The objective of our study was to examine the changes in coagulation parameters and inflammatory reaction over the course of 15 days in patients with severe sepsis. We tried to identify mechanisms by which sepsis-induced pathophysiological changes may influence the effectiveness of subcutaneously (SC) administered enoxaparin 40 mg once daily.

A total of 16 patients (8 men, 8 women; age 35-83 years) meeting the inclusion criteria of severe sepsis were enrolled in this study. The follow-up was performed on days 1, 2, 3, 6, 9, 12, and 15 of hospitalization at the intensive care unit (ICU). Blood coagulation (activated partial thromboplastin time [aPTT], prothrombin time [PT], fibrinogen, antithrombin (AT), protein C [PC], <scp>d</scp>-dimer, fragment 1.2 [F1.2], factor Xa [FXa] inhibition) and inflammatory reactants (interleukin 6 [IL-6], C-reactive protein [CRP], orosomucoid, -1-antitrypsin) were tested.

The mean FXa inhibition was 0.17 (±0.17) IU/mL. The arbitrarily established range of FXa inhibition for prophylaxis, 0.2 to 0.4 IU/mL, was reached in 22 cases (20%), while in 74 cases (68%), it was below and in 13 cases (12%) above the aforementioned range. Factor Xa inhibition positively correlated with AT (r = .42; P < .001) and PC (r = .45; P < .001) activities. A negative correlation was found between the FXa inhibition and -1-antitrypsin concentrations (r = –.33; P = .01) but only in the subgroup with -1-antitrypsin concentrations ≥2.2 g/L.

We confirmed that in most patients with sepsis, the prophylaxis with enoxaparin did not lead to the required FXa inhibition. The inhibition of FXa by enoxaparin depends mainly on the AT and PC activities.

Background: Adequate fibrinogen concentration is a crucial component of sufficient perioperative/posttraumatic hemostasis. In major blood loss, large volumes of fluids are being administered, which have been shown to interfere with valid determination of fibrinogen concentration. This may lead to wrong treatment decisions. We studied the variables that cause the discrepancies between measured and true fibrinogen concentrations in samples diluted with volume replacement fluids.

Methods: Citrated plasma samples of healthy volunteers were diluted by 30% and 50% with phosphate buffered saline (PBS), hydroxyethyl starch (HES) 10% (200/0.5), or gelatine (GEL). Fibrinogen concentrations of diluted samples were derived from the prothrombin time (PT) and the Clauss method (CLS) was applied. With the latter, several modifications and combinations of detection principles and thrombin reagents were investigated. Values were compared with "true," that is, calculated values based on the results of undiluted samples for each method.

Results: Photo-optical methods resulted in significant overestimation of the fibrinogen concentration in blood diluted with HES, depending on the thrombin reagent used. This was particularly true for modifications of the CLS aimed at measuring low fibrinogen concentrations. Use of another thrombin reagent gave satisfactory results for this modification. The validity of mechanical end point determination methods was considered sufficient and was not influenced by the use of different thrombin reagents.

Conclusions: Fibrinogen determination methods used in situations of major blood loss need to be validated with samples containing significant amounts of volume replacement fluids, particularly colloids. Only some combinations of test principle, detection method, and reagents will give valid results.

Objective: The purpose of this study was to investigate the effects of acute hypervolemic fluid infusion (AHFI) of 6% hydroxyethyl starch (HES) 130/0.4 or 4% succinylated gelatin (GEL) on hemostasis and the possible mechanisms.

Methods: Thirty-six gastric cancer patients were randomized to receive AHFI of either HES, GEL or lactated Ringer’s (RL) solution at the rate of 30 mL·kg^-1·h^-1 from 20 minutes before to 40 minutes after induction of general anesthesia.

Results: Group HES and GEL had significantly prolonged PT and aPTT, decreased VIII:C and vWF immediately after AHFI. Statistically prolonged reaction time and coagulation time, and decreased growth angle were seen immediately after HES infusion. Maximum amplitude decreased significantly in group HES and GEL immediately after and 4 hours after AHFI.

Conclusion: Gelatin reduced clot quality associated with derangements of fibrin polymerization and HES 130/0.4 delayed initiation of sufficient thrombin generation to convert fibrinogen to fibrin and impaired platelet function.

Lipoprotein (a) is a cholesterol-rich plasma lipoprotein with a lipid composition similar to that of low-density lipoproteins (LDL). Many prospective and case-control studies identified elevated levels of lipoprotein (a) as a risk factor for premature myocardial infarction and stroke. Elevated lipoprotein (a) has been identified as a genetically determined risk factor for stroke in young adults, but only preliminary data are available on its role as a risk factor for ischemic stroke in infants and children.

Fifty two children with arterial ischemic stroke and 78 age- and sex-matched healthy children were studied. Data of this study indicate that 26.9% of children with arterial ischemic stroke had high lipoprotein (a) levels in comparison with the age matched healthy control group.

Measurement of lipoprotein (a) should be included in screening programs performed in young patients suffering not only from venous thromboembolism but also arterial ischemic stroke, in addition to other thrombophilic factors.

Background: One of the major concerns remaining in the treatment with stenting of patients with acute myocardial infarction (AMI) is the occurrence of stent thrombosis (ST). The aim of the current study is to investigate the incidence, predictors, and long-term outcomes of early ST after primary coronary stenting for AMI in a large population.

Method: We reviewed 1960 consecutive patients (mean age 56 ± 11.6 years, 1658 males) treated with primary coronary stenting for AMI between 2003 and 2008. All clinical, angiographic, and follow-up data were retrospectively collected. Early ST was defined as thrombosis that occurred in the first 30 days after primary coronary stenting.

Result: Early ST was observed in 89 (4.5%) patients. Five variables, selected from the multivariate analysis, were weighted proportionally to their respective odds ratio (OR) for early ST (premature clopidogrel therapy discontinuation [10 points], stent diameter ≤3 mm [5 points], current smoker [4 points], diabetes mellitus [DM; 3 points], and age >65 years [2 points]). Three strata of risks were defined (low risk, score 0-4; intermediate risk, score 5-12; and high risk, score 13-24) and had a strong association with early ST and long-term cardiovascular mortality. Long-term cardiovascular mortality was 5-fold more in patients with early ST than that without ST (24.1% vs 4.7%, respectively, P < .001).

Conclusion: Early ST after primary coronary stenting in AMI is strongly related with increased long-term cardiovascular mortality. Premature clopidogrel therapy discontinuation is the most powerful predictor of early ST.

Although effective, vitamin K antagonists (VKAs) are challenging to use because of their slow onset and offset of action, narrow therapeutic window, multiple dietary and drug interactions, and unpredictable anticoagulant effect. Accordingly, it is recognized that there is an unmet need for an oral thrombotic inhibitor that does not require monitoring and has a rapid onset of action. There is also an unmet need in the field of thromboprophylaxis against venous thromboembolism (VTE) in high-risk patients. The topic of this Supplement is the evidence for the use of dabigatran in high-risk orthopedic patients, namely patients with hip and knee athroplasty. An oral therapy with an immediate reliable and predictable anticoagulant effect without the need for coagulation monitoring and without any long-term hepatic or safety concerns will be a major advance in the management of patients with various thrombotic disorders.

Objective: We aimed to compare the effects of 2 different antiplatelet agents on platelet activity in patients receiving atorvastatin after coronary artery bypass grafting (CABG). Methods: We prospectively randomized 50 patients undergoing CABG into 2 groups; group 1 started to receive atorvastatin (10 mg) plus clopidogrel (75 mg; C + A, n = 25) and group 2 atorvastatin (10 mg) and acetylsalicylic acid (ASA; 300 mg, ASA + A, n = 25) daily on postoperative day 1 and continued for 6 months after operation. Adenosine diphosphate (ADP)–induced platelet aggregation and the expressions of glycoprotein (Gp) IIb, GpIIIa, P-selectin, and fibrinogen (Fg) and low-density lipoprotein (LDL) binding to platelets were assessed preoperatively and at postoperative days 7, 90, and 180. Results: The mean age of the patients was 59.6 ± 7.6 years, and 82% of the patients were males. The combination of C + A markedly inhibited ADP-induced platelet aggregation compared with ASA + A at postoperative days 90 and 180 (52% ± 6.0% vs 56% ± 7.25% and 19.6% ± 3.2% vs 37% ± 4.1%, P =.039 and P = .0001, respectively). The therapy of C + A significantly suppressed the expressions of GpIIIa at postoperative days 7, 90, and 180 (P = .0001, P = .0001, and P = .0001, respectively) and P-selectin at postoperative days 90 and 180 (P = .035 and P = .002, respectively) when compared to ASA + A. The expression of GpIIb was also significantly depressed at postoperative day 180 in group 1 when compared to group 2 (P = .0001). Low-density lipoprotein binding was significantly increased at day 180 postoperatively in both the groups (basal: 42.9% ± 5.6% vs 45.3% ± 4.4% and day 180: 60.3% ± 4.6% vs 61.8% ± 5.7%, P = .0001). Conclusions: Our results demonstrate that the combination of C + A is more effective than that of ASA + A in inhibiting ADP-mediated platelet aggregation and expression of major platelet receptors after CABG.

The present study aimed at investigating the prevalence of factor V Leiden G1691A, prothrombin G20210A, and MTHFR C677T in cerebral venous and sinus thrombosis (CVST) patients and their possible association with CVST in Western Iran. A total of 24 CVST patients with the mean age of 37.1 ± 11.7 years and 100 sex- and age-matched healthy individuals from Kermanshah Province of Iran with ethnic background of Kurd were studied for factor V Leiden G1691A, prothrombin G20210A and MTHFR C677T by PCR-RFLP method using Mnl I, Hind III, and Hinf I restriction enzymes, respectively. Prevalence of factor V Leiden was 16.7% in patients and 2% in control group. A significant association was found between factor V Leiden mutation and CVST with odds ratio (OR) of 9.8 (95% confidence intervals [CI] 1.68-57.2, P = .01). No prothrombin G20210A was found among patients. In patients, MTHFR C677T tended to be higher (58.3%) compared to control (44%), OR of 1.8 (95% CI 0.73-4.5, P = .2). Our study for the first time has determined the prevalence of inherited thrombophilia in a homogenous ethnic group of CVST patients and suggests that factor V Leiden, and not the prothrombin gene mutation is a risk factor for CVST in Western Iran.

The aim of this study was to detect the prevalence of the polymorphisms of growth arrest–specific gene 6 (Gas6; Gas6 c. 834 + 7G > A) in patients with sticky platelet syndrome (SPS). Sticky platelet syndrome is a hereditary, autosomal dominant thrombophilia characterized by platelet hyperaggregation after low concentrations of platelet inducers—adenosine diphosphate (ADP) and epinephrine (EPI). The cause of SPS still remains unknown, but in recent years it was suggested that Gas6 protein may have a potential role in the pathogenesis of SPS. To assess the Gas6 polymorphisms (Gas6 c. 834 + 7G > A), 128 patients with SPS were included in the study and examined by polymerase chain reaction (PCR) method. GG genotype was detected in 63 (49.2%) patients, GA genotype in 53 (41.4%) patients, and AA genotype in 12 (9.4%) patients. The results in controls did not differ significantly compared to patients with SPS. Our findings did not prove allele A to be less associated with thrombosis and that "prothrombotic" allele G may be associated with higher risk of thrombosis. We cannot support the idea that Gas6 protein and Gas6 polymorphisms may be associated with thrombosis in SPS.

Dabigatran etexilate is an oral reversible direct thrombin inhibitor that offers potential practical advantages over existing anticoagulants for the prevention of venous thromboembolism after major joint replacement surgery. These include oral administration, rapid onset of action, and a predictable anticoagulant effect that obviates the need for laboratory monitoring. Evidence from 3 phase II dose-finding trials showed that dabigatran etexilate, 100 to 300 mg daily, had similar efficacy, risk of bleeding, and tolerability compared with enoxaparin. Using pharmacokinetic modeling and taking into account efficacy/safety considerations, dabigatran etexilate 150 mg and 220 mg once daily, with a half-dose on the day of surgery, were selected for further evaluation in phase III trials. These doses were selected to ensure that the risk of bleeding did not exceed that of enoxaparin. This review discusses the rationale for selection of these dose regimens based on results from phase II trials.

Dabigatran etexilate is a novel, oral reversible direct thrombin inhibitor that is rapidly absorbed and converted to its active form, dabigatran. Dabigatran has been shown to be a potent, competitive, and reversible inhibitor of thrombin, inhibiting both thrombin activity and generation. Studies in healthy volunteers and in patients undergoing orthopedic surgery indicate that dabigatran has a predictable pharmacokinetic profile, allowing for a fixed-dose regimen without the need for coagulation monitoring. In healthy volunteers, peak plasma concentrations of dabigatran are reached approximately 2 hours after oral administration. The elimination half-life is 12 to 14 hours, with clearance predominantly occurring via renal excretion of unchanged drug. Dabigatran is not metabolized by cytochrome P450 isoenzymes, has no interactions with food, and also has a low potential for drug–drug interactions. The pharmacokinetic profile of dabigatran is consistent across a broad range of different patient populations and is unaffected by gender, body weight, ethnic origin, obesity, and mild-to-moderate hepatic impairment. Small differences in dabigatran pharmacokinetics associated with age are attributable to variation in renal function. Dabigatran etexilate produces a predictable pharmacodynamic effect and requires no coagulation monitoring. It has been approved in the European Union (EU) and Canada for prophylaxis of thromboembolism in patients undergoing total knee or hip arthroplasty. Ongoing clinical trials are investigating its use in the treatment of venous thromboembolism, prevention of stroke in patients with nonvalvular atrial fibrillation, and treatment of thromboembolic complications, following acute coronary syndromes.

Rotation thrombelastography (ROTEM) provides a whole blood assay that allows the assessment of plasmic- and platelet-related hemostasis in a single-step procedure. In our current study, we focused on the capability of the method to detect hemostatic alterations induced by physical exercise, enrolling 33 healthy participants of the Dusseldorf Marathon 2006. Venous blood drawn immediately before and after finishing the marathon was analyzed by a rotational thrombelastograph (Pentapharm, Munich, Germany). On initiation of blood coagulation by recalcification, standard ROTEM parameters were determined. Comparison of the results obtained before and after the physical exercise was performed using the Student t test for paired samples. As a result, the mean clotting time (CT) determined from blood samples obtained immediately after the marathon was significantly shorter (662.9 ± 67.8 seconds vs 505.6 ± 97.3 seconds, P = .002) and the mean maximal clot firmness was significantly broader (48.4 ± 6.6 mm vs 51.5 ± 4.5 mm, P = .0004) when compared to results obtained before the physical exercise. Differences between mean clot formation times (CFTs; 280.6 + 96 seconds vs 270.4 ± 73.8 seconds) and mean angles (45.9° ± 8° vs 47.8° ± 5.8°) before and after the marathon were not statistically significant. Remarkably, some participants showed opposed results, particularly prolongation of CT and narrowing of maximum clot firmness (MCF). Our study demonstrates that ROTEM is sensitive to exercise-induced hemostatic alterations. The method appears to be capable of detecting even distinct changes in hemostasis in a single-step procedure. Further analyses are needed to clarify which hemostasis parameters influence ROTEM results and which ROTEM results are independent predictors of exercise-induced alterations of plasmic and platelet function. This might help to explain interindividual differences in exercise-induced alterations of hemostasis.

Inflammation and coagulation occur concomitantly in sepsis. Thrombin activates platelet that leads to P-selectin translocation, which upregulate tissue factor (TF) generation. Tissue factor pathway inhibitor (TFPI) is an anticoagulant that modulates coagulation induced by TF. The term non-overt disseminated intravascular coagulation (DIC) refers to a state of affairs prevalent before the occurrence of overt DIC. It was suggested that an initiation of treatment in non-overt DIC has better outcome than overt DIC. This study investigated the role of TFPI level, P-selectin, and thrombin activation markers in non-overt and overt DIC induced by sepsis and its relationship to outcome and organ dysfunction as measured by the Sequential Organ Failure Assessment (SOFA) score. It included 176 patients with sepsis. They were admitted to the pediatric intensive care unit (ICU).They included 144 cases of non-overt DIC and 32 cases of overt DIC. There was a significant difference in hemostatic markers, platelet count, partial thromboplastin time (PTT), P-selectin, thrombin activation markers, TFPI, and DIC score between overt and non-overt DIC in both groups. It was noticed that P-selectin was positively correlated with DIC score, fibrinogen consumption, fibrinolysis (d-dimer), thrombin activation markers, and TFPI. Tissue factor pathway inhibitor was significantly correlated with fibrinolysis, DIC score, and prothrombin fragment 1+2. Sequential Organ Failure Assessment score was correlated with DIC score and other hemostatic markers in patients with overt DIC. To improve the outcome of patients with DIC, there is a need to establish more diagnostic criteria for non-overt-DIC. Plasma levels of TFPI and P-selectin may be helpful in this respect.

Aim: The objective of this study was to elucidate the effects of tumor necrosis factor (TNF-), interleukin 1β (IL-1β), interleukin 2 (IL-2), interleukin 6 (IL-6), and interleukin 8 (IL-8) on the expression of soluble endothelial protein C receptor (sEPCR) in the pathogenesis of thrombotic complications after hematopoietic stem cell transplantation (HSCT). Methods: The relationship between plasma concentrations of proinflammatory cytokines (TNF-, IL-1β, IL-2, IL-6, and IL-8) and sEPCR was evaluated in 32 consecutive allogeneic hematopoietic stem cell–transplanted patients prior to conditioning regimen and randomly once between +5 and +30 days after transplantation and compared these results with 20 healthy controls. Results: Soluble endothelial protein C receptor levels did not indicate any significant difference between pre- and posttransplantation period, and sEPCR levels showed a significantly negative correlation between IL-6 and IL-8 (sEPCR and IL-6, r = -.43, P < .01; sEPCR and IL-8, r = -.57, P < .01). There was no correlation between sEPCR levels and TNF-, IL-1β, or IL-2 (sEPCR and TNF-, r = -.13, P > .05; sEPCR and IL-1β, r = -.1, P ≥ .05; sEPCR and IL-2, r = -.07, P > .05). Conclusions: Our results suggest that the production of sEPCR was not affected by allogeneic HSCT. Soluble endothelial protein C receptor did not show any positive correlation between these proinflammatory cytokines (TNF-, IL-1β, IL-2, IL-6, and IL-8), on the contrary a significantly negative correlation was determined between sEPCR and either IL-6 or IL-8. This negative correlation may be a protective mechanism in the pathway of protein C activation.

Dabigatran etexilate is a novel, oral reversible direct thrombin inhibitor in the clinical development for the treatment and prevention of thromboembolic diseases. Clinical data indicate that dabigatran etexilate has immediate onset of effect, no need for monitoring, predictable and consistent pharmacokinetics and pharmacodynamics—all features that differentiate it from oral vitamin K antagonists (VKAs). Completed phase III studies demonstrated a comparable efficacy and safety profile to enoxaparin in the prevention of venous thromboembolism (VTE) after orthopedic surgery. Ongoing phase III trials are now evaluating the long-term use of dabigatran etexilate for the treatment and secondary prevention of VTE and for prevention of stroke in patients with atrial fibrillation, as a replacement for VKAs. With an immediate, reliable, and predictable anticoagulant effect without the need for coagulation monitoring and the lack of long-term safety concerns, dabigatran etexilate may be a prospective candidate that offers additional benefit over VKAs and parenteral anticoagulants in these settings.

A 23-year-old woman developed ischemic stroke (IS) 8 to 12 hours after ingestion of sumatriptan (ST) and then developed mucosal bleeding secondary to acute thrombocytopenia likely due to dipyridamole (DP) on the 10th day poststroke. Sumatriptan-associated IS and DP-induced thrombocytopenia are rare events in themselves and their sequential occurrence in the same patient is quite exceptional. We compare our case to other similar cases in the literature.

Although the use of recombinant activated factor VII (rFVIIa) to control intractable bleeding in nonhemophiliac patients is expanding, several issues pertinent to its potential thrombotic complications and effect on patient mortality are still of concern. We herein describe our experience at a developing country tertiary care center over a period of 4 years. A total of 49 patients were identified of whom 28.6% belong to the pediatric age group. The most common bleeding settings were intracerebral hemorrhage, abdominal aortic surgery, general surgery, and disseminated intravascular coagulopathy. All patients achieved cessation or significant reduction in bleeding. Only 1 patient had a documented postuse thrombotic complication. Of the whole group, 12 patients (24.4%) eventually died with only 1 death having a possible association to rFVIIa use. There was a statistically significant reduction in the need for blood product transfusion after the use of rFVIIa. The use of rFVIIa was in accordance with the hospital’s algorithm (identifying salvageable patients, preconditioning, blood product replacement, and dosing) in 30 (61.2%) patients. We conclude that rFVIIa should continue to be considered in nonhemophiliac patients failing to respond to conventional measures of bleeding control. However, this off-label use should be coupled with strict adherence to the treatment algorithms, which remains essential in developing countries with limited health care resources.

A 21-year-old girl with an ischemic bowel developed portal and splenic vein thrombosis 3 weeks later, despite thromboprophylaxis low-molecular-weight heparin. An extensive thrombophilia screen was negative and the only possible reason for her vascular occlusion was transient but severe eosinophilia. The role of transient eosinophilia in thrombosis is discussed in the light of other similar rare cases.

Objective: Recently, mechanical thrombolytic therapy has been introduced as an alternative or adjunct to pharmaceutical thrombolytic therapy in removing thrombus from vascular system. Recurrent thrombosis has been a challenge for thrombolytic therapies. We hypothesize that soluble clotting factors released during a mechanical thrombectomy procedure may be responsible for creating a localized hypercoagulable state and could be one of the underlying causes of recurrent thrombosis. Method: Blood samples were obtained from 20 participants with no history of hypertension, vascular disease, and antiplatelet/anticoagulation therapy. For each whole blood (WB) sample, we measured activated clotting time (ACT) and clotting rate (CR) at the baseline and then with added agitated and nonagitated clot serums. The same set of measurements was performed on platelet-rich plasma (PRP) samples of each participant. We tested for changes in coagulation profile between baseline samples and those with added supernatant serums obtained from autologous blood clot. Result: We observed a significant decrease in ACT for WB with agitated and nonagitated clot serums (49%, P < .0001and 25%, P = .01, respectively) compared to the baseline WB. The same trend was observed for PRP samples with agitated and nonagitated clot serums (28%, P = .002 and 18%, P = .05, respectively). The CR was increased (a steeper slope) by 83% for samples with added agitated clot serum only (P = .007). Conclusion: We observed a significant change for ACT in WB samples with added clot serums as compared to the baseline WB samples. The results of this study suggest that the soluble substances released from clotting blood have profound procoagulant effects.

Background Platelet-derived microparticles (PDMPs) have attracted attention as blood coagulation-promoting, endothelial cell-activating factors. The objective of this study was to determine the parameters associated with elevated PDMP levels and examine their relationship with atherosclerotic lesions of main intracranial and extracranial arteries. Participants and Methods Participants included a control group (C) of 61 patients with no apparent cerebral vascular lesions and 110 patients with acute-phase cerebral infarction, consisting of a small-vessel occlusion group (S) of 34 patients, a large-artery atherosclerosis group (L) of 41 patients, a cardioembolism group (CE) of 20 patients, and a stroke of undetermined etiology group (U) of 15 patients. Platelet-derived microparticle levels were measured using enzyme-linked immunosorbent assay (ELISA) at the time of admission, and the patients were reclassified into group CP (control level PDMPs), consisting of 70 patients with control PDMP levels, and group HP (high PDMPs), consisting of 40 patients with elevated PDMP levels. All patients underwent cranial magnetic resonance (MR) and carotid ultrasound examinations. Results Platelet-derived microparticle levels were significantly higher in groups S and L than in group C (P < .01). Concomitant intima-media thickness (IMT; odds ratio [OR] = 1.29, P < .05) and concomitant intracranial stenosis (OR = 3.95, P < .01) were significantly correlated with elevated PDMP levels. Fibrinogen and high-sensitivity CRP levels were significantly higher in group HP than in group CP. Conclusion Alterations in PDMP levels correlated with the presence of atherothrombotic lesions, and PDMP levels are expected to be useful as a clinical indicator, reflecting the presence of intracranial atherosclerotic lesions in the acute phase of cerebral infarction.

Introduction India is one of the few countries where biosimilar enoxaparin is available for clinical use. Despite availability since past 4 to 5 years, there is a paucity of published literature regarding their biological activity. The aim of the current study is to compare the biological activity of an endogenously developed formulation of enoxaparin with the branded formulation. Materials and Methods Twelve healthy male volunteers received 1 subcutaneous injection of 2 different formulations of enoxaparin in a randomized, open-label, balanced, 2-treatment, 2-period, 2-sequence, cross-over study. The test formulation was Injection Troynoxa (enoxaparin sodium 40 mg/0.4 mL, Troikaa Pharmaceuticals Ltd., India) and reference formulation was Injection Clexane (enoxaparin sodium 40 mg/0.4 mL, Sanofi-Aventis, UK). The plasma anti-Xa activity and activated partial thromboplastin time (aPTT) were estimated on fully automated coagulometer predose and at 2, 4, 6, 8, and 10 hours following dosing with 40 mg/0.4 mL of enoxaparin. Results The results of mixed model analysis of repeated measures analysis of variance (ANOVA) for estimating difference between least square means of test and reference formulations, at all time points, showed no significant differences in anti-Xa activity and plasma aPTT levels. Both formulations were well tolerated and there were no bleeding episodes. Conclusion After a single-dose injection in healthy participants, anti-Xa activities of 2 formulations of LMWH enoxaparin were comparable. No significant difference was observed in the mean plasma aPTT. It remains to be seen whether the 2 formulations would show comparable clinical efficacy.

Background: Most patients with malignant diseases are frequently complicated with some type of thrombosis, such as disseminated intravascular coagulation (DIC) or deep vein thrombosis (DVT)/pulmonary embolism (PE). Objective: The cohort and retrospective study was designed to examine the frequency of thrombosis in patients with malignant diseases and to evaluate the efficacy of D-dimer and soluble fibrin (SF) for the diagnosis of thrombosis. Patients/Methods: The plasma concentrations of D-dimer and SF were measured in patients with malignant diseases suspected of having thrombosis. D-dimer and SF were measured using a latex aggregation assay. Results: Thrombosis was observed in 23.3% of the patients with malignant diseases. Disseminated intravascular coagulation was frequently observed in patients with hepatoma, and DVT/PE was frequently observed in patients with colon cancer, lung cancer, and uterine cancer. The plasma levels of D-dimer and SF were increased in malignant diseases, especially hepatoma. Plasma levels of D-dimer and SF were significantly higher in patients with thrombosis in comparison to patients without thrombosis. A receiver operating characteristic (ROC) analysis showed the D-dimer and SF levels to be useful in the diagnosis of thrombosis. Conclusion: Elevated D-dimer and SF levels might indicate a high risk of thrombosis in patients with malignant disease; however, these assays still need to be standardized.

Dabigatran etexilate, an oral direct thrombin inhibitor, was investigated in 3 large phase III trials for the prevention of venous thromboembolism (VTE) after total hip arthroplasty (RE-NOVATE, N = 3494) or total knee arthroplasty (RE-MODEL, N = 2076 and RE-MOBILIZE, N = 2615). RE-NOVATE and RE-MODEL were conducted mainly in Europe, and RE-MOBILIZE was conducted predominantly in the United States and Canada. This review discusses the results of these trials. In all 3 trials, 2 doses, 220 mg and 150 mg once daily, were compared with enoxaparin. Both RE-MODEL and RE-NOVATE demonstrated noninferiority for the primary outcome (a composite of total VTE events and all-cause mortality), P = .0003 and P < .0001, respectively, for these trials. In 2008, these data formed the basis for European and Canadian approval. While RE-MOBILIZE did not demonstrate noninferiority for the primary outcome (25.3% for enoxaparin vs 31.1% for 220 mg, risk difference +5.8%, 95% CI, 0.8-10.8; P = .02 and 33.7% for 150 mg, risk difference +8.4%, 95% CI, 3.4-13.3; P = .0009), both treatments were similar for the secondary composite outcome (major VTE plus VTE-related mortality; 3.4% with 220 mg, 3.0% with 150 mg, and 2.2% with enoxaparin) and symptomatic deep vein thrombosis (0.8%, 0.7%, and 0.6%). There were no differences in the bleeding rates, hepatic enzyme elevations, or acute coronary syndrome events between the 2 treatments. With the practical advantages of once-daily oral dosing, dabigatran etexilate can be considered an attractive alternative to conventional thromboprophylaxis regimens in patients undergoing elective total hip and knee arthroplasty.

Atraumatic osteonecrosis has been associated with a variety of clinical conditions including corticosteroid usage, alcoholism, infections, hyperbaric events, storage disorders, marrow-infiltrating diseases, coagulation defects, and some autoimmune diseases. Osteonecrosis due to thrombophilia is an extremely rare condition with only few cases reported previously in the literature. Hormone-replacement therapies cause increased risk of venous thrombosis, probably by causing a synergistic effect with inherited clotting defects. In this article, we report a young female with Turner syndrome, who developed avascular necrosis of the femoral head during treatment with oral estrogen, which was associated with low protein S levels.

This study was performed to investigate the platelet aggregation alterations in platelet-rich plasma (PRP) samples of children with Helicobacter pylori (H pylori) infection. Platelet aggregation induced by adenosine diphosphate (ADP), collagen, ristocetin, or epinephrine was studied with photometric aggregometry in 30 patients before and after eradication therapy and in a control group including 15 children. The pretreatment mean maximum aggregation values and slope were significantly lower (P < .0001) in the study group at 10 µmol/L concentrations of ADP (ADP-like defect). The maximum aggregation values and slope revealed no significant differences (P > .05) between the study group after therapy and the control group. We concluded that H pylori infection may cause dysfunction of platelets in children and can be reversed by H pylori eradication therapy. Further studies should be carried out to determine the mechanisms of platelet dysfunction in children with H pylori infection.

Purpose: The reference values of blood rheology in healthy participants, especially children, are not available. The purpose of this study was to determine the blood passage time (BPT) as an index of blood rheology, in healthy children and adults, using the microchannel array flow analyzer, and to investigate the hematological factors that define BPT. Methods: Participants were 61 healthy children (35 boys, 26 girls; age 5-6 years) and 71 healthy adults (24 men, age 35.2 ± 14.1 years; 47 women, age 44.7 ± 14.1 years, mean ± standard deviation [SD]). Blood passage time and various hematological variables (blood cell count, serum lipids, and fibrinogen) were measured and compared among the 4 study groups. Results: Blood passage time values were significantly higher in adult men (48.8 ± 5.8 seconds) than in boys (41.9 ± 4.0 seconds), girls (43.7 ± 7.8 seconds), and adult women (42.4 ± 4.8 seconds). Stepwise regression analysis identified erythrocyte count and hemoglobin (Hb) as the significant and independent determinants of BPT (P < .05). Conclusion: Our study demonstrates that BPT is significantly longer in healthy adult men than in adult women and children, and that erythrocyte count and Hb are significant determinants of blood rheology.

Factor V Leiden (FVL) is the most common monogenic disorder that causes activated protein C (APC) resistance, creating hypercoagulation. The mutation shows an uneven geographic distribution, significantly high in European populations. The mutation is believed to have originated approximately 20 000 years ago probably from a geographic region close to Anatolia. This fact makes it noteworthy to search for the mutation in ancient populations that once lived in this area. One of these civilizations, Urartu was centered around Van Lake in Eastern Turkey. The archeological remains from the excavations of the region are dated back to 1000 <scp>BC</scp>. Teeth, taken from the excavations of Van Yoncatepe fortress, were taken into DNA analysis considering all the precautions for ancient DNA analysis. Multiplex STR (Short Tandem Repeats) analysis were performed both to determine the gender of the samples and to conclude that the samples are preserved from modern DNA contamination. After getting an 80% amplification success for amelogenin, a melting curve analysis using lightcycler was performed to determine the FVL genotype of each sample. Of the 60 samples, 1 gave a positive amplification result for FV gene and was found to be heterozygous. To date, the age of this mutation was estimated based on statistical calculations using haplotype frequencies; here for the first time, we report FVL in an ancient population of 3000 years.

Background Fibrinogen is the first coagulation factor becoming critical in dilution coagulopathy. Volume replacement in major blood loss is performed with large volumes of crystalloid and colloid solutions. The latter has been shown to compromise accurate photo-optical measurement of fibrinogen. This study determined the influence of different hydroxyethyl starch (HES) formulations.

Methods Citrated plasma samples of 8 healthy volunteers were diluted by 30% or 50% with either HES 10% (200/0.5; HES-200), HES 6% (70/0.5; HES-70), or HES 6% (450/0.7; HES-450). Fibrinogen concentrations were determined by photo-optical measurement (Behring coagulation system [BCS]: derived fibrinogen, or Clauss fibrinogen, calibrated for high [CLS] or low fibrinogen concentrations [CLS-low]) as well as mechanical end point determinations (KC4: CLS-KC4). Measured values were compared with calculated values.

Results On average and across all photo-optical methods, fibrinogen concentrations were overestimated, particularly with HES-200. Hydroxyethyl starch-70 and HES-450 did not differ much from each other. Overestimation was relatively greater for 50% dilutions with all HES formulations. Surprisingly, overestimation was most prominent with CLS-low, the method supposed to most reliably measure low fibrinogen concentrations; overestimation amounted to 92% and 120% with HES-200, 54% and 73% with HES-70, and 51% and 79% with HES-450, for 30% and 50% dilutions, respectively. In contrast, CLS-KC4 always yielded sufficiently accurate results.

Conclusions The study showed that all HES solutions more or less impaired the fibrinogen measurement with the photo-optical method. In particular, overestimation with CLS-low may prevent timely fibrinogen replacement in major blood loss. Hydroxyethyl starch concentration appears to be more relevant for this effect than its molecular size.

Background: Ankaferd blood stopper (ABS) is a standardized herbal extract obtained from 5 different plants. In Turkey, it has been approved for local topical applications in external postsurgical and postdental surgery bleedings. Ankaferd blood stopper, besides its hemostatic activity, has in vitro anti-infectious and antineoplastic actions. Objective: The aim of this study was to assess short-term hematological and biochemical safety following the oral systemic administration of ABS to rabbits. Methods: Twelve rabbits (aged 6-12 months) were included to test the safety of oral ABS. Animals were divided into 4 groups, which had ABS administered orally at doses of 1, 3, 6, and 9 mL, irrespective of their weight. The general well-being and feeding patterns of the animals were observed for a period of 7 days. Blood samples (5.5 mL) were obtained just before oral administration, on days 1 and 4. Results: During the observation period of 7 days, none of the animals showed any abnormal behavior or deviation from the normal. Acute mucosal toxicity, hematotoxicity, hepatotoxicity, nephrotoxicity, and biochemical toxicity were not observed during the short-term follow-up of the animals. Conclusions: No signs of toxicity were observed in rabbits during short-term study with oral ABS administration.

Thrombophilia has recently been reported to be increased in patients with cystic fibrosis (CF). We wanted to determine whether this was applicable to our population with CF and how our patients compared to the previously reported groups. Seventy one pediatric CF patients were assessed for a thrombophilic tendency, using a lupus anticoagulant screen, protein C, protein S, antithrombin assay, and activated protein C resistance (APCR) screen. The incidence of activate protein C resistance (4.2%) was within expected limits for the general population as was the incidence of antithrombin deficiency. However there was a marked increase in the incidence of lupus anticoagulants (18%) and 14% and 19.7% of the patients showed a reduced protein C and protein S, respectively, far in excess of the general population. This increased incidence of thrombophilia was not related to any specific CF phenotype and while perturbed liver function cannot be entirely ruled out, it appeared unlikely to be responsible for all the abnormal coagulation findings. Despite the apparent thrombophilic tendency, no clinically evident thrombotic episodes were noted during the study period. Thrombophilia is of concern because of the increasingly frequent placement of indwelling catheters in CF patients. The precise cause for the thrombophilic tendency in CF patients is unknown at this stage.

Warfarin is the most prescribed oral anticoagulant worldwide. Because of the complexity of warfarin therapy, we attempted to dissect genetic from bioenvironmental factors influencing warfarin dose responses in individuals of a genetic isolate of Hispanic ancestry. A total of 191 patients with standard values of international normalized ratio were recruited. Three groups with a significantly different warfarin dose response were identified, that is, sensitive (2.28 ± 0.50 mg/d), intermediate (4.2 ± 0.76 mg/d), and resistant (7.40 ± 1.54 mg/d; Tukey test, P < .001). Age had a significant inverse correlation with warfarin dose (P < .001; effective dose diminished 0.56 mg/d/decade). Required doses were higher for individuals with CYP2C9 variants containing the allele *1 compared to those individuals with variants composed of other alleles (P = .006). Similarly, individuals with VKORC1-1639GG and VKORC1-1639GA genotypes also required higher doses compared to the AA genotype (P < .001). Evaluation of potential gene-gene interactions between CYP2C9 and VKORC1 polymorphisms showed significant differences in dosing for CYP2C9 genotypes within the VKORC1-1639G/A subgroup (P = .013). A stepwise multivariate linear regression analysis showed that 38.2% of the warfarin dose response variance was accounted for by a model involving age (20.9%), VKORC1-1639G/A (11.3%), and CYP2C9*1, *2, and *3 variants (7.1%). These results corroborate previous findings on warfarin pharmacogenetics and define a contrastable gene-bioenvironment interaction model suited to be used in Hispanic populations.

The treatment of hemophilia A patients with inhibitor could be very expensive. Ankaferd blood stopper (ABS) is a unique folkloric medicinal plant extract, which has historically been used in Turkish traditional medicine as a hemostatic agent. In this article, a 16-year-old boy was presented with uncontrolled bleeding, despite the treatment of factor VIII, rVIIa, factor VIII inhibitor bypass activity (FEIBA), cyclophosphamide, and prednisolone at circumcision site that resolved with ABS in minutes. Our patient with hemophilia A and inhibitor is the first clinical pediatric case.

Warfarin is one of the commonly used oral anticoagulant. The aim of our study is to evaluate the predisposing preventable factors among patients with bleeding due to warfarin usage. This study was performed on 114 cases who were admitted to emergency service for bleeding and whose ages range between 27 and 89 years. The mean time between the onset of the bleeding and admission to the hospital was 2.9 ± 3.4 days. The mean dose of warfarin being used at the time of admission was 31.2 ± 10.8 mg weekly. Only 37 cases were being controlled regularly. The mean number of the drugs being used other than warfarin was 4.8 ± 2.5 drugs. Forty-eight cases were using aspirin, 28 nonsteroidal anti-inflammatory drugs other than aspirin and 18 cases were using various antibiotics. Forty eight patients knew that they had to use this drug under the regular follow-up of a physician and 43 knew that during monitoring a laboratory test had to be done while using the drug named as warfarin. Only 39 patients knew that this drug may cause bleeding. It was also surprising that only 9 patients knew that there may be drug interaction and 1 knew that this drug may be affected from the dietary factors. As a result, it may be concluded that most of the patients admitting to the emergency service had a lack of basic knowledge about this drug, which might invite bleeding.

Dual antiplatelet therapy with aspirin and a thienopyridine (ticlopidine or clopidogrel) has strikingly improved the results of percutaneous coronary intervention (PCI) through a marked reduction in the rate of stent thrombosis (ST). Emerging data suggest that resistance to antiplatelet treatment may be a risk factor for ST. We report about a patient, aspirin and clopidogrel poor responder, who experienced 4 ST in 10 days. After the second ST, during antiplatelet therapy with aspirin (100 mg/die) and clopidogrel (75 mg/die), the patient’s platelet function was investigated with Platelet Function Analyzer 100, VerifyNow P2Y12 System and light transmission aggregometry (LTA). High platelet reactivity and combined resistance to aspirin and clopidogrel were found, and, as a consequence, treatment was switched to clopidogrel 150 mg and aspirin 300 mg/die. In spite of this adjustment, the third ST occurred. Poor responsiveness to aspirin and clopidogrel was still confirmed. Because of combined clopidogrel and aspirin resistance and to unsuccessful PCI treatment, a single coronary artery bypass graft (CABG) was planned. Awaiting surgery, 3 days later, the fourth ST occurred. It is angiographically confirmed and thus, CABG was performed. After CABG, in chronic treatment with aspirin (300 mg/die) and ticlopidine (500 mg/die), no bleeding complications occurred and the patient did not experience recurrent ischemia (2 years follow-up). A better platelet inhibition by ticlopidine than that obtained by clopidogrel was observed. Our case report remarks the importance to identify these poor responder patients as the treatment can be tailored with alternative therapeutic options (ticlopidine, prasugrel, warfarin) and/or different revascularization strategies (CABG).

Low-molecular-weight heparin (LMWH) is now the standard of care for prophylaxis and treatment of thromboembolic disorders. Only cases with renal failure, morbid obesity or extreme age require anti-Xa monitoring to assure the therapeutic level achievement. Because of infrequent requests, the test is usually sent to the reference laboratories and specimen handling may be delayed. Because LMWHs can be kept at ambient temperature for several days, we proposed that anti-Xa levels in plasma samples are similarly steady. Patients' plasma that was requested for anti-Xa activity was left at room temperature to repeat the test 24 hours later and compare with the result of immediate assay. The study included 86 fresh specimens from 56 participants. All patients received enoxaparin with anti-Xa levels ranging from 0.1 to 2.5 U/mL. Notably, anti-Xa activities significantly rose on the second occasions (P = 8.4 x 10^–10). The mean change of anti-Xa was +0.15 ± 0.21 U/mL (+24.9% ± 37.4%). Children (age <15 years) showed more marked alterations than adults (+40.9% vs. +18.2%, P = .008). There was no statistical difference in the degrees of changes between sexes and diagnoses. The data suggest that specimens sent for anti-Xa require prompt handling to prevent falsely elevated values. This observation is new and future research is needed to find the mechanism of this alteration.

Thromboangiitis obliterans (TAO), or Buerger disease, is a segmental occlusive inflammatory disorder of the arteries and veins, and etiopathogenesis is still obscure. It is strongly connected to the use of tobacco products, especially smoking. Smoking cessation is obligatory for success of the medical treatment. In the current study, we investigated the prevalence of endothelial nitric oxide synthase (eNOS) 894 G->T and endothelin-1 (ET-1) 8000 T->C polymorphisms in association with TAO to reveal any possible involvement in the TAO pathophysiology. The T allele of the eNOS 894 G->T polymorphism was found to be associated with the prevention of TAO.

Introduction: Genetic polymorphisms that are found among factors of the coagulation cascade are factor V leiden mutation (FVL), prothrombin (PT), and methylenetetrahydrofolate reductase (MTHFR), reported for thrombotic complications. We have investigated the associations of these gene polymorphisms in patients with end-stage renal disease (ESRD). Methods: We genotyped 258 patients for FV G1691A, PT G20210A, and MTHFR (C677T, A1298C) gene by using polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) analysis and were compared with 569 healthy controls. Serum folate, total homocysteine (tHcys), and vitamin B₁₂ were measured in both patients with ESRD and controls. Results: No homozygous individuals for the mutant AA genotype of FVL G1691A were observed in this study. The frequency of the heterozygous genotypes was (11.2%), which was nearly 3 times higher than that observed in controls (3.2%), with a odds ratio of 3.87 (P = .0001, 95% CI = 2.11-7.11). PT G20210A mutation was missing in both patients and the controls. At MTHFR locus, TT genotype of C677T was present in 9.6% among ESRD, while CC genotype of A1298C was present in 11.7% of the ESRD. In control group, it was significantly low that is, 4.2% and 3.2%, respectively (P = .0034; OR = 2.44, 95% CI = 1.36-4.36 and P < .0001; OR = 4.03; 95% CI = 2.2-7.37). The combined analysis of the 2 genotypes showed further increased risk in ESRD ~15 folds. Further, the carrier of TT and CC genotypes of C677T and A1298C had significantly higher total homocysteine (tHcys) level than those with CC and AA genotypes (P < .001). Conclusion: The carrier of FVL, TT genotype of C677T, and CC genotype of A1298C polymorphisms may act as risk factors for ESRD.

The value of computed tomographic (CT) venography in combination with CT pulmonary angiography has been questioned because of the potential dangers of radiation. Accordingly, we retrospectively evaluated the diagnostic yield of 64-detector CT angiography with CT venography. Among patients who routinely underwent CT venography with CT angiography, the CT angiogram showed acute pulmonary embolism (PE) in 206 of 1903 patients (10.8%). A positive CT venogram in a patient with a negative CT angiogram was shown in 25 of 1903 patients (1.3%). Either the CT angiogram or the CT venogram showed venous thromboembolism in 231 of 1903 patients (12.1%). The proportion of patients with venous thromboembolism diagnosed only by a CT venogram was 25 of 231 (10.8%). In conclusion, the proportion of patients with venous thromboembolism diagnosed only by a CT venogram is sufficiently high to merit consideration of its use especially in those at high risk for DVT.

Recurrent fetal loss (RFL) is a significant clinical problem, occurring in 1% to 5% of reproductive females. Inherited or acquired thrombophilia has been diagnosed in 50% to 65% of women with history of unexplained fetal loss. The objective of our study was to determine the prevalence of thrombophilia in women with unexplained RFL in Serbian population and to find out whether the presence of thrombophilia is associated with pregnancy losses that occur later than 12th gestational week. We have examined 147 women with unexplained RFL or intrauterine fetal death and 128 healthy women with at least 1 uncomplicated pregnancy. The antithrombin (AT), protein C (PC), protein S (PS), activated protein C (APC) resistance, factor V (FV) G1691A, factor II (FII) G20210A, and MTHFR C677T were determined. At least 1 inherited thrombophilic defect was found in 54 (36.7%) of 147 women with repeated fetal losses and in 11 (8.59%) of 128 controls (P < .001, OR 6.17, 95% CI 3.06-12.48). The most common thrombophilic abnormalities were homozygosity for MTHFR 677TT, FV Leiden, and FII G20210A. Deficiency of natural anticoagulants occurred in 10 patients, with protein S deficiency being the most frequent one. Thrombophilia was found in 46 of 94 women with RFL that occurred later than the 12th gestational week and in only 8 of 53 with RPL earlier than 12th week (P = .001). Our study has shown the association between the hereditary thrombophilia and RFL that occurred after the 12th gestational week in Serbian population.

Recently, we have experienced cerebrovascular embolic events in 2 consecutive patients in our outpatient clinic. Accordingly, we want to share our comments with literature on these 2 patients. Both patients had newly diagnosed left ventricular (LV) dysfunction, sinus rhythm, and cerebrovascular event within the first week after initiation of heart failure treatment. Although, our cases are not enough to make a general statement or conclusion, we can recommend that patients with newly diagnosed severe LV dysfunction with normal sinus rhythm and without echocardiographically visible thrombus should also be closely followed up for thromboembolic complications at least during the first weeks of congestive heart failure treatment.

Factor V Leiden (Factor V G1691A), prothrombin gene mutation G20210A, and homozygous C677T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene are known to predispose venous thromboembolism (VTE). We present herein a rare case of a young woman heterozygous for these mutations and taking oral contraceptive pills for less than 2 months, diagnosed to have massive deep venous thrombosis and bilateral pulmonary embolism. The patient was managed for 10 days in the hospital and discharged home on oral anticoagulants. This case suggests that screening for these factors in people with family history of thrombosis and in relatives of patients with these mutations is highly recommended to prevent fatal consequences. In addition, a new guideline for treatment and prophylaxis with anticoagulant for these patients and others who are at risk of developing VTE (American College of Chest Physicians [ACCP] guidelines-Chest 2008) has been published recently. Our recommendation is to promote for the internationally published algorithms through their application, where necessary, to prevent any future thrombotic morbidity or mortality incidents.

Introduction: A number of prothrombotic and fibrinolytic disorders may lead to venous thrombosis. A 4G/5G polymorphism located in the promoter region of plasminogen activator inhibitor-1 (PAI-1) gene has been found to be commonly associated with the levels of PAI-1 and might be a risk factor for deep vein thrombosis (DVT). The aim of this study was to look for the potential association of this polymorphism with DVT in the Asian Indian population. Material and methods: A total of 110 consecutive patients (M:F = 62:48) with idiopathic DVT and equal number of age- and sex-matched healthy controls were the study participants. All study participants were typed for the PAI-1 4G/5G polymorphism, factor V Leiden, factor V Hong Kong/Cambridge mutations, and HR2 haplotype. Result: The variant allele for the PAI-1 4G/5G polymorphism showed both genotypic (P = .0013, ² = 10.303; odds ratio [OR] = 3.75) as well as allelic association (P = .0004, ² = 12.273; OR = 1.99) with DVT. Factor V Leiden and factor V HR2 haplotype were observed in 10 (9.0%) and 13 (11.8%) patients, respectively. None of the study participants showed the factor V Hong Kong Cambridge mutations. Conclusion: Our study shows the association of 4G allele with DVT in Asian Indian population. The higher prevalence of 4G polymorphism in patients with DVT (compared with controls) seen in our study is in concordance with previous reports from the Caucasian population.

Reported here is a 22-year-old professional wrestler who was diagnosed to have Paget-Schroetter syndrome after Greco-Roman wrestling. On substantial neuromuscular examination and laboratory testing, he was found to have also thoracic outlet syndrome and heterozygous mutations for factor V Leiden and methyltetrahydrofolate reductase genes. To the best knowledge of the authors, the concomitance of these pathologies is discussed for the first time in the literature.

Myeloproliferative disorders and the inherited thrombophilias have been described as the main causes underlying the Budd-Chiari syndrome. Moreover, the presence of the JAK2V617F was associated with a higher frequency of Budd-Chiari syndrome in patients who have overt or even latent myeloproliferative disorder. We herein describe a 28-year-old woman who was diagnosed with Budd-Chiari syndrome and later developed an overt myeloproliferative disorder. The patient was found to carry both the JAK2V617F and the prothrombin G20210A mutation in the heterozygous form. The significance of the chronology of diagnosis is highlighted.

Acute cerebrovascular events are not randomly distributed over time but show specific temporal patterns of occurrence. However, most studies focused stroke and little is known about transient ischemic attack. This study aimed to explore the existence of a temporal pattern of transient ischemic attack and the possible influence by the most common risk factors. The analysis included all hospital admissions with the ICD9-CM code for TIA, recorded in the database of the Emilia Romagna region of Italy (1998-2006; n = 43642, mean age 76.8 ± 11.5 years, 45.5% males). Transient ischemic attack was most frequent in autumn and winter and less common in spring and summer (P < 0.0001), with the highest number of cases in October and the lowest in February, and also most frequent on Monday (P < 0.0001). This study shows a seasonal and weekly pattern in occurrence of transient ischemic attack, independent of sex and the presence of the most common risk factors.

Our aim was to investigate the CD40-CD40 ligand system in preeclamptic women. We also studied CD62P and platelet–monocyte aggregates, which have been closely linked to the CD40–CD40L system. Platelet expression of CD40L and CD62P and expression of CD40 on monocytes and platelet–monocyte aggregates were determined by flow cytometry in whole blood from 23 preeclamptic women, 23 normotensive pregnant women, and 23 nonpregnant women. The preeclamptic women showed a significant increase in CD40L and CD62P on platelets and in CD40 on monocytes when compared with normotensive pregnant women and nonpregnant women (all P < .001). There was a significant increase in platelet–monocyte aggregates in preeclamptic women (P < .001) and normotensive pregnant women (P = .003) compared with nonpregnant women. Preeclampsia is associated with activation of the CD40–CD40L system. The activation of this system may contribute to the development or maintenance of the proinflammatory and prothrombotic milieu found in preeclampsia.

The objective of our study was to evaluate the significance of extended antiphospholipid profile in patients with venous thromboembolism without any systemic autoimmune disease. In 140 patients (age 18-69 years; 47.1% men) with venous thromboembolism and 136 control participants we tested anticardiolipin antibodies, anti-beta 2 glycoprotein I (anti-β2-GPI) and also non-criteria antiphospholipid antibodies: antiphosphatidic acid, antiphosphatidylethanolamine, antiphosphatidylglycerol, antiphosphatidylinositol, antiphosphatidylserine. Commercial and in-house enzyme-linked immunosorbent assays were used. The antibodies with significantly higher prevalence in patients (compared to controls) were: immunoglobulin (Ig) M-anticardiolipin antibodies (12.9%; P = 0.035), IgG-anti-β2-GPI (16.4%; P = 0.0032), IgM-antiphosphatidylethanolamine (14.3%; P = 0.014). In most cases, these three antibodies did not overlap. In conclusion, of non-criteria antiphospholipid antibodies, only antiphosphatidylethanolamine were significantly more prevalent in patients with venous thromboembolism, with only minor overlapping with the criteria antiphospholipid antibodies. Our results suggest the possible utility of searching for antiphosphatidylethanolamine in the clinical suspicion of antiphospholipid syndrome and the absence of criteria antiphospholipid antibodies.

Acquired hemophilia A is rare, but life-threatening disorder caused by autoantibody against factor VIII. As it is useful to gather more data on epidemiology, clinical pictures and therapy of it, we evaluated relevant medical findings in 34 acquired hemophiliacs from Dec 1999 to Dec 2007. Eight patients (23.5%) had low titers (<10 Bethesda Unit BU) and 26 patients (76.5%) had high titers of inhibitors (>10 BU). The mean of inhibitors was 548.38 ± 359.27 SD BU. The most common hemorrhagic symptoms were hematoma 21 (33.33%), ecchymosis 16 (25.39%), hemarthrosis 8 (12.69%), hematuria 6 (9.52%), menorrhagia 4 (6.34%), compartment syndrome 3 episodes (4.76%). The eliminator therapies were recruited according to titers of inhibitor and types of bleeding and it's results were 27 efficient treatments (79.4%), 5 partial efficient treatment (14.7%) and two treatments inefficient (5.9%). Elimination therapy using steroid alone or with combination can terminate complete remission in most cases.

We have experienced 2 cases of heparin-induced thrombocytopenia during unfractionated heparin treatment for disseminated intravascular coagulation after surgery for an abdominal aortic aneurysm. In the first case, as a symptom of disseminated intravascular coagulation gradually improved with antithrombin concentrates and heparin treatment, mesenteric artery thrombosis suddenly occurred, associated with a >50% decrease in platelet count on the 11th day. Although the platelet counts were increasing due to heparin cessation, clinical symptom and coagulation abnormalities worsened to multiple organ failure. In the second case, the platelet count decreased to <10 x 10⁴/µL on the 13th day after the start of unfractionated heparin anticoagulation along with continuous hemodiafiltration, which was indicated for postoperative renal failure. The extracorporeal circuit clotted frequently under an adequate dose of unfractionated heparin. Serologically, heparin–platelet factor 4 complex antibodies were repeatedly detected by enzyme-linked immunosorbent assay. Argatroban, a direct thrombin inhibitor, was introduced as an alternative to unfractionated heparin, and the platelet count improved with a decrease in titers of the antibodies. Disseminated intravascular coagulation is a common complication in cases of abdominal aortic aneurysm and is usually treated in association with unfractionated heparin. It is important to recognize the onset of heparin-induced thrombocytopenia that acute declines in the platelet count and appearance of thrombosis with positive for heparin–platelet factor 4 complex antibodies would suddenly occur in clinical course of disseminated intravascular coagulation.

A 21-bp deletion mutation of the exon 11 of the myocyte enhancer factor-2A (MEF2A) gene was shown to cause familial coronary artery disease. This finding raises the possibility that MEF2A variants may contribute to the risk of coronary artery disease. In total, 258 patients with coronary artery disease and 258 controls were analyzed for the MEF2A variants. The analysis revealed that all patients were negative for Pro279Leu and 21-bp deletion mutations in exons 7 and 11, respectively. The distribution of the allele frequencies of MEF2A exon 11 CAG repeat (CAG)n polymorphism was similar in both patients and controls; Further, no significant association was noted between MEF2A exon 11 (CAG)n polymorphism and the risk of myocardial infarction. Our data suggest that there is no evidence of an association between the MEF2A exon 11 (CAG)n polymorphism and the risk of coronary artery disease/myocardial infarction in the Chinese population in Taiwan.

We studied the efficacy and safety of an investigational enoxaparin regimen, 1.5 mg/kg once daily, as a bridge to warfarin for the outpatient treatment of acute venous thromboembolism. We undertook a case-control design. We enrolled 40 acute venous thromboembolism cases prospectively and matched them by age, gender, and location of venous thromboembolism to 80 previously treated controls. All controls had received enoxaparin 1 mg/kg twice daily. The primary end point was recurrent venous thromboembolism. We followed the cases for 30 days. We discontinued enoxaparin after we achieved the target international normalized ratio between 2.0 and 3.0. One case (2.9%) and three controls (3.8%) had recurrent venous thromboembolic events (P = 1.00). There were no major bleeding complications in the case group, compared to 3 (3.8%) in the control group (P = .55). Once daily enoxaparin, 1.5 mg/kg, as a bridge to warfarin was as effective with a similar safety profile as twice daily enoxaparin, 1mg/kg, for initial treatment of acute venous thromboembolism in the outpatient setting. This case-control study provides the rationale for undertaking a randomized controlled trial comparing enoxaparin 1.5 mg/kg once daily versus enoxaparin 1.0 mg/kg twice daily as a bridge to warfarin in outpatients with acute venous thromboembolism.

Combined deficiency of the vitamin K-dependent clotting factors (VKCFD) is a rare bleeding disorder involving defective gamma-carboxylation of coagulation factors II , VII, IX and X as well as natural anticoagulants protein C and protein S. The disease is characterized by a cluster of different, often life threatening, bleeding symptoms occurring both spontaneously and in a surgical setting. In the present paper we describe two different treatment modalities to be used both in a programmed surgical procedure and in an emergency scenario. As this disease is a natural model that resembles oral anticoagulation, our experience discloses a possible rationale in the use of recombinant activated FVII for warfarin reversal.

Molecular imaging of thrombus formation at initial stage requires a robust thrombus-specific contrast agent with high sensitivity. In this study, we report a novel P-selectin-targeted paramagnetic molecular imaging agent and the agent's potential to sensitively detect occult microthrombi on the intimal surface of endothelium. Platelet clots and blood clots targeted in vitro with paramagnetic nanoparticles presented a highly detectable, homogeneous T1-weighted contrast enhancement that was improved with increasing gadolinium level. In vivo contrast enhancement under part of circulation conditions was assessed in dogs. The micro-thrombi around the femoral vein of dog demonstrated higher signal intensities than the control clots and the adjacent muscle. Histology was performed on regions likely to contain thrombus as indicated by MRI. These results suggest that molecular imaging of P-selectin-targeted paramagnetic nanoparticles can provide sensitive detection and localization of P-selectin and may allow for early, direct identification of micro-thrombi, leading to early diagnosis.

The aim of the study is to investigate whether the presence of a protein Z polymorphism is a risk factor for the development and outcome of sepsis. Sepsis is a clinical syndrome characterized by the presence of systemic signs and symptoms of inflammation. When sepsis leads to organ failure, the term severe sepsis and septic shock is used. The genetic causes of severe sepsis are not fully explained. Protein Z is a vitamin K–dependent glycoprotein and a member of the coagulation cascade. The study included 53 patients with severe sepsis and 70 control healthy volunteers without a familial history of thrombosis. The G79A polymorphism of intron F of the protein Z gene was analyzed by the method of polymerase chain reaction–based DNA analysis. The protein Z intron F G79A polymorphism frequencies of the patients and controls were 43.4% and 40%, respectively. Carrying 79 AA genotype could be a risk factor for severe sepsis and septic shock (OR = 4.5, 95% CI: 0.45-46.1), but it could not find any difference between survivor and nonsurvivor groups. They concluded that the frequency of intron F G79A polymorphism of protein Z gene was higher in patients than controls, and carrying 79 AA genotype could be a risk factor for severe sepsis and septic shock.

One class of oligonucleotides with a high potential for use in medical applications is short nucleic acids, widely known as aptamers. Although several aptamers are already being used clinically, there are very few studies dealing with the impact aptamers have on the hemostatic system. In this study, we have performed a comprehensive evaluation of the hemostatic system including coagulation, platelets, complement, and inflammatory activation by using different aptamer concentrations and fresh human whole blood in a well-established flow model. We found that single-stranded aptamers did not have a negative influence on platelets, complement, or inflammation but were able to activate factor XII, kallikrein, and prothrombin in a concentration-dependent manner. Consequently, the influence of aptamers on the coagulation system should be taken into consideration before the use of any aptamer-based drugs in patients.

Early initiation of heparin therapy for treatment of stroke is not only associated with an improved outcome, but also with the risk of hemorrhagic transformation. We compared the efficacy of three unfractionated heparin bolus regimens (0 U/kg, 30 U/kg, or 80 U/kg) in achieving a therapeutic activated partial thromboplastin time over the first 6-hour period in a cohort of 54 patients admitted with transient ischemic attack or stroke. Patients treated with the low bolus dose (30 U/kg) were more often within the therapeutic range for activated partial thromboplastin time at two hours after the initial bolus than patients treated with the other regimens. The percentage of therapeutic activated partial thromboplastin time results within the first six hours of treatment was greater in the group treated with the low bolus dose. Using the low bolus dose may reduce complication rates and improve clinical outcomes in the future clinical trials.

Anticoagulants used during percutaneous coronary intervention (PCI) should not only prevent coronary events, but also minimize the risk of periprocedural complications. Current anticoagulation therapies for PCI include unfractionated heparin (UFH), enoxaparin, fondaparinux, and bivalirudin. UFH and enoxaparin have good efficacy and safety profiles in PCI; furthermore, associated periprocedural complications such as catheter thrombosis are rare. Although newer anticoagulants seem safe and effective in patients with acute coronary syndromes, clinical trial data suggest that some pure factor Xa (FXa) inhibitors are associated with increased rates of catheter thrombosis, compared with heparin-based agents. Experimental systems show that polytherapeutic agents, including UFH and enoxaparin, are more effective anticoagulants than certain single-target agents. More studies are needed to assess whether catheter thrombosis is a class-, drug-, or dose-related effect, and how best to prevent it. Future trials should report the rates of periprocedural complications when assessing the safety of novel anticoagulation therapies in PCI.

It is unknown whether the glycosaminoglycan drug sulodexide interferes with transforming growth factor-β1—a member of heparin-binding family and a potent regulator of human biology and diseases. Hence, a 2-week pilot study was performed in 11 healthy men. Sulodexide was initially administered intravenously in a single dose, then—orally for 12 days and—again intravenously on study completion. Initial injection had no effect on activated form of the growth factor measured in plasma after 10 and 120 min; no change was also observed after 120 min from drug ingestion on day 7. On final intravenous administration, the growth factor levels increased by almost 60% after 10 min and remained elevated; the 120-min levels directly correlated with sulodexide dosage. Baseline cytokine levels decreased during the 2-week trial by more than 50%. In conclusion, transforming growth factor-β1 release and likely downregulation of its expression may constitute novel pharmacological effects of sulodexide.

A clot lysis time assay in which a tissue factor–induced fibrin clot is lysed by exogenously added tissue plasminogen activator has been recently reported. We evaluated the feasibility of clot lysis time in a routine hemostasis laboratory, and its correlation with thrombin activatable fibrinolysis inhibitor and plasminogen activator inhibitor-1 levels and changes with aging in 185 healthy participants. Clot lysis time was assessed by monitoring changes in turbidity during clot formation and subsequent lysis using a computerized kinetic spectrophotometric microtiter plate. After preliminary experiments, 100 and 160 ng/mL tissue plasminogen activator concentrations were chosen for the study. Clot lysis time was calculated by a new mathematical analysis of the lysis curve based on discrete derivative. Clot lysis time, thrombin activatable fibrinolysis inhibitor, and plasminogen activator inhibitor-1 plasma levels showed a normal distribution. For both concentrations of tissue plasminogen activator, clot lysis time progressively increased with increase in age (P < .0001) and was significantly correlated with thrombin activatable fibrinolysis inhibitor antigen, thrombin activatable fibrinolysis inhibitor activity, and plasminogen activator inhibitor-1 antigen (at least P < .01). During linear regression analysis, thrombin activatable fibrinolysis inhibitor and plasminogen activator inhibitor-1 antigen were found to significantly influence clot lysis time (at least P < .01). Clot lysis time determination has a good laboratory performance. Our new method of calculation is independent of the time of reading and allows a more accurate and consistent detection of both short and prolonged lysis times. Our data suggest the feasibility of the use of this test in the work of routine hemostasis laboratory.

Heparin-induced thrombocytopenia is a devastating, life-threatening, immune-mediated complication of therapy with unfractionated heparin, and less frequently, with low molecular weight heparin. Direct thrombin inhibitors are now standard therapy for the prevention of thrombosis in heparin-induced thrombocytopenia. Argatroban, a small synthetic molecule that inhibits thrombin at its active site, is increasingly used as the direct thrombin inhibitors of choice. Transition to longer term oral anticoagulation needs to be instituted after the platelet count has risen, because of the persistent risk of thrombosis. Although guidelines available in the literature outline the management of heparin-induced thrombocytopenia, they are not presented in a concise and comprehensive manner easily followed by physicians. This article reviews current recommendations, relevant studies, and clinical management trials carried out on patients with heparin-induced thrombocytopenia and provides updated, detailed guidelines for treatment of heparin-induced thrombocytopenia with emphasis on a key part of the management, the argatroban–warfarin transition.

Factor XI deficiency is a rare disease found predominantly in Ashkenazi Jews. There is a poor correlation between factor XI level and bleeding in patients with factor XI deficiency. Individuals with severe factor XI deficiency are usually at risk of excessive bleeding after surgery and injury, particularly when trauma involves tissues rich in fibrinolytic activity. Women with partial or severe deficiency are at risk of excessive uterine bleeding during labor. The unpredictable nature of factor XI deficiency complicates management during pregnancy and delivery. This review gives an overview of the management of pregnant women with factor XI deficiency.

Microparticles are small membrane vesicles released from activated cells and are associated with thrombosis and inflammation. Microparticles contain a unique subset of surface proteins derived from the parent cell and may be responsible for their diverse biological functions. To identify these proteins, juvenile baboons (Papio anubis, n = 4) underwent iliac vein thrombosis with 6-hour balloon occlusion. Plasma samples were taken at baseline and at 2 days postthrombosis for microparticle analysis. Microparticles were extracted from platelet-poor plasma, digested separately with trypsin and tagged using isobaric tagging for relative and absolute quantitation reagents. The digests were subjected to 2-dimensional liquid chromatographic separation followed by matrix-assisted laser desorption/ ionization tandem mass spectrometry. Peak lists were generated and searched against all primate sequences. For protein identity, a minimum of 2 peptides at 95% confidence interval was required. Later, isobaric tagging for relative and absolute quantitation ratios were generated comparing relative protein level of day 2 to baseline. The proteomic analysis was performed twice for each blood sample, totaling 8 experiments. Proteins were considered elevated or depressed if the isobaric tagging for relative and absolute quantitation ratio deviated by 20% change from normal and a P value less than .05. Significantly, 7 proteins were differentially expressed on day 2 compared to baseline, and appeared in at least 3 animals and regulated in at least 4 experiments. Among these 7 proteins, upregulated proteins include various forms of fibrinogen and -1-antichymotrypsin and downregulated proteins include immunoglobulins. These proteins influence thrombosis and inflammation through hemostatic plug formation (fibrinogen), inhibiting neutrophil adhesion (-1-antichymoptrypsin), and immunoregulation (immunoglobulins). Further studies are needed to confirm the mechanistic role of these proteins in the pathogenesis of venous thrombosis.

The transverse rectus abdominis muscle flap is widely used in free microvascular tissue transfer for breast reconstruction following mastectomy. Flap survival may be compromised by failure at the microsurgical anastomosis due to both venous and arterial thrombosis. It is unclear, whether hereditary thrombophilia represents a risk factor for early thrombotic occlusion following free flap procedures. We present a case of a patient with previously diagnosed activated protein resistance caused by heterozygous factor V (position 1691 G->A) Leiden mutation in whom a free transverse rectus abdominis muscle flap was performed. The postoperative course was complicated by repeated thrombosis of both the venous and arterial part of the anastomosis. Immediate thrombectomy and repeated arteriography allowed for partial flap salvage. More data are needed to analyze the impact of hereditary thrombophilia on microvascular anastomosis failure.

We present the case of a 19-year-old male athlete with protein C deficiency who developed proximal deep venous thrombosis and pulmonary embolism while abusing anabolic-androgenic steroids. Anabolic-androgenic steroids have been reported to have anticoagulatory and profibrinolytic effects in patients with protein C deficiency. Despite these antithrombotic effects, the patient developed repeated venous thromboembolism during treatment with low-molecular-weight heparin. The net effect of anabolic-androgenic steroids on the haemostatic system may change from antithrombotic to prothrombotic in male abusers of anabolic steroids with protein C deficiency.

Described is a case of acute chest syndrome in a sickle-cell patient (hemoglobin SS) who also developed signs and symptoms of thrombotic thrombocytopenic purpura, including thrombocytopenia and hemolysis (anemia, elevated lactate dehydrogenase, presence of schistocytes, dark-colored plasma, and elevations in nucleated red blood cells). The ADAMTS13 activity level was normal. Discussed are the diagnosis and therapeutic management issues and the challenges of differentiating the vasoocclusive and hemolytic complications of sickling red blood cells from the thrombotic microangiopathy of thrombotic thrombocytopenic purpura.