary artery disease. Show more

Keywords: Stabile angina, acute coronary syndrome, blood rheology

DOI: 10.3233/CH-2008-1066

Citation: Clinical Hemorheology and Microcirculation, vol. 39, no. 1-4, pp. 43-51, 2008

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

Article Type: Research Article

Abstract: A group of 15 chronic opioid addicts (DA) with mean age 26.5±7.3 years was studied by means of a rotational Contraves Low Shear 30 viscometer and the results have been compared with a control group of 19 healthy subjects. It was found that the mean whole blood viscosity values of the investigated group of heroin abusers (n=15) were elevated compared to that of healthy persons (n=19) over the whole shear rate range and fell by more than ten orders of magnitude (Savov et al., 2006). The present investigation uses the coefficients of the models of Ostwald-de-Walle (power law) and Herschel–Bulkley …law, which describe whole blood flow curves (τ−γ) within the shear rates range from 10−2 to 102 s−1 and itself incorporate whole blood viscosity data in the entire shear rate range. A significant difference in the mean yield shear stress τ0 values of the drug abusers' group compared to the controls was found. A strong positive linear correlation was determined between the parameters of RBC aggregation in the group of heroin addicts confirming our previous results (Ivanov and Antonova, 2005; Savov, Zvetkova et al., 2007; Savov, Antonova et al., 2007) for intensive RBC and platelet aggregation and morphological changes in DA group. Show more

Keywords: Chronic heroin addicts, whole blood rheology, power law and Herschel–Bulkley law, yield shear stress, RBC aggregation

DOI: 10.3233/CH-2008-1068

Citation: Clinical Hemorheology and Microcirculation, vol. 39, no. 1-4, pp. 53-61, 2008

Authors: Antonov, P. | Antonova, M. | Nikolova, N. | Antonova, N. | Vlaskovska, M. | Kasakov, L.

Article Type: Research Article

Abstract: Viscoelastic characteristics (VEC) of old rat aorta (Wistar, 10 months) were obtained by sinusoidal excitation of intraluminal pressure (p) in cylindrical arterial preparations. The pressure excitation frequency (fexc ) was swept in the range 3–30 Hz up and down at several mean-pressure levels while response volume oscillations were recorded and resonance curves were plotted. Natural frequency (f0 ), dynamic modulus of elasticity (E′) and coefficient of viscosity (β) were estimated from resonance curves and the dependences of VEC on p were drawn. The results showed that f0 decreased linearly with p whereas our previous data for young rat aorta …(Wistar, 4 months) showed independence of f0 on p. E′ increased nonlinearly with p with the values being higher in comparison to young rat aorta. This means stiffening of rat aorta with age in accordance with the known literature data. β-values increased linearly with p being higher in comparison to young rat aorta, demonstrative of raised intrinsic friction in the wall. VEC values were higher at decreasing fexc suggesting that the direction of excitation sweeping also determines the arterial wall biomechanical behaviour. It could be concluded that blood vessels VEC worsen with age, which endangers the arterial wall integrity, especially at higher intraluminal pressure. Show more

Keywords: Arterial blood vessels, forced oscillations, resonance curve, natural frequency, dynamic modulus of elasticity, coefficient of viscosity

DOI: 10.3233/CH-2008-1069

Citation: Clinical Hemorheology and Microcirculation, vol. 39, no. 1-4, pp. 63-68, 2008