Anticoagulation strategy for patients presenting with ischemic strokes while using a direct oral anticoagulant: A systematic review and meta-analysis.

BACKGROUND: While direct-acting oral anticoagulants (DOACs) have established efficacy in reducing the risk of ischemic stroke, they still leave a residual risk of stroke, which may be greater in practice (0.7-2.3%) than in controlled clinical trial settings. This meta-analysis examines four therapeutic approaches following a stroke in patients already on DOACs: continuing with the same DOAC, changing to a different DOAC, increasing the current DOAC dosage, or switching to a vitamin K antagonist (VKA), such as warfarin. METHODS: Systematic review of literature from the MEDLINE, Embase, and Cochrane databases, was conducted in line with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The analysis focused on six studies with varied patient demographics, examining as outcomes as recurrent ischemic stroke, intracranial hemorrhage, other bleeding events, and mortality. RESULTS: Six studies comprising 12,159 patients were included, all of them were observational. Patients who remained on their initial DOAC regimen had a lower risk of experiencing ischemic strokes (risk ratio (RR) 0.55; 95% confidence interval (CI) 0.43-0.70; p < 0.001; I2 = 0%), intracranial hemorrhage (RR 0.37; 95% CI 0.25-0.55; p < 0.001; I2 = 0%), and hemorrhagic events (RR 0.44; 95% CI 0.30-0.63; p < 0.001; I2 = 6%) compared to those who were switched to warfarin, with an increase in mortality rates (hazard ratio (HR) 1.85; 95% CI 1.06-3.24; p = 0.03; I2 = 84%). In contrast, neither changing to a different DOAC nor adjusting the dose proved to be more effective than the original regimen. CONCLUSION: Post-stroke adjustments to anticoagulation therapy-whether altering the drug or its dosage-do not yield additional benefits. In addition, the results suggest that warfarin may be less effective than DOACs for preventing stroke recurrence, bleeding complications, and death in this patient population.

Andexanet Alfa versus Four-Factor Prothrombin Complex Concentrate for the Reversal of Factor Xa (FXa) Inhibitor-Associated Intracranial Hemorrhage: A Systematic Review of Retrospective Studies.

Background/Objectives: There are limited data on the risks and benefits of using Andexanet alfa (AA) compared with four-factor prothrombin complex concentrate (4F-PCC) for the reversal of factor Xa inhibitor-associated intracranial hemorrhage (ICH). Our aim was to describe a compilation of the information available in the literature to date. Methods: PubMed, Embase, Web of Science (Clarivate Analytics) and the Cochrane Central Register of Controlled Trials were searched until December 2023. Following the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)" guidelines, our systematic literature review included studies that were retrospective in design and evaluated both drugs to control bleeding and complications (death and thromboembolic events). Two researchers re-examined the studies for relevance, extracted the data and assessed the risk of bias. No meta-analyses were performed for the results. Results: In this limited patient sample, we found no differences between published articles in terms of neuroimaging stability or thrombotic events. However, some studies show significant differences in mortality, suggesting that one of the AAs may be superior to 4F-PCC. Conclusions: Our qualitative analysis shows that AA has a better efficacy profile compared with 4F-PCC. However, further studies monitoring these patients and a multicenter collaborative network dedicated to this topic are needed.

Anticoagulantes Orais Diretos versus Antagonistas da Vitamina K para Trombo Ventricular Esquerdo: Uma Metanálise com Análise Sequencial de Ensaios / Direct Oral Anticoagulants versus Vitamin K Antagonists for Left Ventricular Thrombus: A Meta-Analysis with Trial Sequential Analysis

Resumo Fundamento Os antagonistas da vitamina K (AVKs) são o tratamento de primeira linha recomendado para trombo ventricular esquerdo (TVE); entretanto, os anticoagulantes orais diretos (AODs) têm sido considerados uma terapia alternativa. Objetivos Avaliar a eficácia e a segurança dos AODs em comparação com a terapia com AVKs em pacientes com TVE. Métodos PubMed, Embase e Cochrane foram sistematicamente pesquisados em busca de ensaios clínicos randomizados ou estudos de coorte que comparassem AODs versus AVKs para TVE. As razões de risco (RR) foram calculadas para desfechos binários, com intervalos de confiança (IC) de 95%. A significância estatística foi definida como valor de p < 0,05. Resultados Foram incluídos um total de 4 ensaios clínicos randomizados e 29 estudos de coorte, com 4.450 pacientes designados para AODs ou AVKs. Não houve diferença significativa entre os grupos para acidente vascular cerebral ou eventos embólicos sistêmicos (AVC/EES) (RR 0,84; IC 95% 0,65 a 1,07; p = 0,157), acidente vascular cerebral (RR 0,73; IC 95% 0,48 a 1,11; p = 0,140), eventos embólicos sistêmicos (EES) (RR 0,69; IC 95% 0,40 a 1,17; p = 0,166), resolução do trombo (RR 1,05; IC 95% 0,99 a 1,11; p = 0,077), qualquer sangramento (RR 0,78; IC 95% 0,60 a 1,00; p = 0,054), sangramento clinicamente relevante (RR 0,69; IC 95% 0,46 a 1,03; p = 0,066), sangramento menor (RR 0,73; IC 95% 0,43 a 1,23; p = 0,234), sangramento maior (RR 0,87; IC 95% 0,42 a 1,80; p = 0,705) e mortalidade por todas as causas (RR 1,05; IC 95% 0,79 a 1,39; p = 0,752). Em comparação com AVKs, a rivaroxabana reduziu significativamente AVC/EES (RR 0,35; IC 95% 0,16 a 0,91; p = 0,029) e EES (RR 0,39; IC 95% 0,16 a 0,95; p = 0,037). Conclusões Os AODs tiveram uma taxa semelhante de eventos tromboembólicos e hemorrágicos, bem como de resolução do trombo, em comparação com os AVKs no tratamento de TVE. A terapia com rivaroxabana teve uma redução significativa nos eventos tromboembólicos, em comparação com os AVKs.

Abstract Background Vitamin K antagonists (VKAs) are the recommended first-line treatment for left ventricular thrombus (LVT); however, direct oral anticoagulants (DOACs) have been considered an alternative therapy. Objectives To evaluate the efficacy and safety of DOACs compared with VKAs therapy in patients with LVT. Methods PubMed, Embase, and Cochrane were systematically searched for randomized clinical trials or cohort studies that compared DOACs versus VKAs for LVT. Risk ratios (RRs) were computed for binary endpoints, with 95% confidence intervals (95% CIs). Statistical significance was defined as p value < 0.05. Results A total of 4 randomized clinical trials and 29 cohort studies were included, with 4,450 patients assigned to either DOACs or VKAs. There was no significant difference between groups for stroke or systemic embolic (SSE) events (RR 0.84; 95% CI 0.65 to 1.07; p = 0.157), stroke (RR 0.73; 95% CI 0.48 to 1.11; p = 0.140), systemic embolic (SE) events (RR 0.69; 95% CI 0.40 to 1.17; p = 0.166), thrombus resolution (RR 1.05; 95% CI 0.99 to 1.11; p = 0.077), any bleeding (RR 0.78; 95% CI 0.60 to 1.00; p = 0.054), clinically relevant bleeding (RR 0.69; 95% CI 0.46 to 1.03; p = 0.066), minor bleeding (RR 0.73; 95% CI 0.43 to 1.23; p = 0.234), major bleeding (RR 0.87; 95% CI 0.42 to 1.80; p = 0.705), and all-cause mortality (RR 1.05; 95% CI 0.79 to 1.39; p = 0.752). Compared with VKAs, rivaroxaban significantly reduced SSE events (RR 0.35; 95% CI 0.16 to 0.91; p = 0.029) and SE events (RR 0.39; 95% CI 0.16 to 0.95; p = 0.037). Conclusions DOACs had a similar rate of thromboembolic and hemorrhagic events, as well as thrombus resolution, compared to VKAs in the treatment of LVTs. Rivaroxaban therapy had a significant reduction in thromboembolic events, compared to VKAs.

Efficacy and Safety of Direct Oral Anticoagulants for Acute Treatment of Venous Thromboembolism in Older Adults: A Network Meta-Analysis of Randomised Controlled Trials.

OBJECTIVE: This systematic review and network meta-analysis aimed to evaluate the efficacy and safety of direct oral anticoagulants (DOACs) in adults aged 75 and over undergoing acute venous thromboembolism (VTE) treatment. METHODS: PubMed, Embase and the CENTRAL were searched up to 25 December 2023. The incidence of VTE recurrence and bleeding events was assessed. Employing a frequentist network meta-analysis approach, interventions not directly compared could be indirectly assessed through the 95% confidence interval (CI), enhancing the interpretability of the search results. The surface under the cumulative ranking curves (SUCRA) was utilized to generate the relative ranking probabilities for each group. RESULTS: Our study, analysing 6 randomised controlled trials with 3665 patients, compares direct oral anticoagulants (DOACs) and vitamin K antagonists (VKAs) in adults aged 75 and over with acute venous thromboembolism. Edoxaban reduces VTE recurrence risk compared with VKAs (risk ratio [RR] .50, 95% CI 0.27 - .95), while apixaban significantly decreases bleeding risk compared with VKAs (RR .23, 95% CI 0.08 - .69), edoxaban (RR .28, 95% CI 0.09 - .86) and rivaroxaban (RR .28, 95% CI 0.09 - .86). Despite low overall evidence quality, apixaban consistently ranks highest for both efficacy and safety. Findings underscore the nuanced efficacy-safety balance in this population, emphasizing cautious interpretation due to evidence limitations. CONCLUSION: Apixaban emerges as a favourable choice for acute VTE treatment in the elderly, displaying reduced bleeding risk compared to other treatments while maintaining comparable efficacy. Future studies should explore diverse anticoagulants efficacy and safety in older populations. Additionally, clinical prediction models tailored to geriatric cohorts are crucial for guiding treatment duration decisions.

Anticoagulação Crônica em Pacientes com Fibrilação Atrial e COVID-19: Uma Revisão Sistemática e Metanálise / Chronic Anticoagulation in Patients with Atrial Fibrillation and COVID-19: A Systematic Review and Meta-Analysis

Resumo Fundamento: A doença por coronavírus 2019 (COVID-19) está associada à hipercoagulabilidade. Permanece incerto se a anticoagulação contínua para fibrilação atrial (FA) em pacientes que posteriormente contraem COVID-19 melhora os desfechos clínicos. Objetivos: Comparar a anticoagulação oral crônica com ausência de anticoagulação prévia em pacientes com FA que contraíram uma infecção por COVID-19 em relação aos desfechos de mortalidade por todas as causas, mortalidade por COVID-19, admissão em unidade de terapia intensiva (UTI) e hospitalização. Métodos: Buscamos sistematicamente no PubMed, Embase e Cochrane Library estudos elegíveis desde o início até dezembro de 2022. Incluímos estudos que compararam desfechos de COVID-19 em pacientes com e sem anticoagulação crônica prévia para FA. Foram agrupadas razões de risco (RR) com intervalos de confiança (IC) de 95% por meio de um modelo de efeitos aleatórios. O nível de significância foi estabelecido em p < 0,05. As avaliações da qualidade e do risco de viés foram realizadas de acordo com as recomendações da Cochrane. Resultados: Foram identificados 10 estudos abrangendo 1.177.858 pacientes com COVID-19 e FA, dos quais 893.772 (75,9%) estavam em anticoagulação crônica prévia para FA. Em pacientes com COVID-19, a anticoagulação crônica para FA reduziu significativamente a mortalidade por todas as causas (RR 0,75; IC 95% 0,57 a 0,99; p = 0,048; I2 = 89%) e a mortalidade relacionada à COVID-19 (RR 0,76; IC 95% 0,72 a 0,79; p < 0,001; I2 = 0%) quando comparada com a ausência de anticoagulação prévia. Em contrapartida, não houve diferença entre os grupos em relação à hospitalização (RR 1,08; IC 95% 0,82 a 1,41; p = 0,587; I2 = 95%) ou internação em UTI (RR 0,86; IC 95% 0,68 a 1,09; p = 0,216; I2 = 69%). Conclusões: Nesta metanálise, a anticoagulação crônica para pacientes com FA que contraíram COVID-19 foi associada a taxas significativamente mais baixas de mortalidade por todas as causas e mortalidade relacionada à COVID-19 em comparação com a ausência de anticoagulação anterior.

Abstract Background: Coronavirus disease 2019 (COVID-19) is associated with hypercoagulability. It remains uncertain whether ongoing anticoagulation for atrial fibrillation (AF) in patients who later contract COVID-19 improves clinical outcomes. Objectives: To compare chronic oral anticoagulation with no previous anticoagulation in patients with AF who contracted a COVID-19 infection concerning the outcomes of all-cause mortality, COVID-19 mortality, intensive care unit (ICU) admission, and hospitalization. Methods: We systematically searched PubMed, Embase, and Cochrane Library for eligible studies from inception to December 2022. We included studies comparing COVID-19 outcomes in patients with versus without prior chronic anticoagulation for AF. Risk ratios (RR) with 95% confidence intervals (CI) were pooled with a random-effects model. The level of significance was set at p < 0.05. Quality assessment and risk of bias were performed according to Cochrane recommendations. Results: Ten studies comprising 1,177,858 patients with COVID-19 and AF were identified, of whom 893,772 (75.9%) were on prior chronic anticoagulation for AF. In patients with COVID-19, being on chronic anticoagulation for AF significantly reduced all-cause mortality (RR 0.75; 95% CI 0.57 to 0.99; p = 0.048; I2 = 89%) and COVID-19-related mortality (RR 0.76; 95% CI 0.72 to 0.79; p < 0.001; I2 = 0%) when compared with no prior anticoagulation. In contrast, there was no difference between groups regarding hospitalization (RR 1.08; 95% CI 0.82 to 1.41; p = 0.587; I2 = 95%) or ICU admission (RR 0.86; 95% CI 0.68 to 1.09; p = 0.216; I2 = 69%). Conclusions: In this meta-analysis, chronic anticoagulation for patients with AF who contracted COVID-19 was associated with significantly lower rates of all-cause mortality and COVID-19-related mortality as compared with no previous anticoagulation.

Necesidades de superación de médicos generales en el manejo de los anticoagulantes orales / Needs to overcome general practitioners in the management of oral anticoagulants

Introducción: el progresivo avance en la edad media de la población ha propiciado un incremento de la prescripción del tratamiento anticoagulante oral en la práctica clínica. Objetivo: caracterizar la preparación sobre el manejo de pacientes con anticoagulantes orales en médicos generales de los policlínicos universitarios "Capitán Roberto Fleites", "Chiqui Gómez-Lubián" y "Santa Clara". Métodos: se realizó un estudio descriptivo transversal en el período enero-diciembre de 2020, en tres policlínicos universitarios del municipio de Santa Clara, Villa Clara, Cuba. Se utilizaron métodos teóricos: análisis-síntesis e inducción-deducción para la fundamentación de la información; empíricos: cuestionario y análisis de documentos; y matemático estadísticos para el procesamientos de los datos. Resultados: el cuestionario permitió valorar los conocimientos sobre el tratamiento con anticoagulantes orales en la categoría Regular en la mayoría de los muestreados; mientras en el análisis del programa se detectaron pocas horas dedicadas al tema investigado y la necesidad sentida de capacitación manifestada por los encuestados. Conclusiones: el diagnóstico realizado confirmó las carencias de los médicos generales en el manejo del paciente en la prescripción del tratamiento con anticoagulantes orales.

Background: the progressive advance in the average age of the population has led to an increase in the prescription of oral anticoagulant treatment in clinical practice. Objective: to characterize the training on the management of patients with oral anticoagulants in general practitioners of the "Capitán Roberto Fleites", "Chiqui Gómez-Lubian" and "Santa Clara" university polyclinics. Methods: a cross-sectional descriptive study was carried out from January to December 2020. Theoretical methods were used: analysis-synthesis and induction-deduction to support the information; Empirical: questionnaire and analysis of documents and statistical mathematics for data processing. Results: the questionnaire allowed to assess knowledge about treatment with oral anticoagulants in the average category in the majority of those sampled; while in the analysis of the program, few hours dedicated to the subject investigated and the felt need for training expressed by the respondents were detected. Conclusions: the diagnosis made confirmed the shortcomings of general practitioners in the management of medicated patients for the prescription of treatment with oral anticoagulants.

Anticoagulantes Orales de Acción Directa y sus Implicancias en la Exodoncia: Una Revisión Sistemática / Direct Acting Oral Anticoagulants and their Implications in Dental Extraction: A Systematic Review

El uso de Anticoagulantes Orales de Acción Directa (ACOD) ha aumentado considerablemente en el último tiempo. En procedimientos odontológicos, como la exodoncia, es crucial un manejo óptimo de la hemostasia de pacientes bajo tratamiento con ACOD, para equilibrar el riesgo de hemorragia y tromboembolismo. Aun no existe consenso sobre el protocolo a aplicar en pacientes con ACOD sometidos a exodoncias. El objetivo fue evaluar la necesidad de suspender o continuar el tratamiento con ACOD en pacientes sometidos a exodoncia en relación con la incidencia de episodios hemorrágicos y protocolos utilizados. Se realizó una revisión sistemática en base a los estamentos PRISMA, en las bases de datos Pubmed, Wiley, Scopus. La búsqueda incluyó estudios publicados entre 2010 - 2020 en inglés, realizados en humanos, en pacientes bajo terapia con ACOD sometidos a exodoncia y que evalúan la incidencia de hemorragia en este procedimiento. Se excluyeron estudios que involucran pacientes que reciben otros tratamientos antitrombótico concomitante, o procedimientos distintos a la exodoncia. La calidad de los estudios seleccionados fue evaluada de acuerdo con la clasificación del Centro Oxford de Medicina Basada en la Evidencia. Luego de la búsqueda, en base a criterios de inclusión/exclusión, 34 artículos fueron analizados a texto completo. Trece artículos relevantes fueron seleccionados. Once participaron en la revisión final, contando con ocho estudios de cohorte, dos casos-controles y uno serie de casos. Los estudios evidencian que no es necesario suspender la terapia con ACOD en pacientes sometidos a exodoncia, se sugiere que el momento de baja concentración farmacológica puede ser utilizado a favor del tratante. Sin embargo, existe una gran diversidad de protocolos y medidas aplicadas entre estudios, por lo que es necesario realizar estudios clínicos aleatorizados controlados, para determinar un protocolo estándar en el manejo odontológico de estos pacientes.

The use of Direct Acting Oral Anticoagulants (ACOD) has increased considerably in recent times. In dental procedures, such as tooth extraction, optimal management of hemostasis in patients treated with ACOD is crucial to balance the risk of bleeding and thromboembolism. There is still no consensus on the protocol to be applied in patients with ACOD in dental extraction. The aim was to evaluate the need to suspend or continue treatment with ACOD in patients submitted to dental extraction in relation to the incidence of bleeding episodes and the protocols used. A systematic review was carried out based on the PRISMA estates, in the Pubmed, Wiley, Scopus databases. The search included studies published between 2010-2020 in English conducted in humans, in patients under therapy with ACOD submitted to dental extraction and that evaluate the incidence of bleeding in this procedure. Studies involving patients receiving other concomitant antithrombotic treatments or procedures other than dental extraction were excluded. The quality of the selected studies was evaluated according to the Oxford Center for Evidence-based Medicine classification. After the search, based on inclusion/ exclusion criteria, 34 articles were analyzed in full text. 13 relevant articles were selected. 11 participated in the final review, including 8 cohort studies, 2 case-controls and 1 case series. Studies show that it is not necessary to suspend therapy with ACOD in patients who have undergone dental extraction, it is suggested that the moment of low pharmacological concentration can be used in favor of the treatment. However, there is a great diversity of protocols and measures applied between studies, so it is necessary to carry out randomized controlled clinical studies to determine a standard protocol in the dental management of these patients.

Antiphospholipid Syndrome Committee of the Brazilian Society of Rheumatology position statement on the use of direct oral anticoagulants (DOACs) in antiphospholipid syndrome (APS).

BACKGROUND: The term Direct Oral Anticoagulants (DOACs) refers to a group of drugs that inhibit factor Xa or thrombin. Even though their use for treating different thrombotic or prothrombotic conditions is increasing recently, there is no compelling evidence indicating that those medications are safe in all antiphospholipid syndrome (APS) patients. METHODOLOGY: To address this issue, specialists from the Antiphospholipid Syndrome Committee of the Brazilian Society of Rheumatology performed a comprehensive review of the literature regarding DOACs use in APS to answer the three following questions: (1) potential mechanisms of action of these drugs that could be relevant to APS pathogenesis, (2) DOACs interference on lupus anticoagulant testing, and (3) the efficacy of DOACs in APS. POSITION STATEMENT: After critically reviewing the relevant evidence, the authors formulated 8 Position Statements about DOACs use in APS. CONCLUSION: DOACs should not be routinely used in APS patients, especially in those with a high-risk profile (triple positivity to aPL, arterial thrombosis, and recurrent thrombotic events). In addition, DOACs interferes with LA testing, leading to false-positive results in patients investigating APS.

Innovative Three-Step Microwave-Promoted Synthesis of N-Propargyltetrahydroquinoline and 1,2,3-Triazole Derivatives as a Potential Factor Xa (FXa) Inhibitors: Drug Design, Synthesis, and Biological Evaluation.

The coagulation cascade is the process of the conversion of soluble fibrinogen to insoluble fibrin that terminates in production of a clot. Factor Xa (FXa) is a serine protease involved in the blood coagulation cascade. Moreover, FXa plays a vital role in the enzymatic sequence which ends with the thrombus production. Thrombosis is a common causal pathology for three widespread cardiovascular syndromes: acute coronary syndrome (ACS), venous thromboembolism (VTE), and strokes. In this research a series of N-propargyltetrahydroquinoline and 1,2,3-triazole derivatives as a potential factor Xa (FXa) inhibitor were designed, synthesized, and evaluated for their FXa inhibitor activity, cytotoxicity activity and coagulation parameters. Rational design for the desired novel molecules was performed through protein-ligand complexes selection and ligand clustering. The microwave-assisted synthetic strategy of selected compounds was carried out by using Ullmann-Goldberg, N-propargylation, Mannich addition, Friedel-Crafts, and 1,3-dipolar cycloaddition type reactions under microwave irradiation. The microwave methodology proved to be an efficient way to obtain all novel compounds in high yields (73-93%). Furthermore, a thermochemical analysis, optimization and reactivity indexes such as electronic chemical potential (µ), chemical hardness (η), and electrophilicity (ω) were performed to understand the relationship between the structure and the energetic behavior of all the series. Then, in vitro analysis showed that compounds 27, 29-31, and 34 exhibited inhibitory activity against FXa and the corresponding half maximal inhibitory concentration (IC50) values were calculated. Next, a cell viability assay in HEK293 and HepG2 cell lines, and coagulation parameters (anti FXa, Prothrombin time (PT), activated Partial Thromboplastin Time (aPTT)) of the most active novel molecules were performed to determine the corresponding cytotoxicity and possible action on clotting pathways. The obtained results suggest that compounds 27 and 29 inhibited FXa targeting through coagulation factors in the intrinsic and extrinsic pathways. However, compound 34 may target coagulation FXa mainly by the extrinsic and common pathway. Interestingly, the most active compounds in relation to the inhibition activity against FXa and coagulation parameters did not show toxicity at the performed coagulation assay concentrations. Finally, docking studies confirmed the preferential binding mode of N-propargyltetrahydroquinoline and 1,2,3-triazole derivatives inside the active site of FXa.

Nuevos anticoagulantes orales en la prevención de fenómenos tromboembólicos en la fibrilación auricular no valvular / New oral anticoagulants in thromboembolism prevention in nonvalvular atrial fibrillation

La fibrilación auricular es la arritmia cardiaca más frecuente en la práctica clínica. El valor de la anticoagulación con antagonistas de la vitamina K -como la warfarina-en la prevención de los fenómenos embólicos está ampliamente demostrada, pero también su difícil manejo por las conocidas interacciones con otros fármacos e incluso los alimentos. En la búsqueda del anticoagulante ideal, en los últimos años han aparecido nuevos agentes antitrombóticos y otros se encuentran en fases avanzadas de investigación. En la presente revisión, se describe los resultados del desarrollo de los nuevos agentes anticoagulantes y sus expectativas, oportunidades y desafíos, que enfrentarán estos nuevos agentes, los inhibidores directos de la trombina y del factor Xa.

Atrial fibrillation is the most frequent cardiac arrhythmia in clinical practice. The value of anticoagulation with vitamin K antagonists like warfarin in the prevention of embolic phenomena is widely demonstrated but managing is difficult because of its known interactions with other drugs and even food. Looking for the ideal anticoagulant in the last years new antithrombotic agents have appeared and others are in advanced phases of investigation. In the current review results of new anticoagulant agents development and expectations, opportunities and challenges are described in regards to direct thrombin and Xa factor inhibitors.