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Cardiovascular effects of doping drugs are numerous, with different mechanisms: vasoconstriction of amphetamines, erythropoietin and cocaine; sodium water retention of anabolic steroids and corticosteroids; elevation in blood viscosity of erythropoietin, perflurocarbon emulsion, recombinant hemoglobin and anabolic steroids; sympathetic nervous system activation of amphetamines, beta 2 agonists and clenbuterol; lipids profile disorder of anabolic steroids. Physical activity consequences, particularly bradycardia and dehydration, are worsening. Thrombosis and arrythmogenic effects, with possibility of sudden death, are the severe immediate events. Hypertension and coronary diseases are medium-term effects; acute myocardial infarction is frequent. Heart failure can be secondary to cardiac muscle direct fibrosis, like with anabolic steroids. These cardiovascular effects are serious and it is necessary to early detect the doping drugs use in sporstmen; all prescribing physician should be aware of existing drugs and their clinical events.

Objective: To date, the treatment of priapism in sickle-cell patients has relied on measures aimed at lowering blood viscosity and acidosis and reducing the level of circulating hemoglobin S (hyperhydration, alkalinization, or exsanguinotransfusion...) Surgical cavernous-venous shunt may be proposed if conservative treatment fails. We examined the efficacy of intracavernous etilefrin injections., Patients and Methods: From January 1996 through October 1997 (20 months) we performed 35 consecutive intracavernous injections of an alphastimulant, etilefrin in 7 sickle-cell patients (6 SS, 1 AS) who had experienced one or several episodes of low-flow priapism lasting 2 to 28 hours., Results: Involution of the tumefaction was rapidly achieved in all cases. Tolerance was satisfactory, although some post-injection undesirable effects were reported by certain patients: moderate transient pain (2-5 min) in the retrosternal area, or intense pain in the penis (more intense than the priapism) which lasted 10 to 30 minutes. This work confirmed the earlier reported efficacy of intracavernous injections of etilefrin and suggests that the autonomous nervous system plays an important role in the genesis of this condition in sickle-cell patients. Patients should be informed about the observed undesirable effects which have not been reported previously in the literature., Conclusion: Etilefrin can be proposed as first line treatment for priapism in sickle-cell patients (at least in cases lasting less than 24 h). The pathogenic mechanism could involve neuromuscular dysfunction.

The objective was to investigate in vivo the rheological effects of plasma substitutes (fluid gelatin, dextran 40, dextran 60, hydroxyethylstarch). The study was performed during a hypervolemic hemodilution in 60 adult volunteers who underwent an odontological surgery. Two control groups were infused with Ringer-Lactate or 4% human albumin. Each patient was infused with 500 ml of plasma substitute or control fluid. Blood samples were obtained at four different times: prior to (t0) and immediately after (t1) the infusion, then 3 hours (t2) and 24 hours (t3) after the hemodilution. At t1 and t2, plasma viscosity did not present important variations, except for the group infused with dextran 60 where a significant increase in plasma viscosity was observed. Blood viscosity and erythrocyte aggregation measurements were performed at hematocrit 40% to determine the intrinsic properties of substitute and eliminate the effects of hemodilution. Blood viscosity at high shear rates underwent minor variations in all groups. In contrast, blood viscosity at low shear rate and aggregation parameters exhibited important variations which markedly depended on the used substitute. The infusion of Ringer-Lactate, albumin and dextran 40 induced a significant decrease in blood viscosity and in erythrocyte aggregation. With dextran 60 and gelatin, blood viscosity and erythrocyte aggregation increased. Finally, the infusion with hydroxyethylstarch did not present important differences as compared to the results recorded at t0. Twenty for hours after the infusion, it should be noted an increase in plasma fibrinogen, probably due to surgery, which caused an increase in erythrocyte aggregation in all groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Beta-blockers have been shown to have a beneficial effect especially regarding secondary prevention in coronary patients. The reduction in global mortality is most noticeable with respect to sudden death, which suggests an antiarrhythmic effect, but other non-lethal ischaemic events are also less frequent. The explanation of this observation is certainly multifactorial: some results point to a potential action on the development of atherosclerotic lesions. This justifies experimental and clinical studies of this hypothesis with this pharmacological group of drugs.

It is now well established that blood behaves like a non Newtonian fluid varying with the shear rate. Blood viscosity pattern relative to various shear rates shows a high viscosity at low shear rate (due to rouleau formation or erythrocyte aggregation) with a decrease at high shear rate. This high blood viscosity will be of a great importance only while pathological blood flowing with low output or stasis. Pathological variations of one factor determining blood viscosity and clinical signs define hyperviscosity syndrome. From an hemodynamical point of view, the appearance of an hyperviscosity syndrome, may, as a result of feedback mechanism, aggravate the disorders leading to a slowing down and even to a stop in local blood flow, subsequently encouraging ischemia. Moreover hyperviscosity also leads to a theoretical lowering capacity of oxygen transport by blood approximatively in proportion with the haematocrit/blood viscosity ratio. With regard to therapeutic aspect, the pharmacology of rheological influence drugs must be displaced into the wider outline proposed by Virchow. So we could distinguish between therapeutic action of drugs upon haematocrit, plasmatic proteins level, red blood cell deformability and erythrocyte aggregation. Among this last category disaggregating effect of rutosides has been first pointed out by Schmid-Schöenbein and Col. Our results of an in vitro study of troxerutine effect with ranging concentrations from 10(-5) to 10(-2) M upon blood viscosity and erythrocyte aggregation are reported.

We realized a double-blind randomized study in 26 pregnant with clinical symptoms of lower limbs venous insufficiency. Both groups were similar and received either (n = 12) troxerutine (4 g/day) or placebo (n = 14), during 30 days. Evaluation at J0 and J30 was both clinical and rheological by mean of Myrenne aggregometer. After blood shear rate of 600 s-1, two parameters were determined: M after roughly stopping shear rate, M1 after diminishing to shear rate of 3 s-1. Results exhibited steady values in patients receiving troxerutine while a significant increasing values in patients receiving placebo for the two parameters M and M1. That result in erythrocyte antiaggregating action of troxerutine, hence lowering viscosity action, in venous insufficiency during pregnancy.

Recombinant human erythropoietin (rhu EPO) is the choice treatment of dialytic anemia; however, this therapy has side effects due to the increased number of blood components involved. It seemed to us worth assessing, by hemorheological study, the impact of such a treatment on blood flow properties, already impaired in this type of patients. This study was designed to measure the evolution of hemorheological parameters in 16 hemodialysed patients before and after 2.3 and 6 months of treatment with rhu EPO. Hemorheological work-ups included: erythrocyte filtration with a hemorheometer; blood and plasma viscosities (LS30), ATP and 2.3 DPG, RBC aggregation (Sefam erythroaggregameter), RBC morphology under a scanning electron microscope; blood counts and full biochemical work-ups were performed to explore renal function. The results showed, besides a significant increase in hemoglobin: normalized rigidity index, reflecting the better deformability of erythrocytes; a moderate increase in blood viscosity with uncorrected hematocrit, becoming significant after 6 months of treatment. This increase however did not reach the values that could be expected with the increased hematocrit (it was probably balanced by improved erythrocyte deformability, which is confirmed by the fact that with corrected hematocrit, blood viscosity decreases during treatment). Studying erythrocyte aggregation in hemodialysed patients reveals, in the absence of any treatment, a decrease in aggregation time and a higher dissociation threshold, which reflects a tendency to erythrocyte hyperaggregation enhanced by erythropoietin.(ABSTRACT TRUNCATED AT 250 WORDS)

A study was carried out to assess the changes induced by an infusion of dextran, molecular weight 60,000 daltons, in blood and urine. Plasma and urine dextran and serum protein concentrations, haematocrit, blood and urine viscosities, and blood oncotic pressure were measured in 10 consecutive male patients. Fifteen min after administration of 20 ml dextran 1000 (Promit), they were each given 500 ml (30 g) dextran 60 (Hemodex) over 30 min for plasma volume expansion. The measurements were carried out at the end of the infusion, and then at regular intervals over a 48 h period. The highest dextran blood concentrations were found at the end of the infusion, decreasing thereafter with a distribution half-life of 1.83 +/- 0.64 h, and an elimination half-life of 25.5 +/- 7.6 h. Haematocrit values decreased by 12%, and serum protein concentrations by 9.5%, after the end of the infusion. These changes remained significant for 9 h; they were probably due to the dilution effect of 500 ml of dextran. Colloid osmotic pressure was not significantly altered (20.7 +/- 4.7 mmHg vs. 23.1 +/- 5.1 mmHg 48 h after the end of the infusion). The colloid osmotic pressure due to dextran 60 compensated for the fall in protein concentration. A decrease in blood viscosity was found at different shear rates, despite dextran 60 being highly viscous. This could also be explained by a dilution effect. The highest degree of urinary excretion occurred 30 min after the end of the infusion, and lasted for 3 h. Forty-five percent of the total dextran dose had been excreted by the 48th hour.(ABSTRACT TRUNCATED AT 250 WORDS)

The current situation concerning the use of Streptokinase in the treatment of recent myocardial infarction does not make it possible to draw any definite conclusions with regard to its therapeutic value:--mortality would not appear to be significantly modified in the majority of series;--the occurrence rate of major complications during the acute phase is not notably altered but it seems possible that the electrocardiographic course of the necrosis is more favourable under the influence of Streptokinase when treatment is begun early. The long term course cannot be assessed. Finally, it is certain that the tolerance of Streptokinase therapy has been good in all the published series. In particular, Streptokinase does not appear to have been associated with severe haemorrhagic complications nor a higher prevalence of cardiac rupture.

A study of blood viscosity at 3 rates of determination (0.232-0.348 and 1.16 sec-1) in insulin-dependent diabetic subjects controlled by artificial pancreas, shows a reduction in this parameter after 30 hours of feed back control. The relationship between these variations, the mechanical cohesion of the agglutinated red cells, and the deformability of these structures are discussed.

The complexity of the mechanisms which enter into play in the phenomenon of erythrocyte sedimentation have for long aroused the curiosity of research workers. A simultaneous study of this parameter and of the viscosity, of the relative zeta potential together with the osmotic fragility, led us to appreciate the respective actions of three isolated plasma proteins : albumin, immunoglobuin G, fibrinogen, on the ESR and on the rheological properties of the red cell.

Blood has particular rheological properties which partly condition its flow, especially in capillary vessels, and its ability to deliver oxygen. It is not subject to gravitation, pseudoplastic, thixotropic and visco-elastic. Blood viscosity depends upon macroscopic factors, such as erythrocyte aggregation and deformability. Hyperviscosity is observed in cases of increased haematocrit (polycythaemia and relative polycythaemia), increased serum proteins and changes in protein balance (e.g. rise in fibrinogen and immunoglobulins, fall in albumin) as seen in inflammation and dysglobulinaemia, drop in temperature (hypothermia), increased erythrocyte aggregation (shock, fat embolism) or imparied deformability due to various acquired or inherited disorders of red cell membrane or cytoplasma (e.g. sickle cell anaemia, renal failure, hyperlipoproteinaemias, thrombosis, diabetes). The various factors may be combined, as in diabetes. Conversely, hypoviscosity may result from decreased haematocrite, fall in blood proteins and fibrinogen, or hyperthermia. Hyperviscosity can be corrected by acting on its various constituents. Treatments include haemodilution, plasmapheresis, anti-aggregants and drugs improving red cell deformability.

Between March 85 and November 86, 20 patients underwent treatment for sudden deafness [19] or bilateral tinnitus [1] by Pentoxifylline (1 200 mg/24 Hrs, including 400 mg IV over 24 Hrs) and Carbogen sessions (2 or 3/24 Hrs), during six days on an in-patient basis, followed by 1 200 mg/24 Hrs orally during another eight days. The results, assessed by clinical examination, audiometry, and erythrocyte filtration time (using the Reid and Dormandy method) on the first, sixth, and fourtheenth days, were: -- good or very good a little more than 75%, -- moderate: 5%, -- poor: a little fewer than 20%. Filtration times in a group of asymptomatic patients, determined by the same method, were used as a reference.

The treatment of retinal thrombosis is an unresolved problem, mainly because of the numerous factors which participate in their formation; modifications in the walls of veins and arteries, external compressions, changes in the blood count--particularly of the platelets--slowing down of the blood flow, increase in blood viscosity etc. No drug provides constant results. Some widely employed drugs such as vasodilators may be useless or even contra-indicated. Emphasis is placed on anti-coagulants, fibrinolytics, antiaggregating agents and methods of lowering blood viscosity. Their action is difficult to test objectively. Some do appear to be useful, especially in cases of central vein thrombosis. Thrombi of branches of the central vein are apparently inacessible to medical therapy, but occasionally improvement is seen after laser coagulation. This seems to apply also to hemorrhagic glaucoma secondary to retinal obstruction.

In a previous study the authors proposed a law of visco-elasticity with three parameters to describe the influence on blood of a forced test according Couette's schedule. The changes produced by different plasma substitutes are studied under equilibrium conditions and under altered conditions. Marked changes were noted in the various parameters. It would appear that these changes are related to the cohesion of erythrocyte rouleaux.

Hemodilution during E.C.C. is into use for more than 15 years. Its interest is obvious (blood economy, beneficient action on viscosity, prevention of "sludging"), but opinions are different concerning the best level of hemodiultion. The authors defend the notion of a moderate dilution (hematocrit larger than or equal to 25 p. 100) required to maintain a high perfusion pressure. For atherosclerotic patients, they describe the hemodilution technics tried on more than 4,000 cases since 1964. The advantages of hemodilution concern on one hand the diminution or the disparition of drawbacks and complications due to the obtainment and to the administration of homologous blood and on the other hand the beneficient intrinsical effects of the blood dilution on the tissular perfusion. In convenients are those due to changes in the concentration of sodium, chlore and specially potassium which may be responsible of serious cardiac arrythmias. Because of increasing difficulties concerning the use of homologous blood (obtaining difficulties and complications relative to its use), the authors consider the utilization of autologous blood taken off before the operation on the patient and freezed.