Thrombosis and hemostasis health in pregnancy: Registries from the International Society on Thrombosis and Haemostasis

Management of Postpartum Extensive Venous Thrombosis after Second Pregnancy

Background: Pregnancy induces a physiological prothrombotic state. The highest risk period for venous thromboembolism and pulmonary embolism in pregnant women is during the postpartum period. Materials and Methods: We present the case of a young woman who gave birth 2 weeks before admission and was transferred to our clinic for edema. She had an increased temperature in her right limb, and a venous Doppler of the limb confirmed thrombosis of the right femoral vein. From the paraclinical examination, we obtained a CBC with leukocytosis, neutrophilia, and thrombocytosis, and a positive D-dimer test. Thrombophilic tests were negative for AT III, lupus anticoagulant negative, and protein S and C, but were positive for heterozygous PAI-1, heterozygous MTHFR A1298C, and EPCR with A1/A2 alleles. After 2 days of UFH with therapeutic APTT, the patient had pain in her left thigh. We performed a venous Doppler, which revealed bilateral femoral and iliac venous thrombosis. During the computed tomography examination, we assessed the venous thrombosis extension on the inferior cava, common iliac, and bilateral common femoral veins. Thrombolysis was initiated with 100 mg of Alteplase given at a rate of 2 mg/h; however, this did not lead to a considerable reduction in the thrombus. Additionally, the treatment with UFH was continued under therapeutic APTT. After 7 days of UFH and triple antibiotic therapy for genital sepsis, the patient had a favorable evolution with remission of venous thrombosis. Results: Alteplase is a thrombolytic agent that is created with recombinant DNA technology, and it was successfully used to treat thrombosis that occurred in the postpartum period. Conclusions: Thrombophilias are associated with a high VTE risk but also with adverse pregnancy outcomes, including recurrent miscarriages and gestational vascular complications. In addition, the postpartum period is associated with a higher VTE risk. A thrombophilic status with heterozygous PAI-1, heterozygous MTHFR A1298C, and EPCR with A1/A2 positive alleles is associated with a high risk of thrombosis and cardiovascular events. Thrombolysis can be successfully used postpartum to treat VTEs. Thrombolysis can be used successfully in VTE developed in the postpartum period.

Proteomics Studies in Gestational Diabetes Mellitus: A Systematic Review and Meta-Analysis

Gestational Diabetes Mellitus (GDM) is the most common metabolic complication during pregnancy and is associated with serious maternal and fetal complications such as pre-eclampsia and stillbirth. Further, women with GDM have approximately 10 times higher risk of diabetes later in life. Children born to mothers with GDM also face a higher risk of childhood obesity and diabetes later in life. Early prediction/diagnosis of GDM leads to early interventions such as diet and lifestyle, which could mitigate the maternal and fetal complications associated with GDM. However, no biomarkers identified to date have been proven to be effective in the prediction/diagnosis of GDM. Proteomic approaches based on mass spectrometry have been applied in various fields of biomedical research to identify novel biomarkers. Although a number of proteomic studies in GDM now exist, a lack of a comprehensive and up-to-date meta-analysis makes it difficult for researchers to interpret the data in the existing literature. Thus, we undertook a systematic review and meta-analysis on proteomic studies and GDM. We searched MEDLINE, EMBASE, Web of Science and Scopus from inception to January 2022. We searched Medline, Embase, CINHAL and the Cochrane Library, which were searched from inception to February 2021. We included cohort, case-control and observational studies reporting original data investigating the development of GDM compared to a control group. Two independent reviewers selected eligible studies for meta-analysis. Data collection and analyses were performed by two independent reviewers. The PROSPERO registration number is CRD42020185951. Of 120 articles retrieved, 24 studies met the eligibility criteria, comparing a total of 1779 pregnant women (904 GDM and 875 controls). A total of 262 GDM candidate biomarkers (CBs) were identified, with 49 CBs reported in at least two studies. We found 22 highly replicable CBs that were significantly different (nine CBs were upregulated and 12 CBs downregulated) between women with GDM and controls across various proteomic platforms, sample types, blood fractions and time of blood collection and continents. We performed further analyses on blood (plasma/serum) CBs in early pregnancy (first and/or early second trimester) and included studies with more than nine samples (nine studies in total). We found that 11 CBs were significantly upregulated, and 13 CBs significantly downregulated in women with GDM compared to controls. Subsequent pathway analysis using Database for Annotation, Visualization and Integrated Discovery (DAVID) bioinformatics resources found that these CBs were most strongly linked to pathways related to complement and coagulation cascades. Our findings provide important insights and form a strong foundation for future validation studies to establish reliable biomarkers for GDM.

Pulmonary Embolism and Pregnancy-Challenges in Diagnostic and Therapeutic Decisions in High-Risk Patients

Diagnosis of acute PE in pregnant women with haemodynamic instability is following the general integrated risk-adapted diagnostic algorithm and starts with bedside echocardiography to assess RV function. If RV dysfunction is identified, a prompt and immediate reperfusion without further imaging should be initiated. Although pregnancy is listed as a relative contraindication of systemic thrombolysis, in pregnant women with acute PE and haemodynamic instability thrombolysis must be considered. In those cases, other treatment strategies as surgical embolectomy or catheter-directed low-dose thromboylysis or percutaneous thrombectomy should be taken into consideration as well. A multidisciplinary team with experience of PE management in pregnancy should be consulted to reach consensus on the best treatment approach.

Prophylaxis and management of venous thromboembolism during pregnancy and postpartum period

Introduction. Venous thromboembolism (VTE) is one of the lead causes for maternal mortality and morbidity during pregnancy in the majority of developed countries. The incidence rate of VTE per pregnancy-year increases during pregnancy and postpartum period about by 4-fold and at least 14-fold, respectively.

Aim: to analyze and summarize current view on risk factors of thrombotic events during gestation and to discuss recent guidelines for the management of venous thromboembolic complications during pregnancy and postpartum, by taking into account a balance between risks and benefits of using anticoagulants.

Materials and Methods. The literature search covering the last 10 years was carried out in the electronic scientific databases RSCI, PubMed/MEDLINE, and Embase. While formulating a search strategy for evidence-based information, the PICO method (P = Patient; I = Intervention; C = Comparison; O = Outcome) and the key terms “venous thromboembolism” and “pregnancy” were used.

Results. Risk factors were found to include a personal history of VTE, verified inherited or acquired thrombophilia, a family history of VTE and general medical conditions, such as immobilization, overweight, varicose veins, some hematological diseases and autoimmune disorders. VTE is considered being potentially preventable upon prophylactic administration of anticoagulants, but no high confidence randomized clinical trials comparing diverse strategies of thromboprophylaxis in pregnant women have been proposed so far. Because heparins do not cross the placenta, weight-adjusted therapeutic-dose low molecular weight heparins (LMWH) represent the anticoagulant treatment of choice for VTE during pregnancy. Once- and twice-daily dosing regimens are acceptable. However, no evidence suggesting benefits for measurement of factor Xa activities and consecutive LMWH dose adjustments to improve clinical outcomes are available. In case of uncomplicated pregnancy-related VTE, no routine administration of vitamin K antagonists, direct thrombin or factor Xa inhibitors, fondaparinux, or danaparoid is recommended. Lactating women may switch from applying LMWH to warfarin. Anticoagulation therapy should be continued for 6 weeks postpartum with total duration lasting at least for 3 months.

Conclusion. VTE is a challenging task in pregnant women expecting to apply a multi-faceted approach for its efficient solution by taking into account updated recommendations and personalized patient-oriented features.

Immunological and physiopathological approach of COVID-19 in pregnancy

Coronavirus disease-2019 (COVID-19) related to Coronavirus-2 (SARS-CoV-2) is a worldwide health concern. Despite the majority of patients will evolve asymptomatic or mild-moderate upper respiratory tract infections, 20% will develop severe disease. Based on current pathogenetic knowledge, a severe COVID-19 form is mainly a hyperinflammatory, immune-mediated disorder, triggered by a viral infection. Due to their particular immunological features, pregnant women are supposed to be particularly susceptible to complicate by intracellular infections as well as immunological disturbances. As an example, immune-thrombosis has been identified as a common immune-mediated and pathogenic phenomenon both in COVID-19, in obstetric diseases and in COVID-19 pregnant women. According to extensive published clinical data, is rationale to expect an interference with the normal development of pregnancy in selected SARS-CoV-2-infected cases, mainly during third trimester.This manuscript provides insights of research to elucidate the potential harmful responses to SARS-CoV-2 and /or other coronavirus infections, as well as bidirectional interactions between COVID-19 and pregnancy to improve their respective management.

Management of high-risk pulmonary embolism in pregnancy

Pregnancy-associated high-risk pulmonary embolism (PE) is among the most frequent causes of maternal mortality in the Western world, by causing hemodynamic instability and circulatory failure through a large thrombotic pulmonary obstruction. The very challenging management of these dramatic situations comprises the need to quickly select a therapy of pulmonary reperfusion or hemodynamic replacement, while taking into account both maternal and fetal risks. In this review, we discuss the role of risk stratification in pregnancy-associated PE and the available evidence to support the use of thrombolysis, catheter-directed thrombectomy/thrombolysis, surgical embolectomy and extracorporeal membrane oxygenation. Despite the lack of comparative studies and solid evidence, most reported cases of high-risk pregnancy-associated PE have been treated with thrombolysis, with high maternal and fetal survivals, and thrombolysis is suggested by guidelines in life-threatening PE. For women in the peripartum and early post-partum period, non-fibrinolytic treatments may be preferred as a first-line treatment, if available, because of the particularly high bleeding risk. In all cases, pregnancy-associated high-risk PE requires a multidisciplinary approach involving PE response teams and obstetricians.

How I treat venous thromboembolism in pregnancy

One to 2 pregnant women in 1000 will experience venous thromboembolism (VTE) during pregnancy or postpartum. Pulmonary embolism (PE) is a leading cause of maternal mortality, and deep vein thrombosis leads to maternal morbidity, with postthrombotic syndrome potentially diminishing quality of life for a woman's lifetime. However, the evidence base for pregnancy-related VTE management remains weak. Evidence-based guideline recommendations are often extrapolated from nonpregnant women and thus weak or conditional, resulting in wide variation of practice. In women with suspected PE, the pregnancy-adapted YEARS algorithm is safe and efficient, rendering computed tomographic pulmonary angiography to rule out PE unnecessary in 39%. Low molecular weight heparin (LMWH) in therapeutic doses is the treatment of choice during pregnancy, and anticoagulation (LMWH or vitamin K antagonists [VKAs]) should be continued until 6 weeks after delivery, with a 3-month minimum total duration. LMWH or VKA use does not preclude breastfeeding. Postpartum, direct oral anticoagulants are an option if a woman does not breastfeed and long-term use is intended. Management of delivery, including type of analgesia, requires a multidisciplinary approach and depends on local preferences and patient-specific conditions. Several options are possible, including waiting for spontaneous delivery with temporary LMWH interruption. Prophylaxis for recurrent VTE prevention in subsequent pregnancies is indicated in most women with a history of VTE.

Ionotropic glutamate receptors in platelets: opposing effects and a unifying hypothesis

Ionotropic glutamate receptors include α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPAR), kainate receptors (KAR), and N-methyl-D-aspartate receptors (NMDAR). All function as cation channels; AMPAR and KAR are more permeable to sodium and NMDAR to calcium ions. Compared to the brain, receptor assemblies in platelets are unusual, suggesting distinctive functionalities.There is convincing evidence that AMPAR and KAR amplify platelet function and thrombus formation in vitro and in vivo. Transgenic mice lacking GluA1 and GluK2 (AMPAR and KAR subunits, respectively) have longer bleeding times and prolonged time to thrombosis in an arterial model. In humans, rs465566 KAR gene polymorphism associates with altered in vitro platelet responses suggesting enhanced aspirin effect. The NMDAR contribution to platelet function is less well defined. NMDA at low concentrations (≤10 μM) inhibits platelet aggregation and high concentrations (≥100 μM) have no effect. However, open NMDAR channel blockers interfere with platelet activation and aggregation induced by other agonists in vitro; anti-GluN1 antibodies interfere with thrombus formation under high shear rates ex vivo; and rats vaccinated with GluN1 develop iron deficiency anemia suggestive of mild chronic bleeding. In this review, we summarize data on glutamate receptors in platelets and propose a unifying model that reconciles some of the opposing effects observed.

Safety of direct oral anticoagulant exposure during pregnancy: a retrospective cohort study

BACKGROUND

Direct oral anticoagulants (DOACs) have largely replaced vitamin K antagonists in many indications for anticoagulation. Prescribed to millions of patients, including women of reproductive age, exposure to DOACs in early pregnancy is not uncommon, but data on the embryotoxic risks are scarce. We aimed to assess the risk of DOAC embryotoxicity in a large sample of reported cases.

METHODS

In this retrospective cohort study, we collected individual case reports of DOAC exposure in pregnancy from gynaecologists, haematologists, and vascular specialists starting from May, 2015. We obtained exports in April and October, 2017, August, 2018, and December, 2019, from the pharmacovigilance databases of the DOAC manufacturers, the European Medicines Agency (EMA), the German drug authority, and searched the homepage of the US Food and Drug Administration (FDA) for pregnancy exposure reports. Data from the International Society of Thrombosis and Haemostasis (ISTH) registry were obtained in August, 2018, and on July 21, 2020; data from the Teratology Information Service in Ulm, Germany, were received July 22, 2020. We also ran a systematic literature search on July 22, 2020, for cases of DOAC exposure. These data were compiled with those from our 2016 risk assessment and duplicate reports were excluded. Fetal or neonatal abnormalities were classified as a major birth defect according to the European Concerted Action on Congenital Anomalies and Twins (EUROCAT) classification and adjudicated into four categories: relation to DOAC exposure likely, possible, unlikely, or unrelated.

FINDINGS

We identified 1193 reports of DOAC exposure during pregnancy: 49 from physicians, 48 from the ISTH registry, 29 from the Teratology Information Service, 62 from the German drug authority, 536 from Bayer (extracted from the Bayer pharmacovigilance system, the WHO VigiBase, and from the FDA Adverse Event Reporting System), 87 from Boehringer Ingelheim, 16 from Daiichi Sankyo, 98 from the literature search, two from the FDA homepage search, ten from the Risk Evaluation and Mitigation Strategy Review, and 256 from the EMA reports. After excluding potential duplicates, we identified 614 unique cases of DOAC exposure in pregnancy occurring between Feb 1, 2007, and July 9, 2020, that consisted of rivaroxaban in 505 (82%) pregnancies, dabigatran in 36 (6%), apixaban in 50 (8%), and edoxaban in 23 (4%). The median duration of DOAC exposure was 5·3 weeks (IQR 4·0-7·0) into pregnancy. Information on pregnancy outcome was available in 336 (55%) of 614 pregnancies: 188 (56%) livebirths, 74 (22%) miscarriages, and 74 (22%) elective pregnancy terminations. 21 (6%; 95% CI 4-9) of 336 showed fetal abnormalities, of which 12 (4%; 2-6) were adjudicated as major birth defects potentially related to DOAC exposure.

INTERPRETATION

Although reports of pregnancy outcomes after DOAC exposure are missing important details and predominantly describe rivaroxaban exposures, the available data do not suggest that DOAC exposure in pregnancy carries a high risk of embryopathy. The 2016 ISTH guidance against elective pregnancy termination for fear of DOAC embryotoxicity and the recommendation in favour of close pregnancy surveillance is still valid. Pregnancy outcome data are inconsistently captured in pharmacovigilance databases, indicating a strong need for a more robust system of reporting.

FUNDING

None.

Placental abruption as a trigger of DIC in women with HELLP syndrome: a population-based study

BACKGROUND

Disseminated Intravascular Coagulation (DIC) is a life-threatening condition. Hemolysis, Elevated Liver enzymes and Low Platelets (HELLP) syndrome is one of the obstetrical syndromes mostly associated with DIC and thus, high rates of fatal complications. There is a lack of information regarding epidemiologic and clinical characteristics of women who developed HELLP syndrome with and without DIC. Additionally, until now, there is no adapted and widely accepted way to diagnose DIC among pregnant women presenting with HELLP syndrome, despite the evident maternal mortality linked to the disease.

Objectives: (1) Address the gaps in knowledge regarding the prevalence, epidemiologic and clinical characteristics of women with HELLP syndrome who develop DIC; and (2) determine the risk factors for the development of DIC among women with HELLP syndrome.

STUDY DESIGN

This was a population-based retrospective cohort study, including all women who delivered at the Soroka University Medical Center between the years 2001-2017. The study population was divided into three groups: (1) comparison group (n = 207,266 deliveries); (2) HELLP syndrome without DIC (n = 320); (3) HELLP syndrome with DIC (n = 21). The diagnosis of DIC was based on the ICD-9 code as recorded in the obstetrical database of the Soroka University Medical Center. The coding is based on the diagnosis made by the attending physician during hospitalization.

RESULTS

(1) The rate of HELLP syndrome in the study population was 0.16% (341/207,607), of them 6.16% (21/341) had DIC; (2) among patients with HELLP syndrome, those with DIC had a higher median gravidity and parity; (3) a higher rate of severe maternal morbidity including blood product transfusion, placental abruption, eclampsia, acute renal failure and maternal death was observed in those who had HELLP syndrome and DIC compared to those with HELLP syndrome without DIC and the comparison group (p-value <.001 for comparison among the three groups); (4) among women with HELLP syndrome, those with DIC had a longer median PT difference, higher serum creatinine and lower AST as well as ALT median concentrations than those without DIC; (5) patients with HELLP syndrome and DIC had a higher rate of stillbirth and postpartum death than patients in the other groups (p-value <.001 for comparison among the three groups); and (6) placental abruption was an independent risk factor for the development of DIC in women with HELLP syndrome (p-value <.001).

CONCLUSIONS

(1) Among women with HELLP syndrome, those who developed DIC had a higher rate of maternal and neonatal morbidity and mortality than those without DIC; and (2) placental abruption, but not abnormal liver function, was an independent risk factor for the development of DIC in women with HELLP syndrome.