Thrombophilia, Thrombosis and Thromboprophylaxis in Pregnancy: For What and in Whom?

Scanning optoacoustic angiography for assessing structural and functional alterations in superficial vasculature of patients with post-thrombotic syndrome: A pilot study

This study highlights the potential of scanning optoacoustic angiography (OA) in identifying alterations of superficial vasculature in patients with post-thrombotic syndrome (PTS) of the foot, a venous stress disorder associated with significant morbidity developing from long-term effects of deep venous thrombosis. The traditional angiography methods available in the clinics are not capable of reliably assessing the state of peripheral veins that provide blood outflow from the skin, a key hallmark of personalized risks of PTS formation after venous thrombosis. Our findings indicate that OA can detect an increase in blood volume, diameter, and tortuosity of superficial blood vessels. The inability to spatially separate vascular plexuses of the dermis and subcutaneous adipose tissue serves as a crucial criterion for distinguishing PTS from normal vasculature. Furthermore, our study demonstrates the ability of scanning optoacoustic angiography to detect blood filling decrease in an elevated limb position versus increase in a lowered position.

Evaluating Thromboprophylaxis Strategies for High-Risk Pregnancy: A Current Perspective

Venous thromboembolism (VTE) represents one of the leading causes of death during pregnancy. The greatest risk for it is the presence of medical or family history of VTE, stillbirth, cesarean section and selected thrombophilia. Appropriate thromboprophylaxis has the potential to decrease the risk of VTE in at-risk pregnant patients by 60-70%. Based on this, the authors reviewed the PubMed, Web of Science and Scopus databases to identify the possibilities of thromboprophylaxis in pregnant patients with a high risk of VTE. Moreover, they summarized its management in specific situations, such as cesarean delivery or neuraxial blockade. Currently, low-molecular-weight heparins (LMWH) are the preferred drugs for anticoagulant thromboprophylaxis in the course of pregnancy and postpartum due to easy administration and a lower rate of adverse events.

Guideline for diagnosis and management of congenital dysfibrinogenemia

INTRODUCTION

Congenital dysfibrinogenemia (CD) is characterized by dysfunction induced by an abnormal fibrinogen molecule structure that results in blood coagulation dysfunction. The clinical manifestations of CD patients are asymptomatic, bleeding and thrombosis. The majority of patient are asymptomatic. However, the single fibrinogen detection method is easy to cause missed diagnosis or misdiagnosis of CD patients. The treatment strategies of CD patients with different clinical manifestations are also different.

METHODS

Combing the existing experimental diagnosis technology, literature and our research results, a simple and practical CD diagnostic criteria was proposed. And based on the relevant literature and existing treatment guidelines, more comprehensive treatment recommendations are summarized.

RESULTS

In this new criteria, combination Clauss method and PT derived method was proposed to detect fibrinogen and its ratio was used to diagnose for CD. Diagnosis also needs to be combined the clinical manifestations, family investigation and genetic testing. According to different clinical manifestation (bleeding, thrombosis or asymptomatic), treatment methods and strategies are different. The treatment of CD patients should consider the patient's personal and family history of bleeding or thrombosis. Treatment of thrombosis and pregnancy may be more challenging. The risk of bleeding and thrombosis should be evaluated and balanced at all times during clinical treatment. These detailed treatment recommendations can provide reference for patients with different clinical manifestations of CD.

CONCLUSIONS

The new CD diagnosis criteria and comprehensive treatment recommendations can effectively improve the diagnosis and treatment of CD.

Venous Thromboembolism Risk Factors in Women With Obesity Who Undergo Cesarean Delivery

Venous thromboembolism (VTE) is a leading cause of maternal mortality. Obesity and cesarean delivery are established risk factors for pregnancy-related VTE. We identified additional risk factors among patients with obesity who underwent a cesarean delivery to identify those who need VTE prophylaxis. We conducted a secondary analysis of data from the Maternal-Fetal Medicine Units Network (MFMU) Cesarean Registry Database using a case-control design. Cases were identified as women with obesity having a pre-pregnancy body mass index of >30 kg/m2, who underwent cesarean delivery and subsequently developed deep venous thrombosis (DVT) or pulmonary embolism (PE). These women were compared to a control group of women with obesity who underwent cesarean delivery but did not develop DVT or PE. Analysis of risk factors associated with VTE was performed using Chi-Square test and Fisher's exact test. We identified 43 VTE cases and 172 controls in the MFMU database. Increased risk of VTE was noted in women with endometritis (OR of 4.58 [95% CI: 1.86-11.2, P = .0004]), receiving a blood transfusion (OR 17.07 [95% CI: 4.46-65.3, P = .0001]), having a coagulopathy (OR 27.73 [95% CI: 3.24-237.25, P = .0003]), and urinary tract infection (OR 2.39 [95% CI: 1.08-5.28, P = .03]). Important risk factors for VTE in women with obesity who undergo cesarean delivery include endometritis, intra- or post-operative transfusion, coagulopathy, and urinary tract infection. The presence of one or more of these factors may help guide provider decision-making regarding whether to administer thromboprophylaxis.

Efficacy and safety of therapies for COVID-19 in pregnancy: a systematic review and meta-analysis

BACKGROUND

Clinical evidence suggests that pregnant women are more vulnerable to COVID-19, since they are at increased risk for disease progression and for obstetric complications, such as premature labor, miscarriage, preeclampsia, cesarean delivery, fetal growth restriction and perinatal death. Despite this evidence, pregnant women are often excluded from clinical trials, resulting in limited knowledge on COVID-19 management. The aim of this systematic review and meta-analysis is to provide better evidence on the efficacy and safety of available COVID-19 treatment in pregnant women.

METHODS

Four authors searched major electronic databases from inception until 1 st November-2022 for controlled trials/observational studies, investigating outcomes after the administration of anti-SARS-CoV-2 treatments in pregnant women affected by COVID-19. The analyses investigated the cumulative incidence of delivery and maternal outcomes in pregnant women, comparing those taking active medication vs standard care. Risk ratios (RRs) with 95% confidence intervals were calculated. Statistical significance was assessed using the random effects model and inverse-variance method. This systematic review and meta-analysis was conducted in accordance with the updated 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The protocol has been registered in Prospero (number registration: CRD42023397445).

RESULTS

From initially 937 non duplicate records, we assessed the full texts of 40 articles, finally including ten studies. In six studies, including 1627 patients, the use of casirivimab/imdevimab (CAS/IMD), remdesivir, and IFN-alpha 2b significantly decreased the need of cesarean section ((RR = 0.665; 95%CI: 0.491-0.899; p = 0.008; I 2 = 19.5%;) (Table 1, (Fig. 1). Treatments did not decrease the risk of preterm delivery, admission to neonatal ICU, or stillbirth/perinatal loss (p-values > 0.50 for all these outcomes) and did not prevent the progression of disease towards severe degrees (k = 8; 2,374 pregnant women; RR = 0.778; 95%CI: 0.550-1.099; p = 0.15; I 2 = 0%). Moreover, the use of medications during pregnancy did not modify the incidence of maternal death in two studies (Table 2).

CONCLUSIONS

To our analysis, CAS/IMD, remdesivir, and IFN alpha 2b reduced the number of cesarean sections but demonstrated no effect on disease progression and other obstetric and COVID-19 related outcomes. The inability to evaluate the influence of viral load on illness development in pregnant women was attributed to lack of data. In our systematic review, no major side effects were reported. Though, it is essential for the medical community to focus more on clinical trials and less on episodic case reports and case series, with standardization of fetal and maternal outcomes.

Multiple sclerosis and pregnancy: Pathogenesis, influencing factors, and treatment options

Multiple sclerosis (MS) is an autoimmune-mediated degenerative disease of the central nervous system, characterized by inflammatory demyelination. It is primarily found in women of childbearing age, making pregnancy a significant concern for both patients with MS and clinicians. To assist these patients in achieving their desire for pregnancy, reducing MS relapses during all stages of pregnancy, preventing the progression of MS, mitigating the impact of MS treatment on the course and outcome of pregnancy, and a thorough understanding of the relationship between pregnancy and MS, as well as specific management and the application of relevant medications for MS patients at each stage of pregnancy, are essential. This article provides an update on pregnancy-related issues in women with MS, including the general recommendations for management at each stage of pregnancy.

Incidence of Pregnancy-Associated Venous Thromboembolism: Second Nationwide Study

BACKGROUND

 Pregnancy is a transient risk factor for venous thromboembolism (VTE). This second nationwide study aimed to inspect trend changes in the incidence rate of pregnancy-associated VTE (PA-VTE) during the study period (2014-2018) compared with that reported in a previous study (2006-2010).

METHODS

 Using the Korean Health Insurance Review and Assessment Service database, we retrospectively identified all PA-VTE events using both diagnostic and medication codes.

RESULTS

 Of the 124,228 VTE events, 510 (0.4%) cases of PA-VTE were identified in 499 women (median age: 34 years; range: 20-49 years). The incidence rate of PA-VTE/10,000 deliveries (PA-VTE/104D) in this second study (2.62) was 3.2 times higher than that in the first study (0.82). In the second study, the PA-VTE/104D ratio of women in their 40s (5.46) was three times higher than that of women in their 20s (1.80) (relative risk: 3.03; 95% confidence interval: 2.04-4.51; p < 0.01). The incidence rate for women in their 40s in the second study was 2.3 times higher than that in the first study. PA-VTE/104D cases occurred more frequently in multiparous than in primiparous women, in cesarean section cases compared with vaginal delivery, and in multiple rather than single pregnancies. Most PA-VTE cases occurred during the postpartum period (321/510, 62.9%), of which pulmonary embolism was the most frequently occurring type (231/321, 72%).

CONCLUSION

 Advanced maternal age, cesarean section, multiparity, and multifetal pregnancies increased the risk of PA-VTE. Obstetricians need to be cautious of VTE, particularly during the postpartum period, in high-risk pregnant patients.

Venous thromboembolism risk score during hospitalization in pregnancy: results of 10694 prospective evaluations in a clinical trial

OBJECTIVES

Hospitalization during pregnancy and childbirth increases the risk of Venous Thromboembolism Risk (VTE). This study applied a VTE risk score to all hospitalized pregnant women to ascertain its effectiveness in preventing maternal death from VTE until 3 months after discharge.

METHODS

In this interventional study, patients were classified as low- or high-risk according to the VTE risk score (Clinics Hospital risk score). High-risk patients (score ≥ 3) were scheduled for pharmacological Thromboprophylaxis (TPX). Interaction analysis of the main risk factors was performed using Odds Ratio (OR) and Poisson regression with robust variance.

RESULTS

The data of 10694 cases (7212 patients) were analyzed; 1626 (15.2%, 1000 patients) and 9068 (84.8%, 6212 patients) cases were classified as high-risk (score ≥ 3) and low-risk (score < 3), respectively. The main risk factors (Odds Ratio, 95% Confidence Interval) for VTE were age ≥ 35 and < 40 years (1.6, 1.4-1.8), parity ≥ 3 (3.5, 3.0-4.0), age ≥ 40 years (4.8, 4.1-5.6), multiple pregnancies (2.1, 1.7-2.5), BMI ≥ 40 kg/m² (5.1, 4.3-6.0), severe infection (4.1, 3.3-5.1), and cancer (12.3, 8.8-17.2). There were 10 cases of VTE: 7/1636 (0.4%) and 3/9068 (0.03%) in the high- and low-risk groups, respectively. No patient died of VTE. The intervention reduced the VTE risk by 87%; the number needed to treat was 3.

CONCLUSIONS

This VTE risk score was effective in preventing maternal deaths from VTE, with a low indication for TPX. Maternal age, multiparity, obesity, severe infections, multiple pregnancies, and cancer were the main risk factors for VTE.

Extensive Postpartum Upper and Lower Extremity Deep Vein Thrombosis in a Patient With a History of Preeclampsia

We describe the case of a 19-year-old woman with no significant medical history who developed progressive right-sided neck pain and palpitations one month following a pregnancy complicated by preeclampsia. Family history was significant for unprovoked deep vein thrombosis (DVT) and pulmonary embolism (PE) in her father at age 44. Systemic examination revealed mild swelling of the right upper extremity with pain on palpation. Computed tomography (CT) of the thorax with contrast demonstrated extensive occlusion of right upper extremity veins and collateralization of chest wall veins. Pulmonary emboli were present bilaterally in the segmental and subsegmental branches of the lower lobe pulmonary arteries. CT of the abdomen with contrast revealed thrombi in the left common and external iliac veins. Thrombophilia screening was normal. The patient was treated with enoxaparin and ampicillin/sulbactam. Her clinical condition improved, and she was discharged with an outpatient clinic follow-up appointment.

Pregnancy outcomes and adverse events in patients with recurrent miscarriage receiving fondaparinux versus low molecular-weight heparin: A meta-analysis

OBJECTIVE

Current opinion on the superiority of fondaparinux versus low molecular-weight heparin (LMWH) in treating recurrent miscarriage is controversial. This meta-analysis aimed to comprehensively compare the pregnancy outcomes and adverse events in patients with recurrent miscarriage receiving fondaparinux versus LMWH.

METHODS

EMBASE, PubMed, Cochrane, China National Knowledge Internet (CNKI), Wanfang Database, and China Science and Technology Journal Database (CQVIP) databases were searched for articles reporting fondaparinux versus LMWH in treating recurrent miscarriage till June 10, 2022. Inclusion criteria for study screening were: (i) randomized, controlled trials (RCT), non-randomized controlled studies, or observational studies; (ii) patients aged over 18 years; (iii) patients with recurrent miscarriage during gestation period; (iv) patients in the experimental/observational group who received FD, and patients in the control group who received LMWH; (v) studies involving at least one outcome of interest for the current analysis. Exclusion criteria were: (i) systematic reviews, meta-analyses, case reports, or animal studies; (ii) duplicated studies; (iii) incomplete or inconsistent data. Quality assessment was conducted with Newcastle-Ottawa Scale criteria or Cochrane Collaboration. Data of live birth, abortion, birth weight, fetal growth restriction (FGR), and adverse events were extracted and synthesized.

RESULTS

Six eligible studies (4 observational studies and 2 RCTs) with 321 patients receiving fondaparinux and 546 patients receiving LMWH were enrolled. Live birth (relative risks (RR) = 1.05, 95% confidence interval (CI) = 0.97 ∼ 1.14, P = 0.217), abortion (RR = 0.73, 95% CI = 0.50 ∼ 1.08, P = 0.113), birth weight (weighted mean difference = 167.20, 95% CI = -236.89 ∼ 571.30, P = 0.417), and FGR (RR = 0.95, 95% CI = 0.25 ∼ 3.59, P = 0.942) were of no difference between patients receiving fondaparinux and LMWH. Regarding adverse events, the incidence of ecchymosis (RR = 0.11, 95% CI = 0.03 ∼ 0.46, P = 0.002) and skin reaction at injection site (RR = 0.15 95% CI = 0.05 ∼ 0.44, P = 0.001) were lower in patients receiving fondaparinux compared with those receiving LMWH, while that of thrombocytopenia (RR = 0.45, 95% CI = 0.09 ∼ 2.14, P = 0.315), vagina bleeding (RR = 1.03, 95% CI = 0.62 ∼ 1.71, P = 0.646), and oral mucosa hemorrhage (RR = 1.08, 95% CI = 0.33 ∼ 3.51, P = 0.899) did not vary between these patients receiving these two treatments. However, most studies were conducted in China, which could induce regional and ethnic bias.

CONCLUSION

Fondaparinux is attributable to fewer adverse events and similar pregnancy outcomes compared with LMWH in patients with recurrent miscarriage.

Perturbations in kinetics of the thrombin generation assay identify women at risk of preeclampsia in the first trimester and provide the rationale for a preventive approach

BACKGROUND

Activation of the coagulation system and increased thrombin generation have been implicated in the pathophysiology of preeclampsia, and this rationale supports the administration of low-molecular-weight heparin to prevent this syndrome in patients at risk. Yet, randomized trials of this prophylactic measure have yielded contradictory results. A possible explanation is that only a subset of patients with preeclampsia have excessive thrombin generation and would benefit from the administration of low-molecular-weight heparin. Therefore, the key questions are whether and when patients who subsequently develop preeclampsia present evidence of abnormal thrombin generation.

OBJECTIVE

This study aimed to determine (1) the kinetics of thrombin generation throughout gestation in women with a normal pregnancy and in those with early and late preeclampsia, and (2) the diagnostic performance of in vivo thrombin generation parameters to predict the development of preeclampsia.

STUDY DESIGN

This retrospective, nested case-control study was based on a prospective longitudinal cohort of singleton gestations. Cases comprised women who developed preeclampsia (n=49), and controls consisted of patients with a normal pregnancy (n=45). Preeclampsia was classified into early-onset (n=24) and late-onset (n=25). Longitudinal changes in the parameters of the thrombin generation assay (lag time, time to peak thrombin concentration, peak thrombin concentration, endogenous thrombin generation, and velocity index) throughout gestation were compared between the study groups, and normal pregnancy percentiles were derived from the control group. We tested whether a single parameter or a combination of parameters, derived from the kinetics of thrombin generation, could identify patients who subsequently developed preeclampsia. Time-related parameters <10th percentile were considered short, and concentration-related parameters >90th percentile were considered high.

RESULTS

(1) Patients who developed preeclampsia (early- and late-onset) had abnormal thrombin generation kinetics as early as 8 to 16 weeks of pregnancy; (2) patients with a combination of a short lag time and high peak thrombin concentration at 8 to 16 weeks of pregnancy had an odds ratio of 43.87 for the subsequent development of preeclampsia (area under the curve, 0.79; sensitivity, 56.8%; specificity, 92.7%; positive likelihood ratio, 7.76); (3) at 16 to 22 weeks of gestation, patients with a combination of a short lag time and a high velocity index had an odds ratio of 16 for the subsequent development of preeclampsia (area under the curve, 0.78; sensitivity, 62.2%; specificity, 92.5%; positive likelihood ratio, 8.29).

CONCLUSION

During early pregnancy, the thrombin generation assay can identify the subset of patients at a greater risk for the development of preeclampsia owing to accelerated and enhanced production of thrombin. This observation provides a rationale for testing the efficacy of low-molecular-weight heparin in this subset of patients. We propose that future research on the efficacy of low-molecular-weight heparin and other interventions targeting the coagulation system to prevent preeclampsia should be focused on patients with abnormal kinetics of thrombin generation.

Relationship between platelet activation markers and spontaneous abortion: A meta-analysis

Numerous studies have indicated that mean platelet volume (MPV) and platelet distribution width (PDW) were correlated with spontaneous abortion (SAB), but the results were contradictory. Hence, we performed a meta-analysis to assess the association of MPV and PDW with SAB. We systematically searched on China National Knowledge Internet, PubMed, and Embase up to May 2022 to retrieve eligible studies. The synthesized standard mean difference (SMD) with a 95% confidence interval (CI) was used to evaluate the correlation of MPV and PDW with SAB. A total of 20 studies were finally included in this meta-analysis. The pooled analysis results showed that PDW was markedly increased in patients with SAB versus women with a healthy pregnancy (SMD = 1.03; 95% CI: 0.51-1.54; p = 0.0001), while there were no significant differences in MPV between women with SAB and those with healthy pregnancy (SMD = 0.19; 95% CI: -0.26 to 0.65; p = 0.40). Therefore, PDW may serve as a potential marker for predicting SAB. However, homogeneous and multiethnic studies with larger sample sizes are warranted to validate our findings due to several limitations in this meta-analysis.

Hypofibrinogenemia and miscarriage: report of a first successful pregnancy under fibrinogen substitution and short review of the literature

Disorders of fibrinogen have been reported to be associated not only with bleeding and thrombosis but also with miscarriage. Here, we report the case of a woman with genetically determined hypofibrinogenemia and recurrent miscarriages who had a first successful pregnancy under fibrinogen substitution. Current knowledge on fibrinogen disorders and recurrent miscarriages is briefly summarized and discussed.

H1299R Variant in Factor V and Recurrent Pregnancy Loss: A Systematic Review and Meta-Analysis Protocol

Recurrent pregnancy loss (RPL) is defined as the loss of two or more pregnancies, affecting approximately 1 to 3% of women worldwide. Scientific data highlight a possible correlation between thrombophilic genetic variants and RPL. H1299R variant in the factor V gene would lead to an increased thrombotic risk associated with frequent miscarriages. However, the data are often conflicting, making this an interesting question for further investigations by evaluating genotype-phenotype correlations to improve the clinical management and genetic counseling of couples. A systematic review and meta-analysis will follow the preferred reporting elements for systematic review and meta-analysis protocols (PRISMA-P). The Pubmed (MEDLINE) and Embase (OVID) databases will be explored to identify suitable articles based on inclusion and exclusion criteria. Inclusion criteria are: (a) H1299R genotyping with clear data reported, referred to as Heterozygous (Het) and/or Homozygous (Hom); (b) articles written in English; (c) analyses of only RPL female patients having at least two or more previous pregnancy losses and compared with a control group. This analysis will present selected scientific evidence, addressing the questions concerning the association between the H1299R variant and RPL, hoping to clarify this still unresolved issue. PROSPERO registration number: CRD42022330077.