The Homozygous Type II Antithrombin Deficient Pregnant Woman Monitored by Thrombin Generation Assay.

BACKGROUND: We present the case study of a 28-year-old pregnant woman with antithrombin deficiency who was treated with low-molecular-weight heparin (LMWH). METHODS: Due to severe homozygous type II antithrombin heparin binding site (HBS) deficiency, the thrombin generation (TG) was monitored in this woman via the Thrombin Generation Assay (TGA). We used Siemens diagnostic kits Berichrom® Antithrombin III (IIa) and INNOVANCE® Antithrombin (Xa) to determine antithrombin activity. We used a chromogenic method for determination of factor Xa (FXa) inhibition. RESULTS: There were no thrombotic complications during the whole pregnancy of the observed woman. Antithrombin was administered before and after delivery, which was significantly reflected in the decrease in thrombin generation. CONCLUSIONS: Consistent monitoring of thrombin generation with LMWH anticoagulant therapy administration during pregnancy together with antithrombin administration before and after delivery can improve the overall condition of pregnant women and the quality of their care.

Thrombin Generation Decrease After LMWH Administration in an Antithrombin-Deficient Pregnant Woman With a Homozygous HBS II Mutation.

The cases of antithrombin (AT)-deficient pregnant women with a homozygous HBS II mutation are relatively rare and are accompanied by an increased thrombophilic risk, which is manifested by increased thrombin generation (TG). It is very difficult to ensure their prophylactic treatment during pregnancy. We aimed to determine the utility of the thrombin generation assay (TGA) and anti-factor Xa (anti-FXa) test to monitor the effects of a prophylactic dose of low-molecular-weight heparin (LMWH) in a 28-year-old woman with homozygous AT deficiency caused by mutation c.391C > T#, (p.Leu131Phe†) in the SERPINC1 gene and to compare the findings with those from a group of pregnant and non-pregnant women also treated with LMWH. TG monitoring was chosen due to severe AT deficiency that was manifested by low levels of anti-FXa activity when monitoring the efficacy of LMWH treatment. A significant decrease in TG was detected in all monitored groups (P < .05). There were no thrombotic complications during the whole pregnancy of the woman with AT deficiency. Consistent monitoring of TG with LMWH anticoagulant therapy administration during pregnancy together with AT administration before and after delivery may improve the overall condition of pregnant women and the quality of their care.

Thrombin Decrease in Thrombin Generation after Heparin Administration in a Homozygous Type II Heparin Binding Site Antithrombin-Deficient Pregnant Woman.

OBJECTIVES: There is a major problem in providing prophylactic treatment in antithrombin (AT)-deficient pregnant women with a homozygous mutation of the heparin binding site (HBS) and AT level of 17 %. The aim of the study was to determine the effectiveness of heparin by monitoring changes in thrombin generation (TG) in vitro so that pregnant women are not exposed to stress in vivo. METHODS: We used the chromogenic method for determination of factor Xa (FXa) inhibition for enoxaparine, nadroparine, dalteparine, fondaparinux and unfractionated heparin (UFH) and the Thrombin Generation Assay (TGA). RESULTS: We found that the degree of inhibition is very different when different heparins are compared. Nadroparin reduces TG the most compared to low molecular weight heparins (LMWH). CONCLUSION: Routine monitoring of anti FXa activity should be supplemented with TG monitoring, where the effect of LMWH does not manifest itself as this could help in estimating thrombophilic risk during pregnancy.

Today's view of hereditary thrombophilia.

Venous thromboembolism (VTE) is still a serious medical problem with the non-decreasing incidence of new cases despite prophylaxis in risky situations. It is a multifactorial disease, in which the hereditary component is also significantly involved. The aim of the current research is to search for new polymorphisms that are involved in thrombogenesis in addition to classical thrombophilia (deficiency of natural coagulation inhibitors and FVL and FII prothrombin mutations). The article provides an overview of the results of already performed genome-wide association studies of VTE and their use for the calculation of the so-called polygenic risk score, which could be used for individualized prevention of VTE after standardization of the method.

Rivaroxaban - Metabolism, Pharmacologic Properties and Drug Interactions.

BACKGROUND: Rivaroxaban represents a selective direct inhibitor of activated coagulation factor X (FXa) having peroral bioavailability and prompt onset of action. OBJECTIVE: The absorbtion of rivaroxaban is quick, reaching maximum plasma concentration 2-4 hours following its administration. Peroral bioavailability is high (80-100 %) and pharmacokinetic variability is considered to be moderate (coefficient of variation 30-40 %). This review discusses the properties, drug interactions, pharmacokinetics and clinical indications of rivaroxaban. METHOD: Dosing regimen of rivaroxaban was derived from pharmacologic data of the development program aimed to gain strong antithrombotic drug and balance between efficacy and risk of bleeding in patients. Results of doseranging trials, pharmacokinetic models and randomised studies of phase III advocate the use of such schemes in everyday practice. RESULTS: The drug has been manufactured to fulfill clinical requirements in a variety of indications in adults: prophylaxis of venous thromboembolism (VTE) following elective knee or hip replacement surgical intervention, therapy and secondary prophylaxis of VTE, prophylaxis of ischemic stroke and embolism in individuals diagnosed with nonvalvular atrial fibrillation (NVAF) with risky characteristics, and in Europe the prophylaxis of atherothrombotic episodes following an acute coronary syndrome in subjects with increased levels of cardiac biomarkers. CONCLUSION: Rivaroxaban may offer benefit in many clinical situations. In comparison with low molecular weight heparin and fondaparinux requiring subcutaneous way of administration, and with vitamin K antagonists (VKAs), which require regular monitoring of international normalized ratio, rivaroxaban is relatively easy to use. However, adjustments of dose are needed in individuals with impaired renal functions.

28 day post-operative persisted hypercoagulability after surgery for benign diseases: a prospective cohort study.

BACKGROUND: Surgery for benign disease is associated with a low-risk of developing venous thromboembolism (VTE). Despite a relatively low incidence of postoperative VTE in patients after elective cholecystectomy and abdominal hernia repair there are data proving hypercoagulability in the early postoperative period. We focused on assessment of the systemic inflammatory response and coagulation status in these surgical patients after hospital discharge. METHODS: Prospectively, patients who underwent surgery for benign disease were included. Two hundred sixteen patients were enrolled - 90 patients in laparoscopic cholecystectomy (LC) group and 126 patients in hernia surgery (HS) group. Risk assessment of VTE according to the Caprini risk assessment model was performed in all patients. Prevalence of VTE in postoperative period was observed. Markers of systemic inflammatory response (IL-6, CRP, α-1-acid glycoprotein, transferrin) and coagulation markers (PLT, fibrinogen, prothrombin fragment F1 + 2 and D-dimer) were measured before surgery, on 7-10th postoperative day and on 28-30th postoperative day. RESULTS: Clinically apparent deep vein thrombosis was diagnosed in only one patient - 0.46%. Statistically significant elevation of inflammatory markers IL-6, CRP and α-1-acid glycoprotein (p < 0.001; all) were proved in both groups of patients on 7-10th postoperative day. Statistically significant elevation of coagulation markers PLT, fibrinogen, prothrombin fragment F1 + 2 and D-dimer (p < 0.001; all) were proved in LC and HS groups on 7-10th postoperative day. No statistical difference was observed in IL-6, CRP and α-1-acid glycoprotein levels a month after surgery as compared with preoperative levels within each group. Statistically significant elevation of fibrinogen and prothrombin fragment F1 + 2 levels (p < 0.001; both) persisted on 28-30th postoperative day in both groups. Persisted elevation of D-dimer levels was proved only in HS group (p < 0.001), not in LC group (p = 0.138), a month after surgery. CONCLUSIONS: Activated systemic inflammatory response and hypercoagulable condition were verified in patients after laparoscopic cholecystectomy and hernia surgery after their hospital discharge. Hypercoagulability persisted even a month after surgery. Nevertheless, we observed very low prevalence of clinically apparent VTE in patients with in-hospital postoperative VTE prophylaxis. TRIAL REGISTRATION: Trials of the Czech Ministry of Health No. RVO-VFN64165 and NT 13251-4 .

Influence of long-term thromboprophylaxis with low-molecular-weight heparin (enoxaparin) on changes of bone metabolism markers in pregnant women.

This is a first descriptive, retrospective, observational study aiming to evaluate the changes in bone turnover markers in pregnant women and to assess the effect of a long-term treatment with low-molecular-weight heparin (LMWH), specifically, enoxaparin. Study involved 50 pregnant Caucasian women with thrombophilia. The patients either received prophylactic enoxaparin once daily subcutaneously (N = 35) or were observed without treatment (N = 15). Concentrations of total serum alkaline phosphatase (total AP), bone alkaline phosphatase (bone AP), osteoprotegerin (OPG), and the receptor activator of nuclear factor κB ligand (RANKL) were measured at 15, 25, and 35 weeks of gestation. Total serum AP increased with gestational age. In the group treated with enoxaparin, the percentage of bone AP concentration was lower (P < .05) than in the control group. Serum OPG also increased with gestational age, but no significant difference was found between the groups with- and without treatment. Despite the OPG increased, RANKL did not change.

FXa inhibition and coagulation changes during DVT prophylaxis by enoxaparin over the course of a 15-day follow-up in septic patients.

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], D-dimer, fragment 1.2 [F1.2], factor Xa [FXa] inhibition) and inflammatory reactants (interleukin 6 [IL-6], C-reactive protein [CRP], orosomucoid, alpha-1-antitrypsin) were tested. The mean FXa inhibition was 0.17 (+ or - 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 alpha-1-antitrypsin concentrations (r = -.33; P = .01) but only in the subgroup with alpha-1-antitrypsin concentrations > or = 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.

Favorable coagulation profile with fondaparinux after hip surgery in elderly patients.

Twenty-three patients with fondaparinux prophylaxis over 75 years of age who underwent hip fracture surgery were enrolled in the study. Fondaparinux sodium (2.5 mg) was administered subcutaneously 6 h postoperatively and then every 24 h for 28 days. Coagulation and inflammatory parameters were measured preoperatively, then 10 h, 2, 7, and 28 days postoperatively. Increased D-dimers, positive acute phase proteins, and IL-6, and decreased negative acute phase proteins were observed preoperatively (P < 0.05). Maximum values were reached 10 h postoperatively for IL-6 and D-dimer, and on postoperative days 2 and 7 for positive acute phase proteins (P < 0.05). Transferrin, prealbumin and antithrombin levels were lowest 10 h postoperatively and on postoperative day 2 (P < 0.05). Increased D-dimers, IL-6, and positive acute phase proteins, and decreased negative acute phase proteins persisted until postoperative day 28 (P < 0.05). Prothrombin fragments (F1 + 2) reached peak levels preoperatively and decreased gradually until postoperative day 28. Fondaparinux promoted the inhibition of thrombin generation, as documented by negative correlation between F1 + 2 and FXa inhibition (r = -0.46; P < 0.001). Fondaparinux-induced FXa inhibition increased gradually until postoperative day 28. This increase correlated positively with antithrombin activity (r = 0.4; P < 0.05). Fondaparinux prophylaxis counteracted pro-thrombogenic effect associated with hip fracture and subsequent surgery without severe bleeding complications.