Hereditary Antithrombin Deficiency Pilot Project Registry from the American Thrombosis and Hemostasis Network (ATHN).

BACKGROUND: Patients with hereditary antithrombin deficiency (HAD) have an increased risk of venous thromboembolism (VTE). ATHN 12: HAD Pilot Project established a registry to collect data on patients with HAD to inform current practice and serve as a platform to design a multicenter global registry for patients with HAD. METHODS: The HAD registry was designed in 2020 to identify 100 patients with HAD receiving care at ATHN-affiliated centers. Demographics, type of HAD, thrombotic events, risk factors, anticoagulants, and AT concentrate administration were recorded. RESULTS: Ninety-four (94) patients were included; 65% were females; 51% had type 1 HAD. Mean age at diagnosis was 26 years (SD18); 61% had VTE: 55% deep vein thrombosis and 27% pulmonary embolisms. Eight patients had arterial thrombosis. Recurrent thrombosis occurred in 58.6% patients: (44.8%) despite anticoagulation. The main risk factor for thrombosis in females was estrogen. Direct oral anticoagulants were prescribed in 30%, heparin in 34%, and warfarin in 32%. There were 139 pregnancies. Low molecular weight heparin was administered in 33% and AT concentrate in 19% and 11% prior and post-delivery, respectively. Twelve patients developed thrombosis in pregnancy. Seventy-nine patients underwent 239 surgeries or procedures, mainly gastrointestinal and vascular, respectively. Overall, 35% participants received AT concentrate without adverse events. CONCLUSIONS: In ATHN 12, VTE was the predominant manifestation, frequently recurrent. There was a trend towards using DOACs. LMWH was administered in one-third of pregnancies and AT concentrate in one-fifth without adverse events. These data should encourage prospective studies to optimize the management of these patients.

Cerebral Vein Thrombosis and Direct Oral Anticoagulants: A Review.

Cerebral venous thrombosis (CVT) is a rare type of cerebrovascular event in which the thrombosis occurs in a vein of the cerebral venous system. The diagnosis could be challenging due to the great clinical variability, but the outcome is favourable in most cases, especially in the case of early diagnosis. Anticoagulant therapy is the core of CVT management and currently consists of heparin in the acute phase followed by vitamin K antagonists (VKAs) in the long term. The ideal duration of anticoagulant therapy is still unclear, and the same criteria for the treatment of extracerebral venous thromboembolism currently apply. In this paper, we reviewed the literature regarding the use of direct oral anticoagulants (DOACs) in CVT since in recent years a considerable number of studies have been published on the use of these drugs in this specific setting. DOACs have already been shown to be equally effective with VKAs in the treatment of venous thromboembolism. In addition to efficacy, DOACs appear to have the same safety profile, being, on the other hand, more manageable, as they do not require close monitoring with continuous personalised dose adjustments. In addition, a further advantage of DOACs over VKAs is the possibility of anticoagulant prophylaxis using a reduced dosage of the drug. In conclusion, although the use of DOACs appears from preliminary studies to be effective and safe in the treatment of CVT, additional studies are needed to include these drugs in the treatment of CVT.

Acquired antithrombin deficiency in adult patients with postcardiotomy extracorporeal membrane oxygenation.

INTRODUCTION: This study aimed to investigate the relationship between acquired antithrombin deficiency in patients undergoing postcardiotomy extracorporeal membrane oxygenation (PC-ECMO) and thromboembolic or haemorrhagic events such as bleeding, peripheral arterial thromboembolism, and ischemic cerebrovascular events. METHODS: The study was designed as a single-center, prospective study and conducted at our hospital between November 2019 and June 2021. 50 patients who underwent ECMO due to postcardiotomy cardiogenic shock were included in the study. Antithrombin (AT) activity testing was performed immediately after ECMO placement and continued for 5 days. The total of haemorrhagic or thromboembolic events was defined as morbidity. The entire patient population was assessed daily for AT measurements according to morbidity status, and ROC analysis was applied to determine the cut-off point. The correlation between clinical outcomes and morbidities with antithrombin levels was analysed. RESULTS: In our study, we identified a cut-off for AT levels on the first postoperative day. The risk of both bleeding (p = .006) and thromboembolism (p = .012) was significantly higher in patients below the 48.9% cut-off value. AT levels were compared with data on separation from PC-ECMO. The rate of separation from ECMO was 7.969 times higher in cases with AT levels above 51.8 on the third postoperative day and 5.6 times higher in cases with AT levels above 47.5 on the fourth postoperative day. CONCLUSION: Acquired antithrombin deficiency may develop in adults undergoing PC-ECMO. In our study, we demonstrated that in patients with low antithrombin levels, the risk of bleeding and thromboembolism increased. Additionally, since AT levels were higher in survivors, this can be considered an indicator of severity. This study is the first prospective study related to determining target antithrombin levels in adult patients undergoing PC-ECMO.

Venous thromboembolism risk in adults with hereditary thrombophilia: a systematic review and meta-analysis.

This systematic review and meta-analysis assesses venous thromboembolism (VTE) risk in adults with hereditary thrombophilia, including Factor V Leiden (FVL) mutation, prothrombin G20210A (FII) mutation, compound heterozygosity, protein C (PC), protein S (PS), and antithrombin (AT) deficiency. Eligibility criteria included studies suitable for quantitative synthesis with extractable information on VTE risk in adults (> 15 years). There were no restrictions on VTE type, location, or occurrence. Two authors reviewed all studies and extracted data from 107 publications, encompassing 107,130 individuals (21,560 experiencing VTE). We used a random effects model and calculated odds ratios (ORs) with 95% confidence intervals (CIs). The highest risk was associated with homozygous FVL (OR 5.58, 95% CI 4.61-6.74), homozygous FII (OR 5.16, 95% CI 3.12-8.52), and compound heterozygosity (OR 4.64, 95% CI 2.25-9.58). In contrast, VTE risk was lowest for FVL heterozygosity (OR 2.97, 95% CI 2.41-3.67) and FII heterozygosity (OR 2.21, 95% CI 1.70-2.87), whereas PC (OR 3.23, 95% CI 2.05-5.08), PS (OR 3.01, 95% CI 2.26-4.02), and AT deficiency (OR 4.01, 95% CI 2.50-6.44) demonstrated an intermediate VTE risk. These results highlight an increased risk of venous thromboembolism in adults with hereditary thrombophilia. However, the risk for patients with PC, PS, and AT deficiency appears to be lower than previously stated, likely due to varying thrombogeneity of the underlying genetic mutations. Further research addressing this aspect of VTE risk in hereditary thrombophilia is imperative to improve patient management. TRIAL REGISTRATION: PROSPERO registration number CRD42022376757.

Post-extraction bleeding in patients on direct oral anticoagulants.

Objectives: This study aimed to evaluate the association between use of direct oral anticoagulants (DOACs) and post-extraction bleeding and to quantify bleeding risk in patients receiving DOACs. Materials and Methods: The study included 293 patients who were taking DOACs and underwent tooth extraction (414 teeth). The patients were divided into those who had the extraction while taking DOACs and those who discontinued DOACs before the extraction. Bleeding complications were recorded and compared between the patient groups and types of DOACs. Results: Of the 293 patients, 12 patients (6.9%) had post-extraction bleeding. Post-extraction bleeding occurred in 12 of the 414 tooth extraction sites. Among the 246 patients who underwent dental extraction while continuing DOAC therapy, 12 patients (8.5%) had post-extraction bleeding. Among the 47 patients who underwent dental extraction after discontinuing the administration of DOACs, none reported post-extraction bleeding. There was no significant difference in the number of patients with post-extraction bleeding between the two groups (P=0.122). Conclusion: Continuing DOAC therapy during dental extraction does not increase post-extraction bleeding tendency. These results are consistent with those of previous studies.

Clinical outcomes of antithrombin III supplementation in an overt disseminated intravascular coagulation: a longitudinal single-institutional experience and retrospective analysis.

BACKGROUND: Antithrombin is a small plasma glycoprotein synthesized in the liver that belongs to the serpin family of serine protease inhibitors and inactivates several enzymes in the coagulation pathway. It plays a leading major factor on coagulation pathway, therefore administration of antithrombin is essential to treat serious clinical conditions such as disseminated intravascular coagulation (DIC). Despite the theoretical benefits of antithrombin supplementation, the optimal antithrombin activity for heparin efficacy and the benefits of antithrombin supplementation in various disease entities are not yet fully understood. METHODS: The strict administration guidelines on antithrombin III in cases of DIC by the National Health Insurance Service and the Ministry of Food and Drug Safety complied as follows: antithrombin levels below 20 mg/dL in adults; antithrombin activity below 70% of normal in adults; total administration period of antithrombin must be carefully limited to within maximum 3 days, and the total administration dose must be below 7,000 international unit (IU), (loading dose, 1,000 IU in 1 hour: maintenance dose, 500 IU every 6 hours for 3 days). RESULTS: We identified 76 eligible for analysis according to the above-mentioned criteria in our institution (male/female, 59/17). Forty-four were identified to the non-survivor group and 32 patients were recognized as the survivor group. The baseline parameters in the non-survivor and survivor groups were comparable with no significant differences in age (66.5±18.1 vs. 66.0±16.2 years, P=0.90), sex (32/12 vs. 27/5, P=0.35), hospital length of stay (31.1±34.5 vs. 31.2±26.1 days, P=0.99), sequential organ failure assessment (SOFA) (7.3±2.5 vs. 6.6±2.0, P=0.22), simplified acute physiology score II (SAPS II) (46.0±8.8 vs. 43.5±9.2, P=0.23), cause for DIC (P=0.95), and underlying disease (P=0.38). The levels of antithrombin III on the day just before the administration significantly lower in the non-survivor groups than in the survivor groups (50.1%±13.6% vs. 57.6%±12.5%, P=0.01). The hemoglobin level in the 2nd day and 7th day after antithrombin III administration was significantly different between the non-survivor and survivor groups (9.9±1.9 vs. 11.0±2.0 g/dL, P=0.01, and 9.4±1.8 vs. 10.5±1.6 g/dL, P=0.006). The antithrombin III levels on the day of administration [area under the curve (AUC) =0.672] demonstrated significantly better prediction of mortality than the A antithrombin III levels on 1st day (AUC =0.552), the 2nd day (AUC =0.624), and 7th day (AUC =0.593). CONCLUSIONS: Our study suggests that the antithrombin administration may be effective tools for DIC treatment, and may be more positively considered, especially in the cases of DIC, which is a frequent complication of septic shock, sepsis, and other critical disease entities and which is associated with a high level of mortality. Furthermore, our study also suggests that the total doses and periods of antithrombin administration, which recommended by national guidelines, may be insufficient, therefore prolongation of period and increase of total dose of antithrombin supplement might be necessary.

Retrieval of a left appendage device from the left ventricle using a large bore steerable catheter.

Left atrium appendage closure is a safe and effective therapy for patients with atrial fibrillation and high thromboembolic and hemorrhagic risks. Prosthesis embolization is a potential major complication with an incidence of 0.07%. We report a case of migration of an Amplatzer Amulet (Abbott) device that was successfully retrieved in an innovative way (4).

Recurrent hypo-attenuated leaflet thickening after TAVR: Clinical implications.

Subclinical bioprosthetic valve thrombosis (BPVT) is a relatively common finding in asymptomatic patients during follow-up imaging. However, its clinical significance is unclear. Data from registries associate BPVT with elevated valve gradients, thromboembolic complications, recurrence, and valve degeneration. Given the dynamic nature of the disease process, management is challenging. The duration of anticoagulation is unpredictable, and the need for frequent monitoring of BPVT, even in subclinical scenarios, is unclear. Our report is shedding the light on the clinical implications BPVT.

First-in-human trial of SAR107375E, a novel small molecule anticoagulant with dual inhibition of factor Xa and factor IIa.

BACKGROUND: SAR107375E is a direct dual inhibitor of both Factor Xa and Factor IIa and has shown potent anticoagulation activity in vitro and animals. This study evaluated the safety, tolerability, pharmacokinetics, and pharmacodynamics of single ascending intravenous doses of SAR107375E in healthy Chinese adult subjects. METHODS: In this randomized, double-blind, placebo-controlled trial, 60 healthy Chinese adult subjects were administered intravenously single ascending doses (0.5, 1.5, 3.0, 5.0, 7.5, 10.0, 15.0, or 20.0 mg) of SAR107375E (N = 44) or placebo (N = 16). Plasma and urine concentrations of SAR107375E were measured and used to calculate pharmacokinetic parameters. Coagulation functions were measured and compared with baseline values. Treatment-emergent adverse events were recorded to evaluate safety. RESULTS: In plasma, from the 0.5 to 20.0 mg dose group, t1/2 is 1.51-4.00 h, Cmax is 59.05-1360 ug/L, and AUC0-t is 25.01-528.45 h*ug/L. And it shows dose proportionality in the 5.0-20.0 mg range. Activated partial thromboplastin time and Ecarin clotting time correlated linearly with drug plasma concentration. No serious adverse events were reported during the study. CONCLUSION: SAR107375E exhibits good safety and tolerability, predictable pharmacokinetics and pharmacodynamics. CLINICAL TRIAL REGISTRATION: www.chinadrugtrials.org.cn, identifier is CTR20211082.

Delayed coronary perforation four days after percutaneous coronary intervention with subsequent cardiac tamponade: A case report.

Coronary artery perforation (CAP) is a rare but lethal complication of percutaneous coronary interventions (PCIs), and its incidence has been increasing with advances in PCI techniques. Delayed CAP presents a highly challenging complication, as it occurs 30 min-9 days after intervention, making subsequent diagnosis and treatment difficult. We present the case of a 63-year-old male patient who underwent PCI for an obtuse marginalis II because of posterior wall myocardial infarction. Following 4 days of uneventful postoperative stay, the patient developed angina pectoris and hypotension 4 h after reinitiation of anticoagulant therapy with edoxaban. Angiography revealed distal vessel perforation from a side branch of the obtuse marginalis II. The vessel was occluded using autologous fat embolization via a microcatheter, resulting in complete sealing of the perforation. After discharge, 4 weeks after the infarction, the patient started rehabilitation therapy. Distal vessel perforations are typically caused by wire damage. In our case, we also suspected distal wire perforation, which was initially not recognized possibly due to distal occlusion through the thrombotic material. The temporal correlation between the re-initiation of anticoagulant therapy and the occurrence of cardiac tamponade suggests that the thrombotic material was resolved due to the former. The management of delayed CAP does not differ from that of CAP; thus, this rare complication should be considered even days after PCI as it could prove lethal if not recognized early.

OKL-1111, A modified cyclodextrin as a potential universal reversal agent for anticoagulants.

BACKGROUND: Antithrombotic therapy is inevitably associated with a risk for bleeding and these bleeding complications can be life-threatening. Recently, specific reversal agents were developed for the direct factor Xa and thrombin inhibitors (DOACs). However, next to the fact that these agents are relatively expensive, the use of selective reversal agents complicates treatment of bleeding patients in practice. In a series of screening experiments, we discovered a class of cyclodextrins with procoagulant properties. In this study we characterize a lead compound, OKL-1111, and demonstrate its potential use as a universal reversal agent. OBJECTIVES: To assess the anticoagulant reversal properties of OKL-1111, in vitro and in vivo. METHODS: The effect of OKL-1111 on coagulation in the absence and presence of DOACs was investigated in a thrombin generation assay. Its reversal effect on a variety of anticoagulants in vivo was investigated in a rat tail cut bleeding model. A possible prothrombotic action of OKL-1111 was assessed in a Wessler model in rabbits. RESULTS: OKL-1111 concentration-dependently reversed the in vitro anticoagulant effects of dabigatran, rivaroxaban, apixaban and edoxaban in the thrombin generation assay. Also in the absence of a DOAC, OKL-1111 concentration-dependently accelerated coagulation in this assay, but did not initiate coagulation. The reversal effect was also seen for all DOACs in the rat tail cut bleeding model. In addition, when tested with other anticoagulants, OKL-1111 also reversed the anticoagulant effect of the vitamin K antagonist warfarin, the low molecular weight heparin enoxaparin, the pentasaccharide fondaparinux and the platelet inhibitor clopidogrel in vivo. OKL-1111 did not have prothrombotic effects in the Wessler model. CONCLUSION: OKL-1111 is a procoagulant cyclodextrin with a currently unknown working mechanism that has potential to become a universal reversal agent for anticoagulants and platelet inhibitors.

Thrombin generation and implications for hemophilia therapies: A narrative review.

Thrombin plays an essential role in achieving and maintaining effective hemostasis and stable clot formation. In people with hemophilia, deficiency of procoagulant factor (F)VIII or FIX results in insufficient thrombin generation, leading to reduced clot stability and various bleeding manifestations. A correlation has been found between the bleeding phenotype of people with hemophilia and the extent of thrombin generation, with individuals with increased thrombin generation being protected from bleeding and those with lower thrombin generation having increased bleeding tendency. The amount, location, and timing of thrombin generation have been found to affect the formation and stability of the resulting clot. The goal of all therapies for hemophilia is to enhance the generation of thrombin with the aim of restoring effective hemostasis and preventing or controlling bleeding; current treatment approaches rely on either replacing or mimicking the missing procoagulant (ie, FVIII or FIX) or rebalancing hemostasis through lowering natural anticoagulants, such as antithrombin. Global coagulation assays, such as the thrombin generation assay, may help guide the overall management of hemostasis by measuring and monitoring the hemostatic potential of patients and, thus, assessing the efficacy of treatment in people with hemophilia. Nevertheless, standardization of the thrombin generation assay is needed before it can be adopted in routine clinical practice.

Oral Anticoagulant Use and Appropriateness in Elderly Patients with Atrial Fibrillation in Complex Clinical Conditions: ACONVENIENCE Study.

Non-valvular atrial fibrillation (NVAF) is the most common arrhythmia in older patients. Although direct-acting oral anticoagulants (DOAC) are the antithrombotic treatment of choice, irrespective of age, certain factors may limit their use. The aim of the ACONVENIENCE study was to consult the opinion of a multidisciplinary panel of experts on the appropriateness of using OACs in elderly patients (>75 years) with NVAF associated with certain complex clinical conditions. A consensus project was performed on the basis of a systematic review of the literature, and application of a two-round Delphi survey. The agreement of 79 panellists on 30 Delphi-type statements was evaluated, and their opinion on the appropriateness of different oral anticoagulants in 16 complex clinical scenarios was assessed. A total of 27 consensus statements were agreed upon, including all statements addressing anticoagulation in older patients and in patients at high risk of bleeding complications, and most of those addressing frailty, dementia, risk of falling, and complex cardiac situations. It was almost unanimously agreed upon that advanced age should not influence the anticoagulation decision. Apixaban was the highest-rated therapeutic option in 14/16 situations, followed by edoxaban. There is a high degree of agreement on anticoagulation in older patients with NVAF. Age should not be the single limiting factor when prescribing OACs, and the decision should be made based on net clinical benefit and a comprehensive geriatric assessment. Apixaban, followed by edoxaban, was considered the most appropriate treatment in the various complex clinical situations examined.

[Dabigatran Reversal: A Practical Approach]. / Reversão do Dabigatrano: Abordagem Prática.

Dabigatran is a direct oral anticoagulant used to prevent stroke and systemic embolism in patients with atrial fibrillation. In situations that require the urgent reversal of its anticoagulant activity, such as in the case of severe bleeding that is life-threatening; urgent/ emergent surgery or invasive procedures with significant bleeding risk; and the need for thrombolysis in a patient with ischemic stroke, several measures can be taken, including the use of its specific reversal agent, idarucizumab. Based on the guidelines for the use of reversal agents for oral anticoagulants, and on the clinical experience of reversal of dabigatran, a practical guide is presented for use in clinical situations where reversal of dabigatran anticoagulation is required, including the use of idarucizumab. The adoption of this type of guideline contributes to therapeutic optimization and, consequently, greater reversal efficiency and a better resource management.

O dabigatrano é um anticoagulante oral direto utilizado na prevenção do acidente vascular cerebral (AVC) e embolia sistémica em doentes com fibrilhação auricular. Em situações que implicam a reversão urgente da sua atividade anticoagulante, como em caso de hemorragia grave com risco de vida; cirurgia ou manobra invasiva urgente/ emergente com risco hemorrágico significativo; e necessidade de trombólise em doente com AVC isquémico, podem ser adotadas diversas medidas, nomeadamente o recurso ao seu agente de reversão específico, o idarucizumab. Com base nas orientações de utilização dos agentes de reversão dos anticoagulantes orais e na experiência clínica de reversão do dabigatrano, apresenta-se um guia prático de atuação em situações urgentes de necessidade de reversão da anticoagulação do dabigatrano, incluindo a utilização de idarucizumab. A adoção deste tipo de protocolos contribui para a otimização terapêutica e, consequentemente, uma reversão mais eficaz e uma melhor gestão dos recursos.

Benefit Profile of Thrombomodulin Alfa Combined with Antithrombin Concentrate in Patients with Sepsis-Induced Disseminated Intravascular Coagulation.

Thrombomodulin alfa (TM-α, recombinant human soluble thrombomodulin) and antithrombin (AT) concentrate are anticoagulant agents for the treatment of disseminated intravascular coagulation (DIC). A post hoc analysis using data from 1198 patients with infection-induced DIC from the post-marketing surveillance of TM-α was conducted. To identify subgroups that benefit from combination therapy, the patients were a priori stratified into four groups by a platelet (Plt) count of 50 × 103/µL and plasma AT level of 50% (groups 1, 2, 3, and 4, with high Plt/high AT, high Plt/low AT, low Plt/high AT, and low Plt/low AT, respectively). Kaplan-Meier survival analysis showed significantly worse survival in groups 2 and 4 had than in group 1 (p = 0.0480, p < 0.0001, respectively), and multivariate analysis showed that concomitant AT concentrate was independently correlated with reduced 28-day mortality only in group 4 (hazard ratio 0.6193; 95% confidence interval, 0.3912-0.9805). The adverse drug reactions (ADRs) and bleeding ADRs were not different among the groups. Patients with both severe thrombocytopenia and AT deficiency are candidates for combined anticoagulant therapy with TM-α and AT concentrate.