Clinical Hemorheology and Microcirculation - Volume 38, issue 1

Authors: Jung, F. | Mrowietz, C. | Rickert, D. | Hiebl, B. | Park, J.W. | Franke, R.P.

Article Type: Research Article

Abstract: Echinocyte formation is associated with a rigidification of the cells that possibly affects capillary diffusion and, consequently, the tissue's oxygen supply. This study examines how many echinocytes appeared after the addition of various concentrations of radiographic contrast media (RCM) (Iodixanol 320, Iohexol 350, Iopromide 370, Iomeprol 350 and Iomeprol 400 mg Iodine/ml) compared to red blood cells in isotonic saline solution as well as in autologous plasma. Isotonic saline solution, Iodixanol, Iohexol, Iomeprol 350, Iomeprol 400 and Iopromide in concentrations of 10%, 20% or 40% were added to the plasma of six healthy subjects. Subsequently, the erythrocytes were resuspended …in these RCM/plasma mixtures, incubated for 5 minutes at 37°C and then examined under the microscope. The various mixtures and concentrations of the RCM in the mixture all had a significant effect on the number of discocytes (p<0.0001). The percentage of discocytes for all concentrations significantly depended on the RCM/plasma mixture (p=0.0097). Of all the RCM/plasma mixtures used as well as of the NaCl/plasma mixtures, the Iodixanol/plasma mixture showed the most similar discocyte fraction compared to red blood cells in the autologous plasma. At the same time, while Iodixanol in this respect differed from all other RCMs, the other RCMs only differed little from one another with respect to the discocyte fraction. Show more

Keywords: Radiographic contrast media, echinocyte, Iodixanol, Iohexol, Iopromide, Iomeprol

Citation: Clinical Hemorheology and Microcirculation, vol. 38, no. 1, pp. 1-11, 2008

Authors: Connes, Philippe | Tripette, Julien | Chalabi, Tawfik | Beltan, Eric | Etienne-Julan, Maryse | Chout, Roger | Hue, Olivier | Hardy-Dessources, Marie-Dominique

Article Type: Research Article

Abstract: We compared routine coagulation markers in six sickle cell trait carriers ((SCT, or AS hemoglobinopathy) – the heterozygous form of sickle cell anemia) and six subjects with normal hemoglobin before and after a prolonged and intense exercise. Blood was sampled at rest and at the end of the entire exercise test to measure coagulation markers (prothrombin time, activated partial thromboplastin time, plasma fibrinogen and antithrombin III activity), hematocrit (Hct) and yield stress (τy ). Results obtained at the end of exercise were corrected by the percent change in plasma volume. Blood coagulation markers, Hct and τy were not different …between the two groups at rest. Exercise did not change prothrombin time, antithrombin III activity and plasma fibrinogen, decreased activated partial thromboplastin time and increased Hct and τy in the two groups. These parameters were not significantly different between the two groups at the end of exercise, except for plasma fibrinogen which was slightly higher in SCT carriers but in the normal range values. The results have been discussed in relation with some cases of exercise-related sudden death in SCT carriers, reported in several studies. Therefore our results show that the increased risk for clinical complications in certain SCT carriers during exercise seems to be unrelated to higher blood coagulation activity. Show more

Keywords: Sickle cell trait, coagulation, fibrinogen, exercise

Citation: Clinical Hemorheology and Microcirculation, vol. 38, no. 1, pp. 13-21, 2008

Authors: Vayá, Amparo | Murado, Julián | Santaolaria, Marisa | Simó, María | Micó, Luisa | Calvo, Javier | Todolí, José | Ricart, Jose M.

Article Type: Research Article

Abstract: Atherothrombotic events are significant factors of mortality and morbidity in patients with systemic lupus erythematosus (SLE). The extent that rheological factors may be involved in these events in these patients has not been established. We measured the following rheological parameters in 86 patients with SLE, of whom 16 had suffered venous and/or arterial thrombotic events, and in 86 healthy controls: fibrinogen (Fbg), plasma viscosity (PV), blood viscosity at 230 s−1 both at native haematocrit (BVn 230 s−1 ) and corrected to 45% (BVc 230 s−1 ), erythrocyte aggregation at stasis (AE0 ) and at 3 s−1 (AE1 ), …aggregation time (Ta), aggregation index at 10 s (AI10 ), disaggregation threshold (γD), and erythrocyte deformability (ED). In addition glucose, total cholesterol (T-Chol), triglycerides (TG), haematocrit (Hct) and Body Mass Index (BMI) were determined. SLE Disease Activity Index (SLEDAI) was also assessed. The patients showed a significant increase in BMI (P=0.030), TG (P<0.001), PV (P=0.007), AE0 (P=0.005), AE1 (P=0.006), AI10 (P=0.024), γD (P=0.001), Fbg (P=0.050); and a significant decrease in Ta (P<0.001), Hct (P<0.001) and BVn 230 s−1 (P=0.003). When patients with SLEDAI<or>10 were compared, the latter had lower Hct (P=0.041) and lower BVn 230 s−1 (P=0.017) than those with less SLEDAI. No significant differences were found in any of the parameters analysed on comparing patients who had suffered a thrombotic event with those who had not. Our results suggest that, although patients with SLE have moderate rheological changes, these do not seem to be responsible for the increase in the thrombotic tendency in these patients. Show more

Keywords: Haemorheology, systemic lupus erythematosus, thrombosis

Citation: Clinical Hemorheology and Microcirculation, vol. 38, no. 1, pp. 23-29, 2008

Authors: Prantl, L. | Schmitt, St. | Gais, S. | Tsui, T.Y. | Lamby, P. | Babilas, P. | Nerlich, M. | Kubale, R. | Zorger, N. | Herold, T. | Feuerbach, S. | Jung, E.M.

Article Type: Research Article

Abstract: This article has been retracted. The updated version of the article has been published in Clinical Hemorheology and Microcirculation Volume 38(2), 2008, pp. 105-118: http://iospress.metapress.com/content/t1h1758752451257/.

Citation: Clinical Hemorheology and Microcirculation, vol. 38, no. 1, pp. 31-44, 2008

Authors: Tschopp, Marcel | Reinhart, Walter H.

Article Type: Research Article

Abstract: Platelet primary hemostatic function occurs under high shear conditions. Cyclooxyenase inhibitors such as ibuprofen inhibit this platelet aggregation under high shear rates only to a limited extent. This prompted the present study on 10 healthy volunteers treated with 100 mg aspirin for 4 weeks. The platelet function analyser (PFA-100® ) was used to measure the closure time (CT) of a membrane pore coated with collagen and epinephrine by aggregating platelets under shear rates of 5000–6000 s−1 . A first dose of 100 mg aspirin prolonged the CT above the normal range in 4 of 10 individuals, but the CT for …the whole group (153±42 s) was not different from baseline (112±18 s). After 7 and 28 days of treatment, CTs were >300 s in 8 individuals and the mean values for the group were significantly higher than baseline. However, one subject had an intermediate response and one had an aspirin non-responsiveness, which was not overcome by 300 mg aspirin daily. The CT was normalized in 4 individuals 48 h after the last aspirin dose and in 7 individuals after 72 h, when the mean value for the group became not different from baseline. We conclude that the platelet function measured with the PFA-100 is not inhibited significantly after a single dose of 100 mg aspirin, is thereafter inhibited consistently in the majority, but not all individuals during a 4 week treatment, and returns to normal in 48–72 h. Since large interindividual differences exist, monitoring of platelet inhibition at the beginning of an aspirin treatment should be considered and validated in a prospective study. Show more

Keywords: Aspirin, platelets, platelet aggregation

Citation: Clinical Hemorheology and Microcirculation, vol. 38, no. 1, pp. 45-50, 2008

Authors: Kenyeres, P. | Juricskay, I. | Tarsoly, P. | Kesmarky, G. | Mühl, D. | Toth, K. | Bogar, L.

Article Type: Research Article

Abstract: Increased blood viscosity has not been associated with mortality risk in coronary heart disease (CHD). We aimed to investigate the predictive power of hematocrit per blood viscosity (Hct/BV) ratio as a marker of rheological oxygen carrying capacity of the blood to assess mortality risk of CHD. Elective coronary angiography was performed and CHD was proved in 109 patients in 1996 and 1997. In 78 cases (72%) complete follow up information was obtained in February 2006. During the follow up time (mean 8.9 years) 10 patients died due to cardiac cause (group C). Two patients died due to non-cardiac cause and …66 were still alive at the end of the follow up period (group NC, n=68). Mean hematocrit per blood viscosity (Hct/BV) ratio was significantly lower in group C comparing to NC (87±5; 93±9 Pa−1 s−1 , SD, respectively, p=0.022). Other factors (body mass index, serum cholesterol, fibrinogen, hematocrit, plasma and blood viscosity, cardiac index, left ventricular ejection fraction) provided no statistical differences. Kaplan–Meier survival analysis showed only the impact of fibrinogen and Hct/BV ratio on cardiac mortality (p=0.029 and 0.009, respectively). Receiver operating characteristic curves proved only Hct/BV ratio to be able to differentiate between groups (area under curve: 0.716, p=0.028). Hct/BV ratio showed significant negative correlation with the frequency of hospital admissions (r=−0.377, p=0.03). Low Hct/BV ratio can be regarded as a risk factor of cardiac death in CHD. Show more

Keywords: Hematocrit, blood viscosity, fibrinogen, coronary heart disease, plasma viscosity

Citation: Clinical Hemorheology and Microcirculation, vol. 38, no. 1, pp. 51-56, 2008

Authors: Salazar Vázquez, Beatriz Y. | Salazar Vázquez, Miguel A. | Venzor, Verónica Covarrubias | Negrete, Adolfo Chávez | Cabrales, Pedro | Díaz, Jesús Sida | Intaglietta, Marcos

Article Type: Research Article

Abstract: In this study we determine the effects of reducing blood glucose on mean arterial blood pressure (MAP) and hematocrit (Hct) in patients with type 2 diabetes who are not responding to conventional treatment in an intensive treatment program 1 year after initiation of treatment. Data on MAP, glucose and Hct was obtained from 21 diabetic type 2 individuals subjected to personalized treatment and compared (paired statistics) to pretreatment conditions. Exclusion criteria were severe retinopathy, diabetic nephropathy, amputation of diabetic foot and increased glucose > 50 mg/dl. Treatment was the combined administration of glibenclamide and metformin dosed to obtain a reduction …of glucose levels. Exercise and strict adherence to a prescribed diet were prescribed in all cases. One year after initiation of therapy, glucose decreased from 219±87 to 158±51 mg/dl (p<0.002), Hct increased from 41.6±3.2 to 44.7±2.9% (p<0.001) and MAP decreased from 100.6±11.0 to 94.3±7.2 mmHg (p<0.001). There were no statically significant changes in cholesterol and triglyceride concentrations. The patients lost weight (72.5±12.6 to 70.3±13.0 kg, p<0.001) and lowered blood creatinine concentration from 1.04±0.24 to 0.95±0.25 mg/dl, p<0.05. The increase in Hct should correspond to an increase in blood viscosity of about 12%, however blood pressure, and presumably vascular resistance, decreased by 6%. It is proposed that these effects are in part related to improved kidney function resulting in increased Hct and blood viscosity which increases vascular wall shear stress and NO bioavailability leading to a vasodilator effect. Show more

Keywords: Diabetes treatment, blood pressure, hematocrit, nitric oxide, glycemic control, kidney function, blood viscosity

Citation: Clinical Hemorheology and Microcirculation, vol. 38, no. 1, pp. 57-64, 2008