Blood is thicker than water: the management of hyperviscosity in adults with cyanotic heart disease

Complications of chronic hypoxia, including erythrocytosis, hyperviscosity, abnormalities of hemostasis, cerebral abscesses, stroke, and endocarditis, are among the most common consequences of cyanotic heart disease in adults. The compensatory erythrocytosis of cyanotic heart disease can become pathologic by causing an increase in blood viscosity, thereby decreasing perfusion and resulting in decreased total oxygen delivery and increased risk of venoocclusive/hyperviscosity syndrome. Treatment of hyperviscosity secondary to erythrocytosis in cyanotic heart disease is controversial. Data is limited but suggest that phlebotomy has the potential to increase exercise capacity, reduce the symptoms of hyperviscosity, and reduce the potential risk of vasoocclusive disease in selected patients with polycythemia secondary to cyanotic heart disease. Unfortunately, repeated phlebotomy can quickly lead to iron deficiency, resulting in microcytic erythrocytes that induce higher viscosity than normocytic erythrocytes, which may increase the risk for venoocclusive events. There are limited data on the use of hydroxyurea to suppress erythrocytosis in this patient population. The authors conclude that until newer approaches to decreasing hematocrit without inducing iron deficiency are shown to be safe and efficacious, phlebotomy should only be used for the acute resolution of hyperviscosity symptoms. In addition, the use of hydroxyurea should be limited to patients with recurrent symptoms.     

Is whole body impedance a predictor of blood viscosity?

Bioelectrical impedancemetry (BIA) has received a widespread interest as a non-invasive approach to body fluid volumes. Since similar techniques have been studied to assess in vitro rheological properties of blood, we investigated the relationships between whole body impedance and blood viscosity parameters in order to determine possible predictive equations. 30 sportsmen (24.6+/-1.01 years; 73.96+/-1.62 kg; 177.73+/-1.33 cm) were enrolled into the study. Body composition was assessed with a multifrequency bioelectrical impedancemeter (Dietosystem Human IM Scan) using low intensity at the following frequencies: 1, 5, 10, 50 and 100 kHz. Viscometric measurements were done at 1000 s(-1) with a falling ball viscometer (MT 90 Medicatest). Hematocrit (Hct) was measured with microcentrifuge. A standardized exercise test was performed on a cycloergometer during 25 minutes. Physical working capacity (W170) was calculated and VO2max was evaluated with Astrand nomograms. Two hemorheological parameters were independently correlated with impedance (Z) measurements: whole blood viscosity (WBV) at 100 kHz (r=0.518; p=0.01) and Hct at 1 kHz (r=-0.485; p=0.01). Plasma viscosity was correlated multilinearly with water/fat free mass and Z at 10 kHz (r=0.441; p=0.02). In addition both WBV and Z at 100 kHz exhibited correlations with aerobic working capacity (VO2max ) with r=-0.482 and r=-0.475 (p相似文献   

Thrombus in Right Ventricular Outflow Tract: Unique Cause of Refractory Cyanotic Spell

Iron deficiency state in patients with cyanotic congenital heart disease can mimic as well as aggravate hyperviscosity symptoms. Correction of iron deficiency in these cases is expected to improve symptoms. We report an unexpected occurrence of refractory cyanotic spell in a child with tetralogy of Fallot due to thrombus in right ventricular outflow tract following intravenous iron sucrose therapy.     

Correlation between retinal microcirculation and blood viscosity in patients with hyperviscosity syndrome

Hyperviscosity syndrome leads to vascular disturbances in different organs. In the retina typical ophthalmoscopic changes can be found including dot and blot hemorrhages, retinal and optic nerve head edema, and increased diameter of retinal veins. In this study we examined the retinal microcirculation in patients with hyperviscosity syndrome. Nineteen patients (14 patients with Waldenstroem's macroglobulinemia, two patients with kryoglobulinemia, three patients with plasmacytoma) were examined. All patients underwent a video fluorescein angiography. In all angiograms the arteriovenous passage time (AVP) and the arm retina time (ART) were quantified. In addition, hematocrit (Hct) and plasma viscosity (ETA) were measured. In patients with hyperviscosity syndrome AVP was significantly prolonged in comparison to healthy volunteers (AVP: 2.5+/-1.3 s vs. 1.5+/-0.4 s; p < 0.01). The ART showed no significant differences. Plasma viscosity was doubled in patients as compared with reference values (ETA: 2.57+/-1.5 mPa s vs. 1.24+/-0.08 mPa s; p < 0.01). In this study we showed an increase in plasma viscosity as well as an increase in arteriovenous passage time. This may result in retinal circulatory disturbances and may cause the typical fundus changes in patients with hyperviscosity syndrome.     

Hydroxyurea therapy for management of secondary erythrocytosis in cyanotic congenital heart disease

Secondary erythrocytosis in cyanotic congenital heart disease (CCHD) causes substantial morbidity because of complications of hyperviscosity, including stroke and chronic end organ damage. Phlebotomy provides temporary improvement but leads to iron deficiency and can actually increase blood viscosity. We describe the successful use of hydroxyurea (hydroxycarbamide) in four patients with uncorrected CCHD and symptomatic secondary erythrocytosis. In all patients, hydroxyurea improved symptoms of hyperviscosity. Substantial decreases in the red blood cell (RBC) count were observed, along with increases in the mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH), leading to only modest declines in the circulating hemoglobin concentration. Two patients experienced transient mild myelosuppression, which promptly resolved with dose reduction of hydroxyurea. Hydroyxurea provides a novel and useful therapeutic approach to reduce hyperviscosity from secondary erythrocytosis in patients with CCHD, while preserving oxygen carrying capacity and avoiding iron depletion by phlebotomy.     

Evaluation of blood rheology in patients with cyanotic congenital heart disease using a microchannel array flow analyzer

Blood hyperviscosity due to secondary erythrocytosis is a common pathologic feature of cyanotic congenital heart disease (CCHD). In CCHD, it is possible that hematological parameters other than red blood cells influence blood rheology. We measured blood passage time to evaluate the blood rheology in patients with CCHD (n=18, age: 15.3+/-11.9 years, mean +/- SD) and age-matched control subjects (n=27) using the microchannel array flow analyzer (MC-FAN), and the results [several hematological parameters, including hematocrit (Hct)] were compared. Blood passage time in the CCHD group was prolonged, compared with the control group (67.6+/-27.2 s vs. 44.6+/-6.7 s). For the CCHD group, blood passage time correlated significantly with red blood cell (RBC) count, hemoglobin (Hb) concentration, Hct, mean corpuscular hemoglobin concentration (MCHC), platelet (Plt) count, high-density lipoprotein cholesterol (HDL-C) level, and triglycerides (TG) level (RBC, r=0.77; Hb, r=0.69; Hct, r=0.73; MCHC, r=-0.64; Plt, r=-0.49; TG, r=0.53; HDL-C, r=-0.49, p<0.05 for each variable). For all 45 subjects, blood passage time correlated significantly with HbA1c level (r=0.45, p<0.01) and tissue-type plasminogen activator (t-PA) antigen level (r=0.46, p<0.01). Our results indicated that blood rheology is reduced in patients with CCHD as expressed by prolonged blood passage time, and it may be defined by several blood parameters in addition to erythrocytosis.     

Adults with cyanotic congenital heart disease: hematologic management

Hematologic management of adults with cyanotic congenital heart disease has received little recent attention. The lack of practical therapeutic guidelines prompted us to consolidate our observations on 124 cyanotic adults for general physicians, cardiologists, and hematologists who care for these patients. Specific attention focused on regulation of erythrocyte mass and concepts of compensated and decompensated erythrocytosis, symptoms of deficient tissue oxygen transport, hyperviscosity and iron deficiency, the potential relation between elevated hematocrit levels and brain injury, hemostasis, urate metabolism, and renal function. Cerebral infarction was not seen in any patient. Phlebotomy is best reserved for treatment of symptomatic hyperviscosity. Iron therapy is indicated for symptomatic iron deficient erythropoiesis. Abnormal hemostatic mechanisms are the rule. Antithrombotic medications have little or no role in treatment. Hyperuricemia is the result of abnormal renal uric acid excretion not urate overproduction, and serves as a marker of abnormal renal function. Drugs that promote urate excretion are the preferred maintenance treatment in symptomatic hyperuricemic patients.     

Blood rheology and body composition as determinants of exercise performance in male soccer players

The aim of this study was to assess on a large series of soccer players our previous reports on blood rheology and exercise performance. In 99 soccer players (Age 24,17 ± 0,42 yr; weight 75,87 ± 0,89 kg; VO2max 46,86 ± 0,95 mL/min/kg) an exercise test was performed for measuring maximal aerobic capacity and we measured blood viscosity at high shear rate (MT90 viscometer) and RBC aggregation (Myrenne MK1). The French questionnaire developped by the consensus group on overtraining of the French Society of Sports Medicine (SFMS) was also employed. The only hemorheologic statistical determinant of VO2max was hematocrit (Hct r = -0.2439; p = 0.0303). The lactate threshold 2 mmol/l was negatively correlated to M1 (r = -0.43224; p = 0.00847). There was a borderline correlation between the overtraining score at the questionnaire of the SFMS and plasma viscosity (r = 0.3080; p = 0.0532). Therefore, our study confirms that aerobic capacity in this sport is negatively correlated to hematocrit, that RBC aggregation is positively associated with blood lactate accumulation in blood during exercise, and that plasma viscosity is one of the parameters that increase when the athlete is on the edge of the overtraining syndrome. These data are consistent with previous reports about soccer players but caution is needed to extrapolate to other sports.     

The effects of iron treatment on viscosity in children with cyanotic congenital heart disease

Objective: This study was planned to determine the effects of iron treatment in children with cyanotic congenital heart disease.

Method and Materials: A total of 39 patients with cyanotic congenital heart disease including 20 (51%) females, 19 (49%) males and whose mean age was 9.9?±?6.2 years, average weight was 33?±?18.4?kg were evaluated. Patients were categorized into two groups as having iron deficiency and no iron deficiency with respect to their ferritin levels. 4?mg/kg/day iron treatment with two valences was applied to the groups with iron deficiency for 3 months. Clinical and laboratory findings of both groups were assessed at the outset and 3 months later and viscosity measurements were carried out.

Results: Iron deficiency was identified in 21 (53.8%) out of 39 patients. Average Hb and Hct values following 3-month iron treatment increased from 14.8?±?2.4?g/dl to 16.0?±?2.0 (P?=?0.003) and from %45.8?±?7.5 to %47.6?±?7.2 (P?=?0.052), respectively. Average viscosity value, however, was 5.6?±?1.0?cP, it reduced to 5.5?±?1.0?cP value by demonstrating very little reduction (P?=?0.741). Nevertheless, O₂ sat value increased from 71.7 to 75% and complaints such as headache, visual blurriness, having frequent sinusitis decreased.

Conclusions: It was observed that iron treatment increased Hb and Hct levels in patients with cyanotic congenital heart disease without raising viscosity and it ensured improvement in clinical symptoms.     

Iron deficiency in a patient with extreme erythrocytosis due to cyanotic congenital heart disease

Erythrocytosis is an adaptive response to improve oxygen transport in cyanotic congenital heart disease (CCHD). However, at highly increased hematocrit levels patients may experience hyperviscosity symptoms. Iron deficiency in CCHD patients is often overlooked due to elevated hemoglobin concentrations. A 29-year-old male with CCHD was readmitted to our outpatient clinic. Red blood cells (11.65*10(12)/L), hemoglobin (25.7 g/dL), and hematocrit (80%) were extremely elevated. Measurements of iron supply showed a constellation typical for iron deficiency with low ferritin (13.2 microg/L), and high sTfR (20 mg/L). We present a case of extremely high red blood cell counts with concomitant iron deficiency. For appropriate management and to avoid misinterpretation of the iron status, ferritin and sTfR should always accomplish laboratory examination of CCHD patients.     

Cyanotic Congenital Heart Disease (CCHD) with Symptomatic Erythrocytosis

Secondary erythrocytosis of cyanotic congenital heart disease (CCHD) is pathologically different from primary erythrocytosis of polycythemia vera (PV). An association between elevated hematocrit and thrombosis has been established in PV patients, and treatment guidelines recommend maintaining hematocrit <45%. Although an association between elevated hematocrit and thrombosis has not been established in CCHD and secondary erythrocytosis, the current clinical practice is to phlebotomize these patients to hematocrit <65%. We report a 21-year-old woman with CCHD who presented with symptomatic erythrocytosis with numbness and tingling with hemoglobin 25.2 g/dl and hematocrit 75.8%. Her symptoms resolved with IV hydration. Other factors, including dehydration and iron deficiency, may precipitate hyperviscosity symptoms. The treatment is volume replacement and low-dose iron therapy, not phlebotomy. Repeated phlebotomy causes iron deficiency with microcytic erythrocytes, which increases the whole blood viscosity and, therefore, can potentially accentuate rather than decrease the risk for a cerebrovascular accident.     

Low hematocrit per blood viscosity ratio as a mortality risk factor in coronary heart disease

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.     

Contribution of blood viscosity in the assessment of flow-mediated dilation and arterial stiffness

Flow-mediated dilation (FMD) is a non-invasive index of endothelial function. In an attempt to standardize FMD for shear stimulus, shear rate (velocity/diameter), rather than shear stress (viscosity*velocity/diameter), is commonly used as a surrogate measure, although it is limited by individual differences in blood viscosity. The purpose of this study was to determine the contribution of whole blood viscosity to FMD and other key measures of vascular function. Blood viscosity, FMD, carotid artery compliance, and carotid-femoral pulse wave velocity (cfPWV) were measured in 98 apparently healthy adults varying widely in age (18-63 years). Whole blood viscosity was not significantly correlated with FMD, cfPWV, or carotid artery compliance. Shear rate was a stronger correlate with FMD than shear stress that takes blood viscosity into account (r = 0.43 vs 0.28). No significant differences were observed between whole blood viscosity and traditional risk factors for cardiovascular disease. Age was positively correlated with cfPWV (r = 0.65, p < 0.001) and negatively correlated with FMD (r = -0.24, p < 0.05) and carotid artery compliance (r = -0.45, p < 0.01). Controlling for viscosity did not reduce the strength of these relations. These results indicate that whole blood viscosity does not significantly impact measures of vascular function and suggests that the common practice to use shear rate, rather than shear stress, in the adjustment of FMD is valid.     

Aggregability and disaggregability of erythrocytes in women suffering from ovarian cancer: evidence for an increased disaggregation threshold

In order to further characterize the alterations of erythrocyte aggregation described in ovarian cancer, we measured it with laser backscattering in eleven women suffering from ovarian cancer (mean age: 44.7 +/- 3.6, extreme values: 28-61 yr) compared with thirteen matched control women. Blood rheology exhibited a wide variability in cancer patients, with some unusually high values of plasma viscosity and/or RBC aggregation in individual cases. The only significant differences were found for the RBC disaggregation threshold which was higher in patients than in controls (78.06 +/- 10.14 vs 52.6 +/- 3.15 s(-1), p < 0.05), while hematocrit was lower (34.45 +/- 1.42 vs 38.23 +/- 0.75, p < 0.05). A negative correlation between hematocrit and corrected blood viscosity on the whole sample of subjects (r = 0.454, p < 0.05) indicates that hematocrit is decreased in subjects prone to high viscosity, resulting in similar values of apparent blood viscosity in controls and patients. Thus, a lower disaggregability of RBCs is evidenced in women with ovarian cancer, as well as a tendency to blood hyperviscosity compensated by a reduction of hematocrit which suggests that there may be some degree of 'viscoregulation'.     

Intravenous iron alone for the treatment of anemia in patients with chronic heart failure.

OBJECTIVES: This study was undertaken to assess the hematologic, clinical, and biochemical response to intravenous iron in patients with chronic heart failure (CHF) and anemia. BACKGROUND: Anemia is common in patients with CHF and is associated with higher morbidity and mortality. The combination of erythropoietin (EPO) and iron increases hemoglobin (Hb) and improves symptoms and exercise capacity in anemic CHF patients. It is not known whether intravenous iron alone is an effective treatment for anemia associated with CHF. METHODS: Sixteen anemic patients (Hb < or =12 g/dl) with stable CHF (age 68.3 +/- 11.5 years, 12 men, 9 participants New York Heart Association [NYHA] functional class II and the remainder class III, left ventricular ejection fraction 26 +/- 13%) received a maximum of 1 g of iron sucrose by bolus intravenous injections over a 12-day treatment phase in an outpatient setting. Mean follow-up was 92 +/- 6 days. RESULTS: Hemoglobin rose from 11.2 +/- 0.7 to 12.6 +/- 1.2 g/dl (p = 0.0007), Minnesota Living with Heart Failure (MLHF) score fell (denoting improvement) from 33 +/- 19 to 19 +/- 14 (p = 0.02), 6-min walk distance increased from 242 +/- 78 m to 286 +/- 72 m (p = 0.01), and all patients recorded NYHA class II at study end (p < 0.02). Changes in MLHF score and 6-min walk distance related closely to changes in Hb (r = 0.76, p = 0.002; r = 0.56, p = 0.03, respectively). Of all baseline measurements, only iron and transferrin saturation correlated with increases in Hb (r = 0.60, p = 0.02; r = 0.60, p = 0.01, respectively). There were no adverse events relating to drug administration or during follow-up. CONCLUSIONS: Intravenous iron sucrose, when used without concomitant EPO, is a simple and safe therapy that increases Hb, reduces symptoms, and improves exercise capacity in anemic patients with CHF. Further assessment of its efficacy should be made in a multicenter, randomized, placebo-controlled trial.     

Haemorheological abnormalities in arterial hypertension and their relation to cardiac hypertrophy

Haemorheological characteristics were measured in a group of 52 patients with essential arterial hypertension (HT), and were compared with those of a group of normotensive subjects. The relationships between the arterial blood pressure (BP), the echocardiographic indices of left ventricular hypertrophy (LVH), and the haemorheological measurements, were studied. The group of hypertensive patients was found to have a hyperviscosity syndrome with significant elevations of blood viscosity at all shear rates (for gamma = 0.20/s, 29.6 +/- 0.6 versus 28.0 +/- 0.3 mPa.s, P less than 0.01: for gamma = 128/s, 4.2 +/- 0.05 versus 4.1 +/- 0.02 mPa.s, P less than 0.02, of plasma viscosity (1.29 +/- 0.01 versus 1.22 +/- 0.06 cSt, P less than 0.001); of erythrocyte aggregation index (17.8 +/- 0.06 versus 14.6 +/- 0.4, P less than 0.001); of erythrocyte filterability index (13.3 +/- 0.5 versus 8.8 +/- 0.2, P less than 0.001) and plasma fibrinogen level (3.4 +/- 0.9 versus 2.8 +/- 0.6 g/l, P less than 0.02). The haematocrit did not differ from that of normotensive subjects (43.3 +/- 0.6 versus 44.7 +/- 0.5%, NS). The left ventricular mass was increased and was positively correlated with the blood viscosity at a high shear rate (r = 0.38, P less than 0.01) and with the erythrocyte aggregation index (r = 0.47, P less than 0.01). Systolic, diastolic, and mean arterial blood pressures were positively correlated with the left ventricular mass (r = 0.34-0.47, P less than 0.05) and with the erythrocyte aggregation index (r = 0.42-0.46, P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of iron deficiency on tissue oxygen delivery in cyanotic congenital heart disease

To test the hypothesis that tissue oxygen delivery would be affected by diminished oxygen stores in cyanotic congenital heart disease, serum ferritin, transferrin saturation, hemoglobin, red cell mean corpuscular volume (MCV), red cell 2,3-diphosphoglycerate (DPG), P50, blood gases, oxygen saturations and systemic oxygen transport were measured in 29 hypoxemic infants and children. For the group, aortic saturation was 81 +/- 9%, PaO2 was 50 +/- 12 mm Hg, hemoglobin 16.2 +/- 2.1 gm/dl and systemic oxygen transport 620 +/- 145 ml/min/m2. P50 was increased above normal values (28.8 +/- 2.3 vs 26.6 +/- 1.1 mm Hg, p less than 0.01), and DPG was 2.35 +/- 0.54 mumol/ml, at the upper limits of normal for this assay. Iron deficiency was present in 8. When patients with P50 greater than or equal to 30 mm Hg and P50 less than 30 mm Hg were compared, iron stores were diminished in the high P50 group: [serum ferritin (19 +/- 8 vs 53 +/- 48 ng/ml, p = 0.0006), transferrin saturation (11 +/- 6 vs 23 +/- 11%, p = 0.003) and MCV (79 +/- 8 vs 86 +/- 4 fl, p = 0.05)]. Hemoglobin, aortic oxygen saturation, PaO2 and systemic oxygen transport were similar in both groups. In children with iron sufficiency, 15 of 21 had MCV greater than 90th percentile for age and sex (p less than 0.001 versus expected distribution). Also, MCV greater than 90th percentile for age and sex had a positive predictive value of 0.88 for iron sufficiency. This study demonstrates that diminished iron stores in cyanotic congenital heart disease are associated with a more right-shifted oxyhemoglobin dissociation curve (increased P50).(ABSTRACT TRUNCATED AT 250 WORDS)     

Is the feeling of heavy legs in overtrained athletes related to impaired hemorheology?

The feeling of having "heavy legs" (FHL) is commonly reported in the overtraining syndrome (OTS), i.e., the condition wherein an athlete is training excessively, yet performance deteriorates. Since FHL is also a sign of chronic venous insufficiency where it can be corrected by rheo-active drugs, and given the fact that OTS is also a hemorheologic disease associated with mild hemoconcentration, we investigated whether the FHL is associated with a hemorheologic profile. 37 athletes training 13.05+/-0.97 hr/week completed the French questionnaire of Overtraining (mean score: 11.66+/-1.96) and underwent a medical check-up including hemorheological measurements. 14 subjects quote the item: "I have the FHL". Although well matched with the 23 others for age and body composition, FHL subjects had higher plasma viscosity (1.44+/-0.05 vs 1.32+/-0.02 mPa.s; p<0.05) and a higher red cell aggregation as measured with laser backscattering (Affibio indices: final aggregation time "TF": 36.77+/-1.88 vs 44.26+/-2.37; p<0.05; aggregation index at 10 s "S10": 26.31+/-1.14 vs 21.92+/-1.19; p<0.05). The OTS score was correlated positively with plasma viscosity (r=0.549; p=0.008), whole blood viscosity (r=0.4458; p=0.03), and the following aggregability parameters: "S10" (r=0.4818; p=0.0232) and the aggregation index at 60 s "S60" (r=0.4601; p=0.0312). The OTS score was also correlated negatively with the aggregability parameters "TF" (r=-0.4432; p=0.0389) and the initial aggregation time "TA" (exponential relationship r=-0.458; p=0.03). These findings suggest that the feeling of heavy legs in overtrained athletes is related to OTS-related hemorheologic disturbances, namely mild plasma hyperviscosity and mild erythrocyte hyperaggregability.     

Extension of equations for predicting viscosity parameters with whole body bioelectrical impedance to a sedentary population

In a previous paper we determined predictive equations for predicting viscosity parameters with whole body Bioelectrical impedance (BIA) in athletes. We have tried to extend this analysis to a sedentary population. 36 sedentary obese or insulin resistant patients (40.36+/-2.30 years; 85.77+/-3.54 kg; 165.93+/-1.56 cm) were enrolled into this study. Body composition was assessed with a multifrequency bioelectrical impedancemeter Dietosystem Human IM Scan that uses low intensity at the following frequencies: 1, 5, 10, 50 and 100 kHz. Analysis was performed with the software Master 1.0 that gives the choice among 25 published equations for body composition calculation. Viscometric measurements were done at 1000 s(-1) with a falling ball viscosimeter (MT 90 Medicatest). Hematocrit was measured with microcentrifuge. Two hemorheological parameters were independently correlated with impedance (Z) measurements at 50 kHz: whole blood viscosity (WBV) (r=0.541, p=0.01) and hematocrit (Hct) (r=-0.686, p=0.01). New equations slightly different from those we report in the previous paper were found. These findings confirm our previous reports of relationships between whole body electric properties and factors of blood viscosity in athletes and allow the use of BIA to a sedentary population. Obviously, extension of this study will be needed to determine if BIA can be used to generalize predictive equations in both sedentary and trained individuals.