The effect of medical clowning on reducing pain, crying, and anxiety in children aged 2-10 years old undergoing venous blood drawing--a randomized controlled study.

UNLABELLED: Recently, the utilization of medical clowns to reduce anxiety, stress, and even pain associated with hospitalization has become popular. However, the scientific basis of this benefit and outcome is scant. Venipuncture and IV cannulation are very common sources of pain in ill children. To reduce pain, one common approach is to apply a local anesthetic prior to the procedure. In the current study, we sought to compare the utilization of medical clowning in this process with two control groups: (1) local anesthetic cream (EMLA®, Astrazeneca, London, UK) applied prior to the procedure (active control) and (2) the procedure performed with neither clown nor EMLA (control group). We hypothesized that a medical clown will reduce pain, crying, and anxiety in children undergoing this procedure.Children aged 2-10 years who required either venous blood sampling or intravenous cannulation were recruited and randomly assigned to one of the three groups. Outcome measures consisted of the duration of the whole procedure (measured objectively by an independent observer), the duration of crying (measured objectively by an independent observer), subjective assessment of pain level (a commonly used validated scale), and anxiety level regarding future blood exams (by questionnaire). Analysis of variance (ANOVA) was used to compare between the groups. p < 0.05 was considered statistically significant.One hundred children participated. Mean age was 5.3 ± 2.5 years (range 2-10 years). The duration of crying was significantly lower with clown than in the control group (1.3 ± 2.0 vs 3.8 ± 5.4 min, p = 0.01). With EMLA, this duration was 2.4 ± 2.9 min. The pain magnitude as assessed by the child was significantly lower with EMLA than in the control group (2.9 ± 3.3 vs 5.3 ± 3.8, p = 0.04), while with clown it was 4.1 ± 3.5, not significant when compared with the other two modalities. Hence, duration of crying was shortest with clown while pain assessment was lowest with EMLA. Furthermore, with clown duration of cry was significantly shorter than in controls, but pain perception did not significantly differ between these groups. As expected, the duration of the entire process was shortest in the control group (5.0 ± 3.8 min), moderate with clown (19.3 ± 5.8 min), and longest with EMLA (63.2 ± 11.4 min, p < 0.0001 between all). Parental reporting of a beneficial effect was greater with clown than with EMLA (3.6 ± 0.8 vs 3.0 ± 1.1, p = 0.02). Parental assessment of child's anxiety related to future blood tests as evaluated by telephone the following day revealed that it was significantly lower with clown than in the control group or EMLA (2.6 ± 1.2 vs 3.7 ± 1.3 or 3.8 ± 1.6, p < 0.01 for both). CONCLUSIONS: Distraction by a medical clown is helpful in children undergoing blood tests or line insertion. Although pain reduction was better with EMLA, both duration of cry and anxiety were lower with a medical clown. These results strongly encourage and support the utilization of medical clowns while drawing blood in children.

Altered fibrin architecture is associated with hypofibrinolysis and premature coronary atherothrombosis.

OBJECTIVE: Hypofibrinolysis promotes atherosclerosis progression and recurrent ischemic events in premature coronary artery disease. We investigated the role of fibrin physical properties in this particular setting. METHODS AND RESULTS: Biomarkers of recurrent thrombosis and premature coronary artery disease (CAD) were measured in 33 young post-myocardial infarction patients with angiographic-proven CAD and in 33 healthy volunteers matched for age and sex. Ex vivo plasma fibrin physical properties were assessed by measuring fibrin rigidity and fibrin morphological properties using a torsion pendulum and optical confocal microscopy. The fibrinolysis rate was derived from continuous monitoring of the viscoelastic properties after addition of lytic enzymes. Young CAD patients had a significant increase in plasma concentration of fibrinogen, von Willebrand factor, plasminogen activator inhibitor type 1, and lipoprotein(a) as compared with controls (P<0.05). Fibrin of young CAD patients was stiffer (P=0.002), made of numerous (P=0.002) and shorter fibers (P=0.04), and lysed at a slower rate than that of controls (P=0.03). Fibrin stiffness was an independent predictor for both premature CAD and hypofibrinolysis. CONCLUSIONS: This first detailed study of clot properties in such a group of patients demonstrated that abnormal plasma fibrin architecture is an important feature of both premature CAD and fibrinolysis rate. The determinants of this particular phenotype warrant further investigation.

Hemoglobin Pitie-Salpetriere beta 34 (B16) Val replaced by Phe. A new high oxygen affinity variant associated with familial erythrocytosis.

Hemoglobin Pitie-Salpetriere was detected by routine isoelectric focusing. It moved up on isoelectric focusing between hemoglobin A and hemoglobin F, near Hb F. On cellulose acetate strips at pH 8.6, it moved as hemoglobin A. This new variant exhibits a high oxygen affinity associated with familial erythrocytosis. The valine residue in position beta 34 has been replaced by a phenylalanine residue. This residue is involved in the alpha 1 beta 1 contact.

Percutaneous coronary intervention after subcutaneous enoxaparin pretreatment in patients with unstable angina pectoris.

BACKGROUND: Subcutaneous low-molecular-weight (LMW) heparins can effectively replace unfractionated heparin in patients with unstable angina or non-Q-wave myocardial infarction. However, the optimal anticoagulation strategy for these patients when they require cardiac catheterization is still unclear. Therefore, we evaluated a new and simple strategy of anticoagulation in these patients. METHODS AND RESULTS: A total of 451 consecutive patients with unstable angina/non-Q-wave myocardial infarction were treated for at least 48 hours with subcutaneous injections of enoxaparin (1 mg [100 IU]/kg every 12 hours, cycled at 6 AM and 6 PM). Of this unselected population, 293 patients (65%) underwent a coronary angiography within 8 hours of the morning LMW heparin injection, followed by immediate percutaneous coronary intervention (PCI) in 132 patients (28%). PCI was performed without any additional bolus of unfractionated/LMW heparin and without coagulation monitoring. Anti-Xa activity at the time of catheterization was 0.98+/-0.03 IU/mL, was >0.5 IU/mL in 97.6% of patients, and did not relate to the LMW heparin injection-to-catheterization time. There were no in-hospital abrupt closures or urgent revascularizations after PCI. The death/myocardial infarction rate at 30 days was 3.0% in the PCI group (n=132) but 6.2% in the whole population (n=451) and 10.8% in the patients not undergoing catheterization (n=158). The 30-day major bleeding rate was 0.8% in the PCI group, which was comparable to that of patients without catheterization (1.3%). CONCLUSIONS: PCI within 8 hours of the last enoxaparin subcutaneous injection seems to be safe and effective. The safety of subcutaneous LMW heparin in combination with platelet glycoprotein IIb/IIIa blockade awaits further study.

Anti-Xa activity relates to survival and efficacy in unselected acute coronary syndrome patients treated with enoxaparin.

BACKGROUND: Low-molecular-weight heparin (LMWH) is recommended in the treatment of unstable angina (UA)/non-ST-segment-elevation myocardial infarction (NSTEMI), but no relationship has ever been shown between anticoagulation levels obtained with LMWH treatment and clinical outcomes. METHODS AND RESULTS: In all, 803 consecutive patients with UA/NSTEMI were treated with subcutaneous enoxaparin and were followed up for 30 days. The recommended dose of enoxaparin of 1 mg/kg BID was used throughout the population except when physicians decided on dose reduction because of a history of a recent bleeding event or because of a high bleeding risk. Anti-factor Xa activity was >0.5 IU/mL in 93% of patients; subtherapeutic anti-Xa levels (<0.5 IU/mL) were associated with lower doses of enoxaparin. The 30-day mortality rate was significantly associated with low anti-Xa levels (<0.5 IU/mL), with a >3-fold increase in mortality compared with the patients with anti-Xa levels in the target range of 0.5 to 1.2 IU/mL (P=0.004). Multivariate analysis revealed low anti-Xa activity as an independent predictor of 30-day mortality at least as strong as age, left ventricular function, and renal function. In contrast, anti-Xa activity did not predict major bleeding complications within the range of anti-Xa levels observed in this study. CONCLUSIONS: In this large unselected cohort of patients with UA/NSTEMI patients, low anti-Xa activity on enoxaparin treatment is independently associated with 30-day mortality, which highlights the need for achieving at least the minimum prescribed anti-Xa level of 0.5 IU/mL with enoxaparin whenever possible.

Acute release of plasminogen activator inhibitor-1 in ST-segment elevation myocardial infarction predicts mortality.

BACKGROUND: A few studies have suggested that von Willebrand factor (vWF) or plasminogen activator inhibitor-1 (PAI-1) can be associated with outcomes of acute coronary syndromes. The present study was designed to assess the acute release of these markers in ST-segment elevation myocardial infarction (STEMI) and their relations to death. METHODS AND RESULTS: In 153 consecutive patients with STEMI, vWF and PAI-1 antigens were measured on admission (H0) and 24 hours later (H24). At 30 days, the death rate was 7.2%. Heart failure (Killip stage > or =3) on admission was present in 13.7% of patients. The acute release of PAI-1 (H24-H0, in ng/mL) and of vWF (H24-H0, in %) was dramatically higher in patients who died than in those who survived (46.9+/-26.3 versus -0.6+/-2.8 ng/mL, P=0.0001 and 65.8+/-20.0% versus 10.0+/-5.1%, P=0.004 for PAI-1 and vWF, respectively) and in patients developing heart failure compared with those without (24.8+/-10.1 versus -1.1+/-3.3 ng/mL, P=0.004 and 47.3+/-11.0% versus 8.1+/-5.6%, P=0.005 for PAI-1 and vWF, respectively). The release of PAI-1 correlated weakly with the left ventricular ejection fraction (R=-0.195, P=0.01) and the peak of troponin (R=0.149, P=0.045). Postangioplasty TIMI-3 flow and the acute release of PAI-1 were the only 2 independent predictors of death at 30 days. CONCLUSIONS: The acute release of vWF and PAI-1 over the first 24 hours of STEMI is associated with death and heart failure. The acute rise of PAI-1 is also a strong independent predictor of death at 30 days.

Effects of various anticoagulant treatments on von Willebrand factor release in unstable angina.

OBJECTIVES: We tested the hypothesis that different anticoagulant treatments may produce different platelet effects and von Willebrand factor (vWf) release in unstable angina. BACKGROUND: The early increase of vWf has been reported to be a risk factor for adverse outcome in unstable angina. Anticoagulant drugs play a key role in stabilization of unstable angina, but they may not have the same efficacy and the same effects on acute vWf release. METHODS: We studied 154 patients enrolled in several clinical trials testing four different anticoagulant treatments in unstable angina or non-Q-wave myocardial infarction. Patients were treated during at least 48 h by either intravenous unfractionated heparin, one of two different low molecular weight heparins (enoxaparin or dalteparin) or the direct thrombin inhibitor PEG-hirudin. All patients received aspirin but no Ib/IIIa inhibitors. RESULTS: The release of vWf over the first 48 h (delta vWf) did not relate to the baseline clinical characteristics. At 30 days of follow-up, delta vWf was sevenfold higher in patients with an end point (death, myocardial infarction, revascularization) than in patients free of events (+53 +/-7% vs. +7 +/-14%, p = 0.004). The same trend was present for each component of the composite end point with the highest levels for one-month mortality (+87 +/- 32% vs. +26 +/- 8%, p = 0.09). The vWf values did not increase over 48 h in patients receiving either enoxaparin or PEG-hirudin (+10 +/- 9% and -5 +/- 20%, respectively). A serious rise ofvWf was measured in unfractionated heparin-treated patients (+87 +/- 11%), which differed significantly from the enoxaparin group (p = 0.0006) and PEG-hirudin group (p < 0.0001). In dalteparin-treated patients, delta vWf was elevated (+48 +/- 8%) and did not differ from the unfractionated heparin group (NS). CONCLUSIONS: We confirm that, in unstable angina patients, a rise of vWf over the first 48 h is associated with an impaired outcome at 30 days. Moreover, the four different anticoagulant treatments tested here do not provide the same protection with regards to vWf release, which may have important prognostic implications and explain different results observed in recent clinical trials.

[Anticoagulants and dental extractions]. / Anticoagulants et extractions dentaires.

Dental extractions in patients under platelet antiaggregant or anticoagulant therapy pose the problem of risk benefit between stopping or carrying on treatment. The difficulties of reequilibrating the INR after a heparin relay have led surgeons and cardiologists to look for alternative solutions. Different means of local haemostasis using products with haemostatic properties or not, or the use of sutures or glues, have given encouraging results but there is too much uncertainty for systematic recommendations to practicians responsible for dental extractions in these patients. The authors propose a technique which has the advantages of associating systematically different methods, making bleeding complications very unusual, without interrupting anticoagulant or antiaggregant therapy.

Components of the fibrinolytic system are differently altered in moderate and severe hypothyroidism.

T(4) levels are determinant of several components of the fibrinolytic system. However, relationships between hypothyroidism and alteration of fibrinolytic capacity are not well established, and published data remain conflicting. As the impact of hypothyroidism on both degradation and synthesis of proteins may vary according to the severity of the disease, we measured fibrinolytic activity across varying states of hypothyroidism. We measured fibrinogen, D-dimers (DDI), alpha(2)-antiplasmin activity, tissue plasminogen activator antigen (t-PA Ag), plasminogen, plasminogen activator inhibitor antigen (PAI-1 Ag), and factor XII (FXII) of the coagulation. We prospectively included 76 middle-aged female subjects: 25 controls, 24 patients displaying moderate hypothyroidism (TSH, 10--50 mU/L), and 27 patients with severe hypothyroidism (TSH, >50 mU/L). Blood pressure, body mass index, smoking habits, total cholesterol as well as high and low density lipoprotein subfractions, triglyceride, fasting glycemia, and insulinemia were recorded. We found a different pattern of fibrinolytic abnormalities according to the severity of hypothyroidism. Compared with controls, patients with moderate hypothyroidism displayed a decreased fibrinolytic activity, as reflected by lower DDI levels, higher alpha(2)-antiplasmin activities, and higher levels of t-PA and PAI-1 Ag. In sharp contrast, patients with severe hypothyroidism exhibited higher DDI levels, lower alpha(2)-antiplasmin activities, and lower t-PA and PAI-1 Ag levels. These results were not accounted for by confounding factors such as age, smoking, and components of the insulin resistance syndrome. Free T(4) was significantly associated with fibrinogen, alpha(2)-antiplasmin, PAI-1 Ag, total cholesterol, and triglyceride and was negatively associated with DDI. The main hypotheses underlying the mechanisms by which thyroid status may affect the fibrinolytic system remain to be established. In conclusion, patients with moderate hypothyroidism, who were consistently shown to be at high risk for cardiovascular disease, have decreased fibrinolytic activity. Subjects with severe hypothyroidism have a tendency toward increased fibrinolytic activity, and these modifications may participate to the bleeding tendency observed in such patients.

Population pharmacokinetic-pharmacodynamic analysis of fluindione in patients.

OBJECTIVE: Fluindione is a vitamin K antagonist with a long half-life. This study was designed to investigate the pharmacokinetics and pharmacodynamics of multiple doses of fluindione in patients. METHODS: In a learning group of 49 patients who began fluindione treatment, blood samples were taken 12, 18, or 24 hours after one, three, and five doses. Concentration of fluindione, activity of clotting factors II, VII, IX and X, prothrombin complex activity (PCA), and international normalized ratio (INR) were measured. An indirect-response pharmacodynamic model was used for each effect. A comprehensive analysis was performed with a nonparametric population approach. The model was evaluated in 24 other patients: blood samples were taken 24 hours after two, three, four, and six doses; and PCA and INR were observed. RESULTS: Analysis of concentrations and clotting factor activities showed notably that (1) fluindione has a long half-life (median, 69 hours), and (2) concentration that inhibits the synthesis of the clotting factors by 50% varied for each factor, with a median ranging from 0.25 to 2.05 mg.L-1 for factors VII and II, respectively. The results obtained for INR and PCA were validated in the 24 subsequent patients. CONCLUSION: The population approach allowed the comparison of several pharmacodynamic submodels. This first application of the indirect-response model to multiple oral anticoagulant doses in patients confirmed that both the pharmacokinetics and the pharmacodynamics of fluindione show substantial interindividual variability.

Subcutaneous enoxaparin with early invasive strategy in patients with acute coronary syndromes.

BACKGROUND: Subcutaneous enoxaparin during at least 48 hours provides adequate anticoagulation and good clinical results in patients with non-ST-segment elevation acute coronary syndromes undergoing percutaneous coronary intervention (PCI). METHODS: In this nonrandomized retrospective study, we compared 347 patients with non-ST-segment elevation acute coronary syndromes who underwent rapid PCI after only 2 injections of subcutaneous enoxaparin (EI, n = 117) to those referred later to the catheterization laboratory with >or=3 injections (DI, n = 230). We measured anti-Xa at the time of PCI and evaluated bleeding and major ischemic events (death/myocardial infarction) at 30 days. RESULTS: Patients in the EI group more frequently received glycoprotein IIb/IIIa inhibitors and clopidogrel preceding PCI than did patients in the DI group (58.1% vs 31.7%, P <.0001 for glycoprotein IIb/IIIa inhibitors and 68.4% vs 40.4% for clopidogrel pretreatment, P <.0001, respectively). The anti-Xa activity measured at the time of catheterization (0.92 +/- 0.04 U/mL vs 0.96 +/- 0.02 U/mL, EI vs DI, P =.25) and the injection-to-catheterization times (5.6 +/- 0.2 h vs 5.2 +/- 0.1 h, EI vs DI, P =.17) were similar in both groups. The 30-day bleeding rates of 1.7% and 4.8% in the EI and DI strategies were found to be equivalent with a significant non-inferiority test for the EI strategy (P <.05). There was a nonsignificant trend for less death or myocardial infarction at 30 days in the EI group compared to the DI group (4.3% vs 7.0%, non-inferiority test not significant). CONCLUSION: A rapid invasive strategy with only 2 subcutaneous injections of enoxaparin provides similar levels of anticoagulation, and is associated with a favorable trend for ischemic events and with safety equivalent to a more prolonged "upstream" treatment with enoxaparin.

Relation between plasminogen activator inhibitor-1 and hepatic enzyme concentrations in hyperlipidemic patients.

Plasminogen activator inhibitor type-1 (PAI-1) is a key determinant of the fibrinolytic capacity. Its activity correlates with most of the characteristic features of insulin resistance syndrome, i.e. obesity, high blood pressure and hyperlipidemia. We measured plasma PAI-1 antigen levels in 131 asymptomatic men (aged 44.2 +/- 11 years) who had been referred for hyperlipidemia. Those taking medication and those with a secondary hyperlipidemia were excluded. We confirmed the correlation between PAI-1 levels and the following variables: body mass index, blood pressure, triglyceride concentration, and blood glucose and insulin levels before and after an oral glucose tolerance test. We also found a significant and independent correlation between PAI-1 and the concentration of the hepatic enzymes glutamyl transferase, alanine aminotransferase and aspartate aminotransferase. Mild liver abnormalities (presumably steatosis) may thus be one of the factors accounting for high plasma PAI-1 levels in hyperlipidemic patients.

Relationship between thyroid hormones and plasma D-dimer levels.

High serum levels of cholesterol and triglycerides are risk factors for coronary heart disease and are strongly related to several haemostatic parameters. Thyroid disorders are a frequent feature in hyperlipidemic patients and are also associated with a variety of haemostatic abnormalities. Therefore, we analysed the relationships between free T4 (fT4) levels and Factor VII and VIII activities (FVIIc and FVIIc), D-Dimers (DDI) and Plasminogen Activator Inhibitor type 1 (PAI-1), in a group of 472 healthy patients referred for hyperlipidemia. Fourty patients were found to have primary hypothyroidism. A negative correlation was found in the whole study population between fT4 and DDI (p = 0.0001, r = -0.21) and the same results were found after exclusion of the patients with fT4 below the normal range (p = 0.0007, r = -0.17). In a multivariate regression analysis, the relationship between DDI and fT4 was independent of age, Body Mass Index (BMI), gender and total cholesterol. Less impressive correlation coefficients were found with FVIIc (r = -0.10), FVIIIc (r = -0.09) and PAI-1 (r = -0.09). These results suggest that fT4 may play a physiological role in the regulation of the haemostatic equilibrium in hyperlipidemic patients and that low levels of fT4 are associated with a hypercoagulable state.

Effect of prior exposure to Chlamydia pneumoniae, Helicobacter pylori, or cytomegalovirus on the degree of inflammation and one-year prognosis of patients with unstable angina pectoris or non-Q-wave acute myocardial infarction.

Inflammation and chronic infections may be important features in the pathogenesis of acute coronary syndromes. We describe 6 systemic markers of inflammation in patients with unstable angina or non-Q-wave myocardial infarction and the relations between these markers, seropositivity to chronic infections, and prognosis. C-reactive protein (CRP), serum amyloid A protein (SAA), fibrinogen, interleukin-6 (IL-6), neopterin, procalcitonin, and serum antibody levels to Chlamydia pneumoniae, Helicobacter pylori, and cytomegalovirus were measured on admission and 48 hours later. One-year clinical follow-up was performed. Plasma levels of acute phase reactants were all elevated on admission and increased further at 48 hours: CRP from 10.1 +/- 2.1 mg/L at baseline to 26.6 +/- 5.1 mg/L at 48 hours (p <0.001); SAA from 27.3 +/- 8.5 to 93.1 +/- 23.2 mg/dl (p <0.005); fibrinogen from 3.2 +/- 0.1 to 3.8 +/- 0.1 g/L (p <0.0001); whereas initial high levels of IL-6 tended also to increase from 9.8 +/- 2 to 15.3 +/- 3.1 pg/ml (p = NS). In contrast, neopterin and procalcitonin remained unchanged. We found no association between levels of each inflammatory marker and the serologic status. Furthermore, levels of inflammatory proteins in patients seronegative to all 3 agents were comparable to those of patients seropositive to 2 or 3 infectious agents. The composite end points of death, myocardial infarction, recurrent angina, or revascularization at 1-year follow-up did not differ according to the serologic status. Thus, in patients with acute coronary syndromes, the acute phase proteins increased over the first 2 days of hospitalization. This initial inflammatory reaction as well as the 1-year clinical outcome did not differ according to the initial serologic status of Chlamydia pneumoniae, Helicobacter pylori, or cytomegalovirus.

Alterations in natural anticoagulant levels during allogeneic bone marrow transplantation: a prospective study in 27 patients.

The natural anticoagulants (antithrombin III, protein C, protein S), plasminogen and tissue plasminogen activator antigen (t-PA ag), were measured in 27 consecutive patients following allogeneic BMT. Thrombosis and veno-occlusive disease were not seen in this study. Changes in the levels of these proteins occurred mainly during acute GVHD. There were 14 patients who had no acute GVHD (group I) and 13 patients who had acute GVHD (group II). No changes in antithrombin III (ATIII), protein C, protein S and t-PA levels were found in group II before the appearance of acute GVHD when compared with group I. However, we noted a significant rise in protein S (p = 0.01), antithrombin III (p = 0.001) and t-PA ag (p = 0.0004) levels during acute GVHD. In contrast, protein C levels decreased early in GVHD (p = 0.005), and then increased progressively over the course of a month post-GVHD. No changes in plasminogen levels were observed. These results might reflect activation of and/or damage to endothelial cells during GVHD.

Elevated total plasma homocysteine, a risk factor for thrombosis. Relation to coagulation and fibrinolytic parameters.

Homocystinuria is a rare inherited metabolic disease. Arterial and venous thromboembolic events represent frequent and life-threatening complications in homocystinuric patients. It has been suggested that mild homocysteinemia could be a risk factor for vascular disease. We have therefore measured total plasma homocysteine (HCy) concentrations by radioisotopic assay in 50 subjects with venous or arterial thrombosis and studied the relationship between HCy, coagulation and fibrinolytic parameters. Values were considered abnormal if they were higher than 2.7 standard deviations (SD) above the mean, i.e., 14.1 mmol/l. Thus, eighteen of the 50 patients with thrombosis were classified in the hyperhomocysteinemia group. Nine of these subjects had only this isolated risk factor. No correlations were found between HCy and antithrombin III, protein C, protein S and plasminogen levels, or plasma plasminogen activator inhibitor activity. Nevertheless, the correlation between tissue-plasminogen activator antigen and total plasma HCy was significant (r = 0.61, p < 0.001). Increased homocysteinemia seems to be a risk factor for thrombotic events especially knowing that HCy presents a direct cytotoxic effect. Vitamin therapy, already used in homozygote homocystinuric patients, might be beneficial in the prevention of thromboembolic disease in heterozygous patients.

Beraprost sodium-fluindione combination in healthy subjects: pharmacokinetic and pharmacodynamic aspects.

Beraprost sodium (BPS), an orally active PGI2 (prostaglandine 12) analogue possesses vasodilatating and platelet aggregation inhibiting properties. It is being developed in peripheral arterial occlusive disease. As in future clinical practice BPS might be co-prescribed with oral anticoagulants, we investigated its interaction with fluindione, a vitamin K antagonist in healthy subjects in a randomised, double-blind, placebo-controlled, crossover study. Twelve healthy Caucasian male subjects randomly received BPS 40 microg t.i.d. or placebo for 3 days. There was a 7 day wash out between the two treatment periods. On day 3 of each treatment, the subjects ingested concomitantly a single oral dose of 20 mg of fluindione. The main assessment criterion was fluindione's pharmacokinetics. Secondarily, pharmacodynamic measurements of coagulation (prothrombin time, and International Normalised Ratio, INR) and platelet function (in vitro closure time assessed by PFA-100) were performed. Fluindione was assayed by HPLC with UV detection up to 96 h post-drug. No statistical difference could be evidenced on any fluindione pharmacokinetic parameters between BPS and placebo phases: t 1/2 (h): 35.9 (8.2) vs. 34.0 (4.2) [90% CI 105.8 (95.5-116.2)]; T(max) (h): 2.0 (0.5-6.0) vs. 4.0 (0.5-6.0) [90% CI 136.4 (70.7-208.9)]; Cmax (mg/L): 3.1 (0.6) vs. 2.9 (0.5) [90% CI 94.1 (85.8-103.2)]; AUC 0-inf (mg/h/L): 117.0 (31.5) vs. 113.9 (33.8) [90% CI 97.6 (87.5-108.8)]. The studied doses of BPS did not affect platelet function, at least as assessed by the in vitro platelet function testing. Twenty milligrams of fluindione marginally modified the PT ratio and INR, however, no statistically significant difference was found between BPS and placebo phases. In conclusion, a 3 day regimen of BPS 40 microg t.i.d. by oral route does not seem to affect pharmacokinetic parameters of a fluindione 20 mg single dose.

Enoxaparin in unstable angina patients with renal failure.

The dosage of the subcutaneous low molecular weight heparin enoxaparin in unstable angina patients undergoing coronary angiogram and coronary angioplasty depends clearly on the renal function. It should be significantly reduced to 64% of the standard dose (1 mg/kg per 12 h) in patients with severe renal failure (creatinine clearance<30 ml/min) to provide a safe anticoagulant profile.

Plasma homocysteine and the extent of atherosclerosis in patients with coronary artery disease.

Homocysteine is a graded risk factor for the incidence of stroke and for the degree of carotid atherosclerosis. Homocysteine is also a graded risk factor for the incidence of myocardial infarction but we do not know its precise relations to the severity of atherosclerosis in coronary patients. Seventy five symptomatic coronary patients were recruited for the study. Fifty of these patients had coronary artery disease only and were compared in a case-control manner to 50 healthy controls matched for age and sex. The 25 other coronary patients had also symptoms in another atherosclerotic territory (cerebral, peripheral or both) and were also compared to 25 matched controls. Mean plasma homocysteine level was significantly higher in coronary patients than in controls (11.7 +/- 0.7 mumol l-1, n = 50 versus 9.9 +/- 0.5 mumol l-1, n = 50, p < 0.05). Homocysteine in patients with symptomatic atherosclerosis in two or three arterial sites was 15.7 +/- 1.5 mumol l-1 which differed significantly from matched controls and from patients with coronary artery disease only (p = 0.01). The extent of coronary atherosclerosis evaluated by an angiographic coronary score correlated weakly to plasma homocysteine levels (r = 0.25, p < 0.05). The patients with both hypertension and high levels of homocysteine (> 11.3 mumol l-1, median value) had more severe coronary atherosclerosis (coronary score of 16.3 +/- 2.3 versus 11.9 +/- 0.9, p < 0.05) and more diffuse atherosclerosis (number of atherosclerotic territories of 1.5 +/- 0.2 versus 1.2 +/- 0.7, p = 0.08) than the coronary patients without this association. There were no other high risk association when considering the other classical risk factors. Thus, the highest levels of homocysteine were present in patients with coronary disease and another symptomatic localisation of atherosclerosis. A small gradient in the extent of coronary atherosclerosis was found with increasing levels of homocysteine. The presence of both hypertension and hyperhomocysteinemia was associated with more severe coronary atherosclerosis.

[Effects of ultrasonic energy on blood clots in vitro]. / Effets de l'énergie ultrasonore sur des caillots sanguins in vitro.

Ultrasound may be used to dissolve arterial and venous thrombi. Its effects depends on the mode of ultrasonic vibration and on the length of the guide wire. The authors studied the in vitro effects of an ultrasonic angioplasty device coupled with a 130 cm long titanium flexible guide wire. The system comprises an automatic scanning function to determine the optimal frequency of resonance and works in the continuous mode of emission. Sixteen thrombi were studied of which 8 were acellular and 8 whole blood. In each group, 4 were treated in association with streptokinase and 4 by ultrasound alone. The ages of the thrombi in each subgroup were 1, 3, 7 and 15 days. All the thrombi were dissolved in 6 minutes or less (3'15" +/- 1'35") at an average optimal frequency of resonance of 19,444 Hz. Ninety six per cent of the debris had a diameter less than 10 microns. Less than 1% of the debris had a diameter larger than 100 microns. These large particles were observed in cellular thrombi and were almost completely absent in dissolved acellular thrombi. They were very fragile. The dissolution of the thrombi was not accelerated by the association of streptokinase. The ultrasonic energy did not induce D-dimer production and its action was probably due to cavitation. Ultrasonic energy could provide an alternative treatment for thrombotic vascular occlusion provided that more flexible guide wires could be designed.