New oral anticoagulants: their advantages and disadvantages compared with vitamin K antagonists in the prevention and treatment of patients with thromboembolic events

Evaluation of the safety and efficacy of direct oral anticoagulants compared with vitamin-k antagonists in the treatment of left ventricular thrombosis. A systematic review and meta-analysis

BACKGROUND

Since the introduction of direct oral anticoagulants (DOACs) and their comparison with vitamin K antagonists (VKAs), conflicting results have been reported regarding the optimal treatment for left ventricular thrombosis (LVT).

OBJECTIVES

In this meta-analysis, we intend to comprehensively evaluate the safety and efficacy of these treatments.

METHODS

All clinical trials and cohorts that compared the efficacy or safety of VKAs with DOACs in the treatment of LVTs were systematically searched until April 15, 2023.

RESULTS

The results of 32 studies with a pooled sample size of 4213 patients were extracted for meta-analysis. DOACs, especially rivaroxaban and apixaban, cause faster resolution, lower mortality, and fewer complications (SSE and bleeding events) than VKAs in the management of LVTs.

CONCLUSION

Compared with VKAs, DOACs result in significantly faster (only rivaroxaban) and safer resolution of left ventricular thrombosis.

A comprehensive insight from molecular docking and dynamics with clinical investigation on the impact of direct oral anticoagulants on atheroprotective protein in atrial fibrillation

BACKGROUND

Direct oral anticoagulants (DOACs) have high potency against their therapeutic target and are widely used in the treatment of atrial fibrillation (AF). Most DOACs are often claimed to have adverse effects due to off-target inhibition of essential proteins. Human serum paraoxonase 1 (PON1), one of the essential proteins, known for its anti-inflammatory and antioxidant properties, could be affected by DOACs. Thus, a comparative evaluation of DOACs and their effect on PON1 protein will aid in recommending the most effective DOACs for AF treatment. This study aimed to assess the impact of DOACs on PON1 through a combination of computational and experimental analyses.

METHODS

We focus on apixaban, dabigatran, and rivaroxaban, the most recommended DOACs in AF treatment, for their impact on PON1 through molecular docking and molecular dynamics (MD) simulation to elucidate the binding affinity and drug-protein structural stability. This investigation revealed the most influential DOACs on the PON1 protein. Then experimental validation was performed in DOAC-treated AF participants (n = 42; 19 treated with dabigatran and 23 treated with rivaroxaban) compared to a healthy control group (n = 22) through gene expression analysis in peripheral blood mononuclear cells (PBMC) and serum enzyme concentration.

RESULTS

Our computational investigation showed rivaroxaban (-4.24 kcal/mol) exhibited a lower affinity against the PON1 protein compared to apixaban (-5.97 kcal/mol) and dabigatran (-9.03 kcal/mol) through molecular docking. Dabigatran holds complex interactions with PON1 at GLU53, TYR197, SER193, and ASP269 by forming hydrogen bonds. Additionally, MD simulation revealed that dabigatran disrupts PON1 stability, which may contribute functional changes. Further experimental validation revealed a significant down-regulation (p < 0.05) of PON1 gene expression in PBMC and decreased serum PON1 enzyme concentration on DOAC treatment. Rivaroxaban as about 48% has inhibitory percentage and dabigatran as about 75% of inhibitory percentage compared to healthy control.

CONCLUSION

Overall, our computational and experimental results clearly show the higher inhibitory effect of dabigatran than rivaroxaban. Hence, rivaroxaban will be a better drug candidate for improving the outcome of AF.

Effectiveness and safety in non-valvular atrial fibrillation patients switching from warfarin to direct oral anticoagulants in US healthcare claims

INTRODUCTION

There is a paucity of real-world studies examining the risks of stroke/systemic embolism (SE) and major bleeding (MB) among non-valvular atrial fibrillation (NVAF) patients switching from warfarin to a direct oral anticoagulant (DOAC). This retrospective study was conducted to compare the stroke/SE and MB risks between patients switched from warfarin to apixaban, dabigatran, or rivaroxaban in real-world clinical practice.

MATERIALS AND METHODS

This study used data from four United States commercial claims databases from January 1, 2012 to June 30, 2019. The study population included NVAF patients initially treated with warfarin and switched to apixaban, dabigatran, or rivaroxaban within 90 days of their warfarin prescription ending. Patients were matched 1:1 between the DOACs in each database using propensity scores and then pooled for the final analysis. Cox proportional hazards models were used to calculate the risk of stroke/SE and MB.

RESULTS AND CONCLUSIONS

The final population consisted of 2,611 apixaban-dabigatran, 12,165 apixaban-rivaroxaban, and 2,672 dabigatran-rivaroxaban pairs. Apixaban vs. dabigatran was associated with a lower risk of stroke/SE (hazard ratio [HR]: 0.61; 95% confidence interval [CI]: 0.39-0.96) and MB (HR: 0.67; 95% CI: 0.50-0.91). Apixaban vs. rivaroxaban was associated with a similar risk of stroke/SE (HR: 0.88; 95% CI: 0.73-1.07) and a lower risk of MB (HR: 0.60; 95% CI: 0.52-0.68). There was no significant difference in either risk between dabigatran and rivaroxaban. These results provide important insights into how the risks of stroke/SE and MB for NVAF patients vary when switching from warfarin to different DOACs.

The role of the methoxy group in approved drugs

The methoxy substituent is prevalent in natural products and, consequently, is present in many natural product-derived drugs. It has also been installed in modern drug molecules with no remnant of natural product features because medicinal chemists have been taking advantage of the benefits that this small functional group can bestow on ligand-target binding, physicochemical properties, and ADME parameters. Herein, over 230 methoxy-containing small-molecule drugs, as well as several fluoromethoxy-containing drugs, are presented from the vantage point of the methoxy group. Biochemical mechanisms of action, medicinal chemistry SAR studies, and numerous X-ray cocrystal structures are analyzed to identify the precise role of the methoxy group for many of the drugs and drug classes. Although the methoxy substituent can be considered as the hybridization of a hydroxy and a methyl group, the combination of these functionalities often results in unique effects that can amount to more than the sum of the individual parts.

Study of Use of Dabigatran in Cerebral Venous Sinus Thrombosis

Cerebral venous sinus thrombosis (CVST) is a challenging condition to diagnose and treat due to its diverse range of clinical presentations. The incidence of CVST is increasing, and although diagnostic techniques have improved, the mainstay of treatment is heparin followed by vitamin K antagonist (VKA), warfarin has remained largely unchanged for the past three decades. However, new direct oral anticoagulants (NOACs) like dabigatran have been developed to address the limitations of VKA therapy. Magnetic resonance imaging (MRI) with magnetic resonance venography (MRV) is the current preferred diagnostic method for CVST due to its exceptional sensitivity and specificity. This prospective observational study was set out to investigate the efficacy and safety of dabigatran in treating cerebral venous sinus thrombosis. The study included 30 patients who reported regular intake of 150 mg dabigatran etexilate twice a day. Among the participants, headache was the most commonly reported symptom. The study found that patients treated with dabigatran experienced favorable outcomes, with all patients achieving re-canalization and reporting no major complications. These promising results suggest that dabigatran could be an effective treatment option for CVST cases. However, the study emphasizes the need for larger, multi-center studies to further validate these findings and improve the overall understanding of the condition and its treatment options.

Efficacy and safety of Apixaban in the treatment of cerebral venous sinus thrombosis: a multi-center study

Background

Information regarding the safety and efficacy of specific direct oral anticoagulants (DOAC) in the treatment of cerebral sinus and venous thrombosis (CSVT) is scarce. Apixaban is one of the most frequently prescribed DOACs. Therefore, we aimed to compare the safety and efficacy of Apixaban with those of vitamin k antagonists (VKA) in patients with CSVT.

Methods

Prospective CSVT databases from seven academic medical centers were retrospectively analyzed. Patients treated with Apixaban were compared to those treated with VKA. Data on demographics, clinical presentations, risk factors, radiological and outcome parameters were studied.

Results

Overall, 403 patients were included in the analysis. Of them, 48 (12%) were treated with Apixaban, and 355 (88%) were treated with VKA. Rates of coagulopathies were significantly higher in the VKA-treated patients but no other differences between the groups were found in baseline characteristics and underlying etiology. No significant differences were found between groups in efficacy or safety parameters including the rates of recanalization, favorable outcomes, one-year mortality, seizures, intracranial hemorrhage or CSVT recurrences.

Conclusion

Our data suggests that Apixaban may be safe and effective for patients with CSVT. These results should be tested in prospective randomized clinical studies.

Trends in oral anticoagulant use - A 10-year retrospective analysis from a general medicine department of a tertiary care hospital in south India

BACKGROUND

The prescribing practice of newer oral anticoagulants (NOACs) has not been adequately studied in the Indian scenario.

AIMS

We aimed to describe the prescribing practices of oral anticoagulants, the patient profile and medical comorbidities among patients admitted in a general medicine unit.

METHODS

In this retrospective study of the 2742 patients prescribed vitamin- K antagonists (VKAs), during the study period, 150 cases were randomly taken for analysis to match the 105 NOACs cases. Their demographic details, clinical characteristics and treatment details were analyzed.

RESULTS

More than 95% of anticoagulants prescribed were VKAs. The prescription of anticoagulants was more common in men (median age 63 years) for prescription of NOACs and 52 years for VKAs. Dabigatran (60.9%) and warfarin (81.3%) were the most prescribed drugs in their respective classes. The most common indication was for cardiovascular diseases with atrial fibrillation (32%). Diabetes and hypertension were the most common comorbidities in patients prescribed oral anticoagulants with a larger proportion of patients with heart failure being prescribed VKAs ( P < 0.01). Patients in the NOACs group had a higher HAS-BLED high-risk score (33.3% vs. 17.3%; P = 0.002). Logistic regression analysis revealed that patients with co-morbidities of congestive heart failure were more likely to be prescribed VKAs while diabetics were more likely to receive NOACs.

CONCLUSIONS

VKAs were the most prescribed anticoagulants; congestive heart failure, diabetes, and hypertension were the commonest comorbidities; and atrial fibrillation was the commonest indication. Patients with a high HAS-BLED score were prescribed NOACs more often.

New Triazole-Based Potent Inhibitors of Human Factor XIIa as Anticoagulants

Factor XIIa (FXIIa) functions as a plasma serine protease within the contact activation pathway. Various animal models have indicated a substantial role for FXIIa in thromboembolic diseases. Interestingly, individuals and animals with FXII deficiency seem to maintain normal hemostasis. Consequently, inhibiting FXIIa could potentially offer a viable therapeutic approach for achieving effective and safer anticoagulation without the bleeding risks associated with the existing anticoagulants. Despite the potential, only a limited number of small molecule inhibitors targeting human FXIIa have been documented. Thus, we combined a small library of 32 triazole and triazole-like molecules to be evaluated for FXIIa inhibition by using a chromogenic substrate hydrolysis assay under physiological conditions. Initial screening at 200 μM involved 18 small molecules, revealing that 4 molecules inhibited FXIIa more than 20%. In addition to being the most potent inhibitor identified in the first round, inhibitor 8 also exhibited a substantial margin of selectivity against related serine proteases, including factors XIa, Xa, and IXa. However, the molecule also inhibited thrombin with a similar potency. It also prolonged the clotting time of human plasma, as was determined in the activated partial thromboplastin time and prothrombin time assays. Subsequent structure-activity relationship studies led to the identification of several inhibitors with submicromolar activity, among which inhibitor 22 appears to demonstrate significant selectivity not only over factors IXa, Xa, and XIa, but also over thrombin. In summary, this study introduces novel triazole-based small molecules, specifically compounds 8 and 22, identified as potent and selective inhibitors of human FXIIa. The aim is to advance these inhibitors for further development as anticoagulants to provide a more effective and safer approach to preventing and/or treating thromboembolic diseases.

Annulated Heterocyclic[g]Coumarin Composites: Synthetic Approaches and Bioactive Profiling

Coumarins, widely abundant natural heterocyclic compounds, are extensively employed in creating various biologically and pharmacologically potent substances. The hybridization of heterocycles presents a key opportunity to craft innovative multicyclic compounds with enhanced biological activity. Fusing different heterocyclic rings with the coumarin structure presents an intriguing method for crafting fresh hybrid compounds possessing remarkable biological effects. In the pursuit of creating heterocyclic-fused coumarins, a wide range of annulated heterocyclic[g]coumarin composites has been introduced, displaying impressive biological potency. The influence of the linear attachment of heterocyclic rings to the coumarin structure on the biological performance of the resulting compounds has been investigated. This review centers on the synthetic methodologies, structural activity relationship investigation, and biological potentials of annulated heterocyclic[g]coumarin composites. We conducted searches across several databases, including Web of Science, Google Scholar, PubMed, and Scopus. After sieving, we ultimately identified and included 71 pertinent studies published between 2000 and the middle of 2023. This will provide valuable perspectives for medicinal chemists in the prospective design and synthesis of lead compounds with significant therapeutic effects, centered around heterocycle-fused coumarin frameworks.

Factor Xa inhibitors versus warfarin in patients with non-valvular atrial fibrillation and diabetes mellitus: a systematic review and meta-analysis of randomized controlled trials

Background

Patients with non-valvular atrial fibrillation with diabetes face increased stroke and cardiovascular risks. This study compares factor Xa inhibitors and warfarin using data from randomized controlled trials (RCTs).

Methods

MEDLINE, Embase, and Cochrane CENTRAL databases were searched for RCTs comparing the risk of efficacy and safety of any factor Xa inhibitors with dose-adjusted warfarin by diabetes status. Incidence of stroke/systemic embolism, major bleeding, intracranial hemorrhage, ischemic stroke, all-cause mortality, risk of hemorrhagic stroke, and myocardial infarction were among the outcomes of interest. A generic inverse-weighted random-effects model was used to calculate hazard ratios (HRs) with 95 percent confidence intervals (CIs).

Results

After applying exclusion criteria, four RCTs containing 19 818 patients were included in the analysis. Compared with warfarin, meta-analysis showed statistically significant reduction in incidence of stroke/systemic embolism (HR 0.80 [95% CI 0.69-0.92]; P=0.002), intracranial hemorrhage (HR 0.49 [95% CI 0.37-0.65]; P<0.001), and risk of hemorrhagic stroke (HR 0.37 [95% CI 0.20-0.66]; P=0.001) in patients on factor Xa inhibitors. However, there was no discernible difference between two treatment arms in incidence of major bleeding (HR 0.93 [95% CI 0.84-1.04]; P=0.19), ischemic stroke (risk ratio (RR) 0.90 [95% CI 0.73-1.12; P=0.34), myocardial infarction (RR 0.88 [95% CI 0.67-1.15]; P=0.35), and all-cause mortality (RR 0.89 [95% CI 0.79-1.01]; P=0.06).

Conclusion

Factor Xa inhibitors show a favorable balance between efficacy and safety compared with warfarin, which is consistent across a wide range of patients with atrial fibrillation known to be at high risk for both ischemic and bleeding events.

Direct oral anticoagulants compared to warfarin in long-term management of cerebral venous thrombosis: A comprehensive meta-analysis

Objectives

We compared the safety and efficacy of direct oral anticoagulants (DOACs) with those of warfarin in the long-term (≥6 months) treatment of cerebral venous thrombosis (CVT).

Methods

We searched electronic databases up to November 2023 to compare the use of DOACs and warfarin in CVT management. Modified Rankin scores (mRS), new intracranial hemorrhage, all-cause mortality, recurrence and nonrecanalisation events were used to assess outcome. RevMan v5.4 software and the Cochran-Mantel-Haenszel method were utilized to analyse data.

Results

A total of 25 studies involving 2301 patients were identified as having treated CVT with either DOACs or warfarin. Good long-term mRS scores 0-2 (risk ratio [RR] = 1.01, 95% CI = 0.98-1.03; p = 0.61), new intracranial hemorrhage (RR = 1.00, 95% CI = 0.48-2.08; p = 0.99), all-cause mortality (RR = 1.00, 95% CI = 0.50-1.98; p = 0.99), nonrecanalisation (RR = 0.95, 95% CI = 0.77-1.18; p = 0.65) and recurrence venous thrombosis events (RR = 0.63, 95% CI = 0.33-1.22; p = 0.17) were similar between the two treatment arms. Subgroup analysis found recurrence of venous thrombosis was lower in the rivaroxaban group compared to warfarin (2.2% vs. 8.5%, RR = 0.33, 95% CI = 0.11-0.98; p = 0.05).

Conclusion

DOACs and warfarin provide comparable long-term safety and efficacy profiles. DOACs may be preferred over warfarin due to their ease of clinical management.

Safety outcomes of direct oral anticoagulants in older adults with atrial fibrillation: a systematic review and meta-analysis of (subgroup analyses from) randomized controlled trials

Balancing stroke prevention and risk of bleeding in patients with atrial fibrillation (AF) is challenging. Direct oral anticoagulants (DOACs) are by now considered standard of care for treating patients with AF in international guidelines. Our objective was to assess the safety of long-term intake of DOACs in older adults with AF. We included RCTs in elderly (≥ 65 years) patients with AF. A systematic search in MEDLINE and EMBASE was performed on 19 April 2022. For determination of risk of bias, the RoB 2 tool was applied. We pooled outcomes using random-effects meta-analyses. The quality of evidence was assessed using GRADE. Eleven RCTs with a total of 63,374 patients were identified. Two RCTs compared apixaban with either warfarin or aspirin, four edoxaban with either placebo, aspirin, or vitamin K antagonists (VKAs), two dabigatran with warfarin and three rivaroxaban with warfarin. DOACs probably reduce mortality in elderly patients with AF (HR 0.89 95%CI 0.77 to 1.02). Low-dose DOACs likely reduce bleeding compared to VKAs (HR ranged from 0.47 to 1.01). For high-dose DOACS the risk of bleeding varied widely (HR ranged from 0.80 to 1.40). We found that low-dose DOACs probably decrease mortality in AF patients. Moreover, apixaban and probably edoxaban are associated with fewer major or clinically relevant bleeding (MCRB) events compared to VKAs. For dabigatran and rivaroxaban, the risk of MCRB varies depending on dose. Moreover, subgroup analyses indicate that in the very old (≥ 85) the risk for MCRB events might be increased when using DOACs.Registration: PROSPERO: CRD42020187876.

Anticoagulant therapy in orthopedic surgery - a review on anticoagulant agents, risk factors, monitoring, and current challenges

Orthopedic surgeries are associated with high-risk of thromboembolism which occurs in 40% to 60% of orthopedic patients in the absence of thromboprophylaxis. Conventionally heparin anticoagulants were used for thromboprophylaxis and currently direct oral anticoagulants (DOACs) are widely used due to their minimal complexity. Anticoagulant use carries bleeding risk and requires optimal laboratory monitoring through conventional thrombin-based assays, anti-Xa assay, anti-IIa assay and contemporary ecarin chromogenic assay (ECA) and rotational thromboelastometry. Monitoring requires multiple hospital visits and hence, the development of point-of-care assays is gaining momentum. Also, a thorough risk assessment model (RAM) is necessary for successful anticoagulant therapy since it enables personalized approach for better thromboprophylaxis outcomes. Despite welcoming changes, lack of guideline consensus, population-based thromboprophylaxis, deficiencies in risk stratification and non-adherence are still a concern. Stronger clinical and process support system with uniform guidelines approaches and patient-specific RAM can aid in the successful implementation of anticoagulant therapy.

Long duration of atrial high-rate episode is more favorable in predicting ischemic stroke than high CHA2 DS2 -VASc score

OBJECTIVE

This study aimed to explore the roles of duration and burden of atrial high-rate episode (AHRE) on ischemic stroke in patients with pacemaker implantation.

METHODS

Patients with pacemaker implantation for bradycardia from 2013 to 2017 were consecutively enrolled. Data such as gender, age, combined diseases, type of AF, left atrial size, left ventricular size, left ventricular ejection fraction, CHA2 DS2 -VASc score, and anticoagulants were collected. The burden and duration of AHRE based on different interval partition were also recorded in detail to evaluate the impacts on ischemic stroke. Cox regression analysis with time-dependent covariates was conducted.

RESULTS

A total of 220 patients with AHRE were enrolled. The average follow-up time was 48.42 ± 17.20 months. Univariate regression analysis showed that diabetes (p = .024), high CHA2 DS2 -VASc score (≥ 2) (p = .021), long mean AHRE burden (p = .011), long maximal AHRE burden (p = .015), long AHRE duration lasting≥48 h (p = .001) or 24 h (p = .001) or 12 h (p = .005) were prone to ischemic stroke. Further multivariate regression analysis showed that long duration of AHRE (≥48 h) (HR 10.77; 95% CI 3.22-55.12; p = .030) were significantly correlated with stroke in patients with paroxysmal AF. There was no significant correlation between the type of AF and stroke (p = .927).

CONCLUSION

The longer duration of AHRE (≥48 h) was more favorable in predicting ischemic stroke than high CHA2 DS2 -VASc score (≥2).

Non-VKA Oral Anticoagulants in Adult Congenital Heart Disease: a Single-Center Study

PURPOSE

Non-VKA oral anticoagulants (NOACs) prescription is increasing in adults with congenital heart disease (ACHD). However, data on efficacy and safety in ACHD is unclear, particularly in severe CHD. The study aimed to review the safety and efficacy of NOACs in ACHD.

METHODS

Retrospective evaluation of ACHD patients started on NOACs from 2014 to 2020, with the primary endpoints of bleeding or thromboembolic events (TE). CHA2DS2-VASc and HAS-BLED scores were calculated, mortality was assessed, and risk factors for bleeding were identified.

RESULTS

A total of 93 patients were included, the mean age was 52 ± 15 years, 58% were female, 55.9% had moderate CHD, and 23.7% had severe CHD (3.2% Fontan). Most (66%) had a CHA2DS2-VASc score ≥ 2 and 82% HAS-BLED ≤ 2. In a median follow-up of 41 (IQR 21) months (400.4 patient-years), there were TE in two patients. The annual risk for TE was 0.49%/patient/year. The cardiovascular mortality was 2% and all-cause mortality 5%; there were no fatal TE or bleeding events. Minor (n = 6, 6.5%) and major (n = 3, 3.2%) bleeding events were observed, a median of 12 (IQR 15) months after starting NOAC therapy. The annual risk for bleeding was 2.2%/patient/year. Renal disease (HR 14.6 [95% CI 1.23-73.6], p = 0.033) and the HAS-BLED score were predictors of major (adjusted HR 6.97 [95% CI 1.69-28.78], p = 0.007) and minor (adjusted HR 3.80 [95% CI 1.48-9.78], p = 0.006) bleeding complications.

CONCLUSION

In this real-life cohort of selected ACHD, the use of NOACs was safe and effective, with a low incidence of bleeding events.

Usefullness of Heparin Calibrated Anti-Xa Activity to Assess Anticoagulant Activity of Apixaban and Rivaroxaban in Emergency Patients Scheduled for Acute Interventions

(1) Background: Direct oral anticoagulants (DOACs) require monitoring in some critical clinical situations. The specific tests for DOAC monitoring are not yet available in all labs. The aim of this study was to evaluate if a unique, more widespread heparin-calibrated anti-Xa assay could be suitable to estimate the concentrations of apixaban and rivaroxaban in order to establish an algorithm helping our clinicians in their therapeutic decision for patients treated with DOACs in emergencies. (2) Methods: A first retrospective part allowed us to determine of a conversion factor between the measured DOAC concentration and the deducted anti-Xa heparin activity based on optic density. During the second prospective part, both DOAC concentration (ng/mL) and anti-Xa activity heparin (UI/mL) were measured on the same sample, and the previously determined conversion factor was applied to each UI/mL value. We then compared the calculated and measured DOAC concentration values. (3) Results: The analysis of the derivation cohort confirmed a good correlation, especially between the anti-Xa heparin activity and the apixaban concentrations (r = 0.97). Additionally, we determined heparin-calibrated anti-Xa assay cut-offs for invasive procedures at 0.3 UI/mL and for intravenous thrombolysis at 0.51 UI/mL using ROC curves with a sensitivity at 98% and specificity at 95% for 0.3 UI/mL and a sensitivity at 97.7% and specificity at 88.2% for the cut-off of 0.51 UI/mL. In the validation cohort, we confirmed the agreement between measured and calculated DOAC concentrations for the low values, especially around cut-offs with an excellent negative predictive value for 0.51 UI/mL (94% for apixaban and 100% for rivaroxaban) and a good negative predictive value for 0.3 UI/mL (83.3% for apixaban and 85.7% for rivaroxaban). (4) Conclusions: Our results confirm that it is possible to correctly predict or exclude the presence of apixaban/rivaroxaban in emergency situations when specific tests are not readily available.

Factors influencing real-life use of direct oral anticoagulants in patients with cerebral sinus and venous thrombosis

BACKGROUND

Direct oral anticoagulants (DOAC) are advocated as equally effective to vitamin K antagonists (VKA) for the treatment of patients with cerebral sinus and venous thrombosis (CSVT). However, data concerning the real-life management practices in CSVT patients are is lacking.

METHODS

Prospective CSVT databases from four large academic medical centers were retrospectively studied. Demographics, clinical presentations, risk factors, radiological and outcome parameters were compared between CSVT patients treated with DOAC and VKA.

RESULTS

Out of 504 CSVT patients, 43 (8.5%) were treated with DOAC, and the remaining 461 (91.5%) were treated with VKA. All patients with antiphospholipid syndrome (APLA) were treated with VKA (61 vs. 0, p=0.013). Patients with a history or presence of malignancy were also more often treated with VKA (16% vs. 5%, p=0.046). Other risk factors for thrombosis did not differ between the groups. There were no differences in clot extent or location and no differences in the percentage of favorable outcomes or mortality were observed.

CONCLUSION

Our data suggests that only malignancy and antiphospholipid antibodies significantly influenced physician's decisions towards choosing VKA rather than DOAC. DOAC appear to be as effective and safe as VKA in patients with CSVT.

Trial sequential analysis of efficacy and safety of direct oral anticoagulants and vitamin K antagonists against left ventricular thrombus

Meta-analysis may increase the risk of random errors. Trial sequential analysis (TSA) has been developed to adjust for these random errors. We conducted TSA on the efficacy and safety of direct oral anticoagulants (DOACs) and vitamin K antagonists (VKAs) in left ventricular thrombus (LVT) patients in order to estimate how many additional patients should be required to draw definite conclusions. PubMed, Scopus, and Cochrane Library databases were searched for articles directly comparing DOACs and VKAs for LVT in LV thrombus resolution, stroke, any thromboembolism, major bleeding, any bleeding, and all-cause death. TSA was conducted with a cumulative Z-curve, monitoring boundaries, and required sample size. A simulated trial was run and TSA estimated the sample sizes of trials needed to draw definite conclusions. Of 4749 articles, 25 studies were used for the analysis. TSA revealed the current sample size already demonstrated superiority of DOACs in LV thrombus resolution and stroke, and futility in any thromboembolism and all-cause death. Two other outcomes did not achieve the required sample size. The sample size of new trials needed to demonstrate the superiority of DOACs over VKAs was estimated 400 for any bleeding. Corresponding trials needed to demonstrate no significant differences could be estimated for major bleeding and any bleeding (n = 200 and n = 2000, respectively). Current results show that the sample size required to draw definite conclusions was not reached for two outcomes, and there was a risk of random error. Further randomized controlled trials with sample sizes estimated by TSA will work effectively to obtain valid conclusions.

Edoxaban treatment in atrial fibrillation in routine clinical care: One-year outcomes of the prospective observational ETNA-AF study in South Korean patients

BACKGROUND

The real-world outcomes of edoxaban treatment in patients with atrial fibrillation (AF) were analyzed in the ETNA-AF (Edoxaban Treatment in Routine Clinical Practice) study involving data from multiple regional registries. This report addresses effectiveness and safety of edoxaban in the Korean ETNA-AF population.

METHODS

One-year data from 1887 Korean ETNA-AF participants were analyzed according to edoxaban dose and patient age and compared with results of other ETNA-AF registries.

RESULTS

Approximately 70% of patients received the recommended doses of edoxaban (60 mg/30 mg); non-recommended 60 mg and 30 mg doses were prescribed to 9.6% and 19.8% of the patients, respectively. The proportions of reference age (<65 years), youngest-old (65-74 years) and middle-old/oldest-old (≥75 years) groups were 21.4%, 40.2%, and 38.4%, respectively. Incidence of major or clinically relevant nonmajor bleeding was similar within dose (0.57%-1.71%) and age subgroups (1.26%-1.63%). Incidence of net clinical outcome, a composite of stroke, systemic embolic event, major bleeding, and all-cause mortality, was also comparable among dose subgroups (1.14%-3.10%) and age subgroups (2.28%-2.78%). The percentage of Korean patients receiving non-recommended 30 mg (19.8%) was over twice that of the European population (8.4%). However, the clinical outcomes were generally similar among different populations included in the ETNA-AF study.

CONCLUSIONS

The outcomes in the Korean ETNA-AF population are like those in the global ETNA-AF population, with overall low event rates of stroke, major bleeding and all-cause mortality across age and dose subgroups. Edoxaban can be used effectively and safely in specific populations of Korean AF patients, including the elderly.

DOACs in the Anticoagulation of Mechanical Valves: A Systematic Review and Future Perspectives

Valvular heart disease is a common disease often necessitating valve replacement. Mechanical heart valves (MHVs) are often used in younger patients because of their longer durability. Their main disadvantage is the need for lifelong anticoagulation. Warfarin is considered a standard treatment, but it is far from perfect. Direct oral anticoagulants (DOACs) are a new and more patient-friendly alternative to warfarin when anticoagulation is required, but have not yet been approved for the indication of mechanical valves.

EVIDENCE ACQUISITION

A literature search of Pubmed, Embase, Web of Science (Core Collection), and Cochrane Library (from inception to May 2023) was performed using a search string that was well defined and not modified during the study. An extensive overview of the search terms used in each database can be found in the Appendix. Only prospective clinical trials were included in this review. A total of 10 publications were included in this review.

RELEVANCE TO CLINICAL PRACTICE

This systematic review summarizes the different types of DOACs and their possible use in the anticoagulation of mechanical valves. We aim to propose future directions in anticoagulation research for mechanical valves.

CONCLUSIONS

DOAC use in MHVs has been halted due to the failure of both dabigatran and apixaban in two major clinical trials. However, rivaroxaban was successful in two small clinical trials. Ample research is still needed to explore new valve designs as well as new anticoagulation targets.

Focal Anticoagulation by Somatic Gene Transfer: Towards Preventing Cardioembolic Stroke

Cardioembolic stroke (CS) has emerged as a leading cause of ischaemic stroke (IS); distinguished by thrombi embolising to the brain from cardiac origins; most often from the left atrial appendage (LAA). Contemporary therapeutic options are largely dependent on systemic anticoagulation as a blanket preventative strategy, yet this does not represent a nuanced or personalised solution. Contraindications to systemic anticoagulation create significant unmedicated and high-risk cohorts, leaving these patients at risk of significant morbidity and mortality. Atrial appendage occlusion devices are increasingly used to mitigate stroke risk from thrombi emerging from the LAA in patients ineligible for oral anticoagulants (OACs). Their use, however, is not without risk or significant cost, and does not address the underlying aetiology of thrombosis and CS. Viral vector-based gene therapy has emerged as a novel strategy to target a spectrum of haemostatic disorders, achieving success through the adeno-associated virus (AAV) based therapy of haemophilia. Yet, thrombotic disorders, such as CS, have had limited exploration within the realm of AAV gene therapy approaches-presenting a gap in the literature and an opportunity for further research. Gene therapy has the potential to directly address the cause of CS by localised targeting of the molecular remodelling that serves to promote thrombosis.

Influence of Surface-Modification via PEGylation or Chitosanization of Lipidic Nanocarriers on In Vivo Pharmacokinetic/Pharmacodynamic Profiles of Apixaban

Nanostructured lipid carriers (NLCs) have been proven to significantly improve the bioavailability and efficacy of many drugs; however, they still have many limitations. These limitations could hinder their potential for enhancing the bioavailability of poorly water-soluble drugs and, therefore, require further amendments. From this perspective, we have investigated how the chitosanization and PEGylation of NLCs affected their ability to function as a delivery system for apixaban (APX). These surface modifications could enhance the ability of NLCs to improve the bioavailability and pharmacodynamic activity of the loaded drug. In vitro and in vivo studies were carried out to examine APX-loaded NLCs, chitosan-modified NLCs, and PEGylated NLCs. The three nanoarchitectures displayed a Higuchi-diffusion release pattern in vitro, in addition to having their vesicular outline proven via electron microscopy. PEGylated and chitosanized NLCs retained good stability over 3 months, versus the nonPEGylated and nonchitosanized NLCs. Interestingly, APX-loaded chitosan-modified NLCs displayed better stability than the APX-loaded PEGylated NLCs, in terms of mean vesicle size after 90 days. On the other hand, the absorption profile of APX (AUC_0-inf) in rats pretreated with APX-loaded PEGylated NLCs (108.59 µg·mL^-1·h^-1) was significantly higher than the AUC_0-inf of APX in rats pretreated with APX-loaded chitosan-modified NLCs (93.397 µg·mL^-1·h^-1), and both were also significantly higher than AUC_0-inf of APX-Loaded NLCs (55.435 µg·mL^-1·h^-1). Chitosan-coated NLCs enhanced APX anticoagulant activity with increased prothrombin time and activated partial thromboplastin time by 1.6- and 1.55-folds, respectively, compared to unmodified NLCs, and by 1.23- and 1.37-folds, respectively, compared to PEGylated NLCs. The PEGylation and chitosanization of NLCs enhanced the bioavailability and anticoagulant activity of APX over the nonmodified NLCs; this highlighted the importance of both approaches.

Direct-Acting Oral Anticoagulant Therapy in Cancer Patients-A Review

Venous thromboembolism (VTE) is an important aspect in cancer patients. There are various pharmacological methods used for thrombotic event treatment. DOACs (direct-acting oral anticoagulants) are gaining popularity among both physicians and researchers and are slowly starting to replace VKAs (vitamin K antagonists), thus becoming a substitute or alternative option for LMWHs (low-molecular-weight heparins). In this article, we present DOACs' main therapeutic advantages and disadvantages in patients with cancer. The only major concern with using DOACs is the higher risk of bleeding; however, there are discrepancies in this matter. There are still some types of cancer for which DOACs are not recommended. Specific cancer types may influence the efficacy of DOAC therapy. Additionally, race and ethnicity may affect therapy in cancer patients with DOACs. A sizeable number of clinical trials are focused on comparing DOACs with other anticoagulants. The current guidelines of different scientific associations are not unanimous in their DOAC assessments. There is still a need for more evidence of DOACs' potential advantages over other methods of anticoagulation in cancer patients to facilitate their position in this recommendation. This literature review presents the current state of knowledge about the use of DOACs in patients with neoplastic growth.

Direct oral anticoagulants: patient reported adherence and minor bleedings

Data regarding adherence and minor bleeding on direct oral anticoagulants in everyday life are still sparse. Inclusion criteria: treatment initiated with dabigatran, rivaroxaban or apixaban in non-valvular atrial fibrillation patients from a center in northern Sweden between 2011 and 2019 (n = 668). Exclusion criteria: cognitive impairment, dose dispensing, need of interpreter or hospital admission (n = 67). By a telephone interview adherence was measured in 569 patients (response rate 94.8%) using the 8-item Morisky medication adherence scale and minor bleeding was asked for. CHA₂DS₂-VASc and HAS-BLED scores were collected from medical records. The number (n), mean age, mean treatment duration, mean (points) CHA₂DS₂-VASc and HAS-BLED scores was with dabigatran (n = 175, 73.3 years, 17.8 months, 3.6 p and 2.2 p), rivaroxaban (n = 198, 73.7 years, 21months, 3.8 p and 2.1 p) and apixaban (n = 196, 72.7 years, 15.2 months, 3.4 p and 2.1 p). Adherence was high for dabigatran, rivaroxaban and apixaban in 54%, 76% and 53%; intermediate in 37%, 20% and 37% or low in 9%, 4% and 10% respectively. High adherence (Morisky score 8) distinguished rivaroxaban (p < 0.0001) and in patients with CHA₂DS₂-VASc ≥ 4 p, (p < 0.0001). Patients on rivaroxaban/apixaban reported more minor bleedings (37% / 28%) compared to dabigatran (13%), (p < 0.001). Only 61% of the patients followed prescription. Adherence to rivaroxaban was significantly better, maybe due to the once daily dosing regimen, and furthermore among patients with higher risk for stroke. Minor bleedings were less common in the dabigatran group. The impact of minor bleedings on adherence and a possible relationship to clinical outcomes need to be further studied.

Clinical outcomes and predictors of a gap in direct-acting oral anticoagulant therapy in the elderly: A time-varying analysis of a nationwide cohort study

INTRODUCTION

As direct-acting oral anticoagulants (DOACs) have short half-lives of around 12 h, even a short gap in DOAC therapy may diminish anticoagulation effects, increasing risks of adverse clinical outcomes. We aimed to evaluate clinical consequences of a gap in DOAC therapy with atrial fibrillation (AF) and to identify its potential predictors.

MATERIALS AND METHODS

In this retrospective cohort study, we included DOAC users aged over 65 years with AF from the 2018 Korean nationwide claims database. We defined a gap in DOAC therapy as no claim for a DOAC one or more days after the due date of a refill prescription. We used a time-varying-analysis method. The primary outcome was a composite of death and thrombotic events including ischemic stroke/transient ischemic attack or systemic embolism. Potential predictors of a gap included sociodemographic and clinical factors.

RESULTS AND CONCLUSIONS

Among 11,042 DOAC users, 4857 (44.0 %) patients had at least one gap. Standard national health insurance, non-metropolitan locations of medical institutions, history of liver disease, chronic obstructive pulmonary disease, cancer, or dementia, and use of diuretics or non-oral agents were associated with increased risks of a gap. In contrast, history of hypertension, ischemic heart disease, or dyslipidemia were associated with a decreased risk of a gap. A short gap in DOAC therapy was significantly associated with a higher risk of the primary outcome compared to no gap (hazard ratio 4.04, 95 % confidence interval 2.95-5.52). The predictors could be utilized to identify at-risk patients to provide additional support to prevent a gap.

Cost-Effectiveness of Screening to Identify Patients With Atrial Fibrillation: A Systematic Review

BACKGROUND

Screening for Atrial Fibrillation (AF) is recommended for people aged above 65 years. Screening for AF in asymptomatic individuals can be beneficial by enabling earlier diagnosis and the commencement of interventions to reduce the risk of early events, thus improving patient outcomes. This study systematically reviews the literature about the cost-effectiveness of various screening methods for previously undiagnosed AF.

METHODS

Four databases were searched to identify articles that are cost-effectiveness studies conducted on screening for AF published from January 2000 to August 2022. The Consolidated Health Economic Evaluation Reporting Standards 2022 checklist was used to assess the quality of the selected studies. A previously published approach was used to assess the usefulness of each study for health policy makers.

RESULTS

The database search yielded 799 results, with 26 articles meeting the inclusion criteria. Articles were categorised into four subgroups: (i) population screening, (ii) opportunistic screening, (iii) targeted, and (iv) mixed methods of screening. Most of the studies screened adults ≥65 years of age. Most studies were performed from a 'health care payer perspective' and almost all studies used 'not screening' as a comparator. Almost all screening methods assessed were found to be cost-effective in comparison to 'not screening'. The reporting quality varied between 58% to 89%. The majority of the studies were found to be of limited usefulness for health policy makers, as none of the studies made any clear statements about policy change or implementation direction.

CONCLUSION

All approaches of AF screening were found to be cost-effective compared with no screening, while opportunistic screening was found to be the optimal approach in some studies. However, screening for AF in asymptomatic individuals is context specific and likely to be cost-effective depending on the population screened, screening approach, frequency, and the duration of screening.

Mortality on DOACs Versus on Vitamin K Antagonists in Atrial Fibrillation: Analysis of the Hungarian Health Insurance Fund Database

PURPOSE

Limited real-world data are available on the survival of patients treated with vitamin K antagonists (VKAs) versus with direct oral anticoagulants (DOACs) for nonvalvular atrial fibrillation (AF). In this nationwide registry, we analyzed the mortality risk of patients with nonvalvular AF taking DOACs versus VKAs, with a special attention to the early treatment period.

METHODS

The Hungarian National Health Insurance Fund (NHIF) database was searched to identify patients treated with VKA or DOAC as a thromboembolic prophylaxis for nonvalvular AF between 2011 and 2016. The overall and the early (0-3, 4-6, and 7-12 months) mortality risks with the 2 types of anticoagulation were compared. A total of 144,394 patients with AF treated with either a VKA (n = 129,925) or a DOAC (n = 14,469) were enrolled.

FINDINGS

A 28% improvement in 3-year survival with DOAC treatment compared with VKA treatment was shown. Mortality reduction with DOACs was consistent across different subgroups. However, younger patients (30-59 years old) initiated on DOAC therapy had the greatest RRR (53%) in mortality. Furthermore, DOAC treatment also yielded a benefit of greater magnitude (HR = 0.55; 95% CI, 0.40-0.77, P = 0.001) in the lower (0-1) CHA₂DS₂-VASc score segment and in those with fewer (0-1) bleeding risk factors (HR = 0.50, CI 0.34-0.73, P = 0.001). The RRR in mortality with DOACs was 33% within the first 3 months, and 6% in the second year.

IMPLICATIONS

Thromboembolic prophylaxis with DOACs in this study yielded significantly lower mortality compared with VKA treatment in patients with nonvalvular AF. The largest benefit was shown in the early period after treatment initiation, as well as in younger patients, those with a lower CHA₂DS₂-VASc score, and those with fewer bleeding risk factors.

Effectiveness and Safety of Apixaban vs Warfarin in Patients with Venous Thromboembolism with Risk Factors for Bleeding or for Recurrences

INTRODUCTION

Patients at increased risk of bleeding and recurrent VTE who develop venous thromboembolism (VTE) present challenges for clinical management. This study evaluated the effectiveness and safety of apixaban vs warfarin in patients with VTE who have risk factors for bleeding or recurrences.

METHODS

Adult patients with VTE initiating apixaban or warfarin were identified from five claims databases. Stabilized inverse probability treatment weighting (IPTW) was used to balance characteristics between cohorts for the main analysis. Subgroup interaction analyses were conducted to evaluate treatment effects among patients with and without each of the conditions that increased the risk of bleeding (thrombocytopenia and history of bleed) or recurrent VTE (thrombophilia, chronic liver disease, and immune-mediated disorders).

RESULTS

A total of 94,333 warfarin and 60,786 apixaban patients with VTE met selection criteria. After IPTW, all patient characteristics were balanced between cohorts. Apixaban (vs warfarin) patients were at lower risk of recurrent VTE (HR [95% confidence interval (CI) 0.72 [0.67-0.78]), major bleeding (MB) (HR [95% CI] 0.70 [0.64-0.76]), and clinically relevant non-major (CRNM) bleeding (HR [95% CI] 0.83 [0.80-0.86]). Subgroup analyses showed generally consistent findings with the overall analysis. For most subgroup analyses, there were no significant interactions between treatment and subgroup strata on VTE, MB and CRNM bleeding.

CONCLUSION

Patients with prescription fills for apixaban had lower risk of recurrent VTE, MB, and CRNM bleeding compared with warfarin patients. Treatment effects of apixaban vs warfarin were generally consistent across subgroups of patients at increased risk of bleeding/recurrences.

Medication errors in relation to direct-acting oral anticoagulants: a qualitative study of pharmacists' views and experiences

BACKGROUND

Despite their effectiveness and ease of use, medication errors have been reported to be highly prevalent with direct-acting oral anticoagulants (DOAC).

AIM

The aim of this study was to explore views and experiences of pharmacists on contributory factors and mitigation strategies around medication errors in relation to DOAC.

METHOD

This study used a qualitative design. Semi-structured interviews were conducted with hospital pharmacists in Saudi Arabia. The interview topic guide was developed based on previous literature and Reason's Accident Causation Model. All interviews were transcribed verbatim and MAXQDA Analytics Pro 2020 was used to thematically analyse the data (VERBI Software).

RESULTS

Twenty-three participants representing a range of experiences participated. The analysis recognised three major themes: (a) enablers and barriers faced by pharmacists in promoting safe utilisation of DOAC, such as opportunities to conduct risk assessments and offer patient counselling (b) factors related to other healthcare professionals and patients, such as opportunities for effective collaborations and patient health literacy; and (c) effective strategies to promote DOAC safety such as empowering the role of pharmacists, patient education, opportunities for risk assessments, multidisciplinary working and enforcement of clinical guidelines and enhanced roles of pharmacists.

CONCLUSION

Pharmacists believed that enhanced education of healthcare professionals and patients, development and implementation of clinical guidelines, improvement of incident reporting systems, and multidisciplinary team working could be effective strategies to reduce DOAC-related errors. In addition, future research should utilise multifaceted interventions to reduce error prevalence.

Personalizing Direct Oral Anticoagulant Therapy for a Diverse Population: Role of Race, Kidney Function, Drug Interactions, and Pharmacogenetics

Oral anticoagulants (OACs) are commonly used to reduce the risk of venous thromboembolism and the risk of stroke in patients with atrial fibrillation. Endorsed by the American Heart Association, American College of Cardiology, and the European Society of Cardiology, direct oral anticoagulants (DOACs) have displaced warfarin as the OAC of choice for both conditions, due to improved safety profiles, fewer drug-drug and drug-diet interactions, and lack of monitoring requirements. Despite their widespread use and improved safety over warfarin, DOAC-related bleeding remains a major concern for patients. DOACs have stable pharmacokinetics and pharmacodynamics; however, variability in DOAC response is common and may be attributed to numerous factors, including patient-specific factors, concomitant medications, comorbid conditions, and genetics. Although DOAC randomized controlled trials included patients of varying ages and levels of kidney function, they failed to include patients of diverse ancestries. Additionally, current evidence to support DOAC pharmacogenetic associations have primarily been derived from European and Asian individuals. Given differences in genotype frequencies and disease burden among patients of different biogeographic groups, future research must engage diverse populations to assess and quantify the impact of predictors on DOAC response. Current under-representation of patients from diverse racial groups does not allow for proper generalization of the influence of clinical and genetic factors in relation to DOAC variability. Herein, we discuss factors affecting DOAC response, such as age, sex, weight, kidney function, drug interactions, and pharmacogenetics, while offering a new perspective on the need for further research including frequently excluded groups.

Efficacy and safety of direct oral anticoagulants versus vitamin K antagonists for left ventricular thrombus: an updated systematic review and meta-analysis

Aim    To perform a systematic review and meta-analysis of efficacy and safety of direct oral anticoagulants (DOAC) as compared to vitamin K antagonists (VKA) in the treatment of left ventricular (LV) thrombosis.Material and methods    A search was performed in PubMed and Google Scholar for studies that compared DOAC and VKA in the treatment of LV thrombosis with respect of thromboembolic events, hemorrhagic complications, and thrombus resolution. The effect was evaluated with the odds ratio (OR) that was computed using a fixed effects model.Results    For these systematic review and meta-analysis, 19 studies were selected, including 2 randomized and 17 cohort studies. The articles included into these systematic review and meta-analysis, were published from 2018 through 2021. In total, 2970 patients (mean age, 58.8 лет; 1879 (61.2 %) men) with LV thrombus were included into the meta-analysis. Mean follow-up duration was 17.9 months. The meta-analysis showed no significant difference between DOAC and VKA in the incidence of the study outcomes: thromboembolic events (OR, 0.86; 95 % CI: 0.67-1.10; р=0.22), hemorrhagic complications (OR, 0.77; 95 % CI: 0.55-1.07; р=0.12), thrombus resolution (OR, 0.96; 95 % CI: 0.76-1.22; р=0.77). In a subgroup analysis, rivaroxaban compared to VKA significantly (79%) reduced the risk of thromboembolic complications (OR, 0.21; 95 % CI: 0.05-0.83; р=0.03) with no significant differences in hemorrhagic events (OR, 0.60; 95 % CI: 0.21-1.71; р=0.34) or thrombus resolution (OR, 1.44; 95 % CI: 0.83-1.31; р=0.20). The apixaban treatment group had significantly more (4.88 times) cases of thrombus resolution than the VKA treatment group (OR, 4.88; 95 % CI: 1.37-17.30; р=0.01); for apixaban, data on hemorrhagic and thromboembolic complications were not available.Conclusions    The therapeutic efficacy and side effects of the DOAC treatment for LV thrombosis were similar to those of VKA with respect of thromboembolic events, hemorrhage, and thrombus resolution.

A Cardiologists’ Survey on the Use of Anticoagulants and Antiplatelets in Patients With Atrial Fibrillation and Acute Coronary Syndrome or Those Undergoing Percutaneous Coronary Intervention in India

PURPOSE

The management of patients with atrial fibrillation (AF) and acute coronary syndrome (ACS) or undergoing percutaneous coronary intervention (PCI) requires appropriate antithrombotic regimens for stroke prevention and in-stent thrombosis. Current practice recommendations are largely based on consensus options as there is limited evidence from randomized clinical trials. Hence, by surveying a group of cardiologists across India, we sought to better understand the current practice patterns of using oral anticoagulants (vitamin K antagonist, VKA or non-vitamin K antagonist oral anticoagulant, NOAC) and antiplatelet therapy in those patients in India.

METHODS

A cross-sectional questionnaire-based survey was conducted across India to better understand the clinical practices in AF management.

RESULTS

A total of 151 cardiologists participated in this survey. The most commonly prescribed combination therapy in patients with AF and ACS/undergoing PCI was triple therapy (NOAC + dual antiplatelet [aspirin and P2Y12 inhibitor]) (54.30%) followed by NOAC + single antiplatelet (33.11%). Only 11.26% of cardiologists prescribed VKA + dual antiplatelet therapy. Among anticoagulants, cardiologists prescribed NOACs to 66.11% of patients and VKAs to 25.54% of patients. Among P2Y12 inhibitors, ticagrelor (50.99%) and clopidogrel (47.02%) were the most preferred medication. The physician reported patient adherence rates to NOACs were higher compared to VKAs. Around 41.06% of cardiologists reportedly changed antiplatelet therapy for patients from dual antiplatelet to single antiplatelet therapy in three months; 36.42%, in one month; and 19.21% in six months after PCI. Around 61.59% of cardiologists stopped prescribing antiplatelet therapy for patients by one year.

CONCLUSION

Our survey demonstrated that the majority of cardiologists used triple therapy (NOAC + dual antiplatelet), followed by NOAC + single antiplatelet for managing patients with AF and ACS or undergoing PCI in line with the available guidelines.

Aneurysmal Subarachnoid Hemorrhage in Hospitalized Patients on Anticoagulants-A Two Center Matched Case-Control Study

Objective-Direct oral anticoagulants (DOAC) are replacing vitamin K antagonists (VKA) for the prevention of ischemic stroke and venous thromboembolism. We set out to assess the effect of prior treatment with DOAC and VKA in patients with aneurysmal subarachnoid hemorrhage (SAH). Methods-Consecutive SAH patients treated at two (Aachen, Germany and Helsinki, Finland) university hospitals were considered for inclusion. To assess the association between anticoagulant treatments on SAH severity measure by modified Fisher grading (mFisher) and outcome as measured by the Glasgow outcome scale (GOS, 6 months), DOAC- and VKA-treated patients were compared against age- and sex-matched SAH controls without anticoagulants. Results-During the inclusion timeframes, 964 SAH patients were treated in both centers. At the time point of aneurysm rupture, nine patients (0.93%) were on DOAC treatment, and 15 (1.6%) patients were on VKA. These were matched to 34 and 55 SAH age- and sex-matched controls, re-spectively. Overall, 55.6% of DOAC-treated patients suffered poor-grade (WFNS_4-5) SAH compared to 38.2% among their respective controls (p = 0.35); 53.3% of patients on VKA suffered poor-grade SAH compared to 36.4% in their respective controls (p = 0.23). Neither treatment with DOAC (aOR 2.70, 95%CI 0.30 to 24.23; p = 0.38), nor VKA (aOR 2.78, 95%CI 0.63 to 12.23; p = 0.18) were inde-pendently associated with unfavorable outcome (GOS_1-3) after 12 months. Conclusions-Iatrogenic coagulopathy caused by DOAC or VKA was not associated with more severe radiological or clinical subarachnoid hemorrhage or worse clinical outcome in hospitalized SAH patients.

Research progress of nephrotic syndrome accompanied by thromboembolism

Thromboembolism (TE) is a common and serious complication of nephrotic syndrome (NS). NS is associated with hypercoagulability, which may be induced by changes in coagulation, anticoagulant, and fibrinolytic factors. Moreover, accumulating evidence supports the hypothesis that the complex interactions between genetic and acquired risk factors in TE should be considered and that genetic susceptibility should not be ignored. Extracellular vesicles (EVs) also play unique roles. Further research on EVs may provide new insights into the discovery and treatment of TE associated with NS. The occurrence of NS accompanied by TE may be associated with various risk factors. Preventive anticoagulant therapy can not only reduce the risk of TE in patients but also aggravate the risk of bleeding. Heparin and vitamin K antagonists (VKAs), traditional anticoagulant drugs, have been extensively applied in the prevention and treatment of thromboembolic diseases, and emerging direct oral anticoagulants (DOACs) also provide an alternative choice. Owing to the particularity of NS, the safe application of DOACs still needs to be addressed. This review aimed to comprehensively describe the pathophysiology of TE in NS, as well as analyze the associated risk factors, the opportunity for preventive anticoagulation, and current anticoagulant information.

INVICTUS: Vitamin K antagonists remain the standard of care for rheumatic heart disease-associated atrial fibrillation

INTRODUCTION

Rheumatic heart disease (RHD) remains a major healthcare problem. Atrial fibrillation (AF) is the commonest sustained arrhythmia in RHD, leading to major complications and morbidity in a young population. Currently, anticoagulation with vitamin K antagonists (VKA) is the mainstay of therapy for the prevention of thromboembolic adverse events. However, effective use of VKA remains challenging, especially in developing countries, showing a need for alternatives. Novel oral anticoagulants (NOACs), including rivaroxaban, could form a safe and effective alternative to fulfil a major unmet need in RHD patients with AF. However, until recently, no data was available for the use rivaroxaban in patients with rheumatic heart disease associated AF. Study and Results: The INVICTUS trial was conducted to assess efficacy and safety of once-daily rivaroxaban compared with a dose-adjusted VKA for the prevention of cardiovascular events in patients with RHD-associated AF. A total of 4531 patients (age: 50.5 ± 14.6 years) were followed for 3.1 ± 1.2 years in which 560/2292 patients in the rivaroxaban group and 446/2273 in the VKA group had a primary-outcome adverse event. The restricted mean survival time was 1599 days in the rivaroxaban group and 1675 days in the VKA group (difference, -76 days; 95% confidence interval [CI], -121 to -31; P <0.001). A higher incidence of death occurred in the rivaroxaban group than in the VKA group (restricted mean survival time, 1608 days vs. 1680 days; difference, -72 days; 95% CI, -117 to -28). No significant between-group difference in the rate of major bleeding was noted.

LESSONS LEARNED

The INVICTUS trial shows that Rivaroxaban is inferior to Vitamin K-antagonists in patients with RHD associated AF as VKA therapy led to a lower rate of ischemic and lower mortality due to vascular causes, without significantly increasing the rate of major bleeding. The results support current guidelines, which recommend vitamin K antagonist therapy for the prevention of stroke in patients with RHD associated AF.

Efficacy of 11 anticoagulants for the prevention of venous thromboembolism after total hip or knee arthroplasty: A systematic review and network meta-analysis

BACKGROUND

To systematically review the efficacy of 11 anticoagulants in the treatment of venous thromboembolism (VTE) after total hip or knee arthroplasty.

METHODS

PubMed, Cochrane Library, Embase, Web of Science, China National Knowledge Infrastructure, Wanfang Data, VIP, and China Biology Medicine databases were electronically searched for studies assessing the efficacy of different anticoagulants for the prevention of VTE after total hip or knee arthroplasty from January 1, 2010, to January 27, 2022. Two reviewers independently screened the literature, extracted data, and graded the evidence using Confidence in Network Meta-Analysis. The network meta-analysis was then performed using Stata 16.0 software and R 4.1.0 software.

RESULTS

A total of 61 articles were included. The results of network meta-analysis showed that apixaban, edoxaban, fondaparinux, rivaroxaban, and darexaban were the most effective anticoagulants for the prevention of deep vein thrombosis in patients undergoing total hip or knee arthroplasty (P < .05), while there was no difference in the efficacy among the anticoagulants for the prevention of pulmonary embolism (P > .05).

CONCLUSION

Apixaban, edoxaban, fondaparinux, rivaroxaban, and darexaban have the best efficacy for the prevention of VTE after total hip or knee arthroplasty.

Evidence-based Management of Major Bleeding in Patients Receiving Direct Oral Anticoagulants: An Updated Narrative Review on the Role of Specific Reversal Agents

The indications of direct oral anticoagulants (DOACs) have expanded over the past 15 years. DOACs are effective and safe oral anticoagulants associated with lower bleeding risks and mortality than vitamin K antagonists. However, DOAC users are prone to a considerable bleeding risk, which can occur at critical sites or lead to severe life-threatening conditions. Recent statistics indicated that major bleeding occurs in up to 6.62 DOAC users per 100 treatment years. With the increased use of DOACs in clinical practice, DOAC-associated major bleeding is expected to be encountered more frequently in the emergency department. The current international guidelines recommend specific reversal agents for the management of DOAC users with severe bleeding to reverse the anticoagulant effect and restore normal hemostasis. An individualized assessment was incorporated in specific clinical situations to guide the decision pathway of major bleeding management. However, specific reversal agents are unavailable or have limited availability in many countries, which is expected to negatively impact the clinical outcomes of DOAC-associated major bleeding. Limited real-world evidence is available from these countries regarding the clinical outcomes of patients with DOAC-associated major bleeding. This narrative review provided an updated assessment of the evidence-based approaches for the management of major bleeding in DOAC users. We also explored the clinical outcomes of patients with major bleeding from clinical settings where specific reversal agents are unavailable.

Tailoring Apixaban in Nanostructured Lipid Carrier Enhancing Its Oral Bioavailability and Anticoagulant Activity

Apixaban (Apx), an oral anticoagulant drug, is a direct factor Xa inhibitor for the prophylaxis against venous thromboembolism. Apx has limited oral bioavailability and poor water solubility. The goal of this study was to improve the formulation of an Apx-loaded nanostructured lipid carrier (NLC) to increase its bioavailability and effectiveness. As solid lipid, liquid lipid, hydrophilic, and lipophilic stabilizers, stearic acid, oleic acid, Tween 80, and lecithin were used, respectively. Utilizing Box-Behnken design, the effects of three factors on NLC particle size (Y₁), zeta potential (Y₂), and entrapment efficiency percent (Y₃) were examined and optimized. The optimized formula was prepared, characterized, morphologically studied, and pharmacokinetically and pharmacodynamically assessed. The observed responses of the optimized Apx formula were 315.2 nm, -43.4 mV, and 89.84% for Y₁, Y₂, and Y₃, respectively. Electron microscopy revealed the homogenous spherical shape of the NLC particles. The in vivo pharmacokinetic study conducted in male Wistar rats displayed an increase in AUC and C_max by 8 and 2.67 folds, respectively, compared to oral Apx suspension. Moreover, the half-life was increased by 1.94 folds, and clearance was diminished by about 8 folds, which makes the NLC formula a promising sustained release system. Interestingly, the pharmacodynamic results displayed the superior effect of the optimized formula over the drug suspension with prolongation in the cuticle bleeding time. Moreover, both prothrombin time and activated partial thromboplastin time are significantly increased. So, incorporating Apx in an NLC formula significantly enhanced its oral bioavailability and pharmacodynamic activity.

Time trends in antithrombotic therapy prescription patterns: Real-world monocentric study in hospitalized patients with atrial fibrillation

BACKGROUND

Since 2010, the European Society of Cardiology has extended prescription criteria for oral antithrombotic therapy (OAT) in atrial fibrillation (AF). Direct oral anticoagulants (DOACs) were upgraded from an IIAa recommendation in 2012 to an IA in 2016. In real-world scenarios, however, OAC prescription is still suboptimal, mainly for DOACs.

AIM

To evaluate OAT temporal prescription patterns in a cohort of patients hospitalized with AF in a Cardiology Department.

METHODS

A retrospective observational study was conducted on a cohort of hospitalized patients in a secondary setting (Trapani, Italy) from 2010 to 2021 with AF as the main or secondary diagnosis. For 4089 consecutive patients, the variables extracted from the Cardiology department database were: Sex, age, time of hospitalization, antithrombotic therapy (warfarin, acenocoumarol, apixaban, dabigatran, edoxaban, rivaroxaban, aspirin, clopidogrel, other antiplatelet agents, low molecular weight heparin, and fondaparinux), diagnosis at discharge and used resources. Basal features are presented as percentage values for categorized variables and as mean +/- SD for categorized once.

RESULTS

From January 1st, 2010 to October 6th, 2021, 25132 patients were hospitalized in our department; 4089 (16.27%, mean age 75.59+/-10.82) were discharged with AF diagnosis; of them, 2245 were males (54.81%, mean age 73.56+/-11.45) and 1851 females (45.19%, mean age 78.06+/-9.47). Average length of stay was 5.76+/-4.88 days; 154 patients died and 88 were moved to other Departments/Structures. AF was the main diagnosis in 899 patients (21.94%). The most frequent main diagnosis in patients with AF was acute myocardial infarction (1973 discharges, 48.19%). The most frequent secondary cardiac diagnosis was chronic coronary syndrome (1864 discharges, 45.51%), and the most frequent secondary associated condition was arterial hypertension (1010 discharges, 24.66%). For the analysis of antithrombotic treatments, the final sample included 3067 patients, after excluding in-hospital deaths, transferred out or self-discharged patients, as well as discharges lacking indications for prescribed treatments. OAC treatment increased significantly (35.63% in 2010-2012 vs 61.18% in 2019-2021, +25.55%, P < 0.0001), in spite of any antiplatelet agent use. This rise was due to increasing use of DOACs, with or without antiplatelet agents, from 3.04% in 2013-2015 to 50.06% in 2019-2021 (+47.02%, P < 0.0001) and was greater for factor Xa inhibitors, especially apixaban. In addition, treatment with a vitamin K antagonist, in spite of any antiplatelet agent use, decreased from 35.63% in 2010-2012 to 11.12% in 2019-2021 (-24.48%, P < 0.0001), as well as any antiplatelet therapy, alone or in double combination, (49.18% in 2010-2012 vs 34.18% in 2019-2021, -15.00%, P < 0.0001); and patients not receiving antithrombotic therapy declined with time (14.58% in 2010-2012 vs 1.97% in 2021, P < 0.0001).

CONCLUSION

Real-world patients with AF are elderly and affected by cardiovascular and non-cardiovascular diseases. The percentage of patients on OAT and DOACs increased. These data suggest a slow, gradual guidelines implementation process.

Clinical significance of the series of CYP2C9*non3 variants, an unignorable predictor of warfarin sensitivity in Chinese population

Backgrounds

Gene polymorphisms are critical for variations in warfarin dose. To date, more than 70 CYP2C9 alleles have been identified. This study was designed to clarify the clinical significance of CYP2C9*non-3 variants to warfarin sensitivity in Chinese Han patients.

Methods

The entire CYP2C9 gene region was sequenced in 1,993 individuals, and clinical data and VKORC1 genotypes were collected from 986 patients with atrial fibrillation treated with warfarin. The SKAT-O method was used to analyze the effects of CYP2C9*non-3 variants on warfarin sensitivity.

Results

A total of 20 CYP2C9 variants were identified, of which four were novel. Carriers with CYP2C9*non-3 variants may have lower warfarin dose requirements, and similar to CYP2C9*3, CYP2C9*non-3 variants are clearly relevant to warfarin-sensitive and highly sensitive responders.

Conclusion

Our results showed that, besides CYP2C9*3, the series of CYP2C9*non-3 variants is an unignorable predictor for warfarin sensitivity in Chinese population. From a safety consideration, people carried such variants may need a preferred choice of NOACs when they started anticoagulation therapy.

Diversity of pharmacogenomic variants affecting warfarin metabolism in Sri Lankans

Aims: To describe the diversity of pharmacogenomic variants affecting warfarin metabolism in Sri Lankans. Materials & methods: Genotype data were filtered out from an anonymized database of 400 Sri Lankans, and minor allele frequencies (MAF) were calculated. Variants of CYP2C9, VKORC1 and CYP4F2 genes were studied. Results: Overall, CYP2C9*2 and CYP2C9*3 alleles had MAFs of 2.25% (95% CI: 0.80–3.70) and 10.38% (95% CI: 7.50–13.50), respectively. CYP2C9*11 and CYP2C9*14 alleles had MAFs of 0.13% (95% CI: 0–0.74) and 2.50% (95% CI: 0.97–4.03), respectively. MAFs of VKORC1 variants rs7294, rs9934438, rs8050894 and rs2884737 were 47.25% (95% CI: 42.36–52.14), 10.13% (95% CI: 7.28–13.22), 9.88% (95% CI: 7.06–12.94) and 4.88% (95% CI: 2.86–7.14), respectively. MAF of CYP4F2 variant rs2108622 was 45.63% (95% CI: 40.87–50.63). Conclusion: Compared with other populations, the frequencies of some studied variants were significantly different in Sri Lankans, and these are likely to account for variability in warfarin dosage requirements.

Intramural Jejunal Hematoma Causing Intermittent Bowel Obstruction—A Rare Manifestation of Warfarin Toxicity

Patients with thromboembolic disorders are commonly on anticoagulants; hence, they are susceptible to bleeding episodes such as ecchymosis, gingival, subconjunctival bleeding, and rarely can have intramural hematoma of small bowel causing patient to present with intestinal obstruction. It is a rare cause of mechanical bowel obstruction requiring a nonsurgical management.

Our patient was a 55-year-old male, a known case of thromboembolism on warfarin medication, presented with abdominal pain and vomiting. Patient's laboratory reports reflected anemia and deranged coagulation profile with prothrombin time and international normalized ratio, both being elevated. Intramural hematoma of jejunum was diagnosed by abdominal contrast-enhanced computed tomography. Conservative management was done, warfarin was stopped and vitamin K was administered. Patient received fresh frozen plasma and packed cell blood.

It is important to suspect warfarin toxicity in patients on the medication who come with such presentation to avoid surgical management, which could be catastrophic due to excessive bleeding. It is important for regular monitoring of coagulation profile of such patients and to reduce prescribing other medications that can interact with warfarin. It is worth noting that novel oral anticoagulants, such as dabigatran and rivaroxaban, are associated with fewer side effects and do not require close laboratory monitoring.

Efficacy and Safety of Direct Oral Anticoagulants in Patients With Antiphospholipid Syndrome: A Systematic Review and Meta-Analysis

Due to a high risk of recurrent thromboembolism in patients with antiphospholipid syndrome (APS), long-term anticoagulation is recommended. For decades, vitamin K antagonists (VKAs) have been the gold standard for thromboprophylaxis in these patients. Due to the widespread use of direct oral anticoagulants (DOACs) in various thromboembolic conditions and their potential advantages compared to VKAs, several studies have been conducted to evaluate their safety and efficacy in APS. We performed a literature search using PubMed, Embase, and Cochrane databases for studies comparing DOACs to VKAs in patients with APS. Relative risk (RR) and the corresponding 95% confidence intervals (95% CI) were estimated for recurrent thromboembolic events, bleeding, and mortality. A total of 1437 patients pooled from 12 studies were analyzed. The risk of recurrent thrombosis, especially arterial thrombosis, doubled with DOACs compared to VKAs (RR 2.61, 95% CI 1.44-4.71; p=0.001). The risk further increased in patients with a triple-positive antiphospholipid antibody profile (RR 4.50, 95% CI 1.91-10.63; p=0.0006) and with the use of rivaroxaban (RR 1.95, 95% CI 1.10-3.45; p=0.02). The risk of major bleeding and mortality were not significantly different between the two arms. A trend favoring DOACs compared to VKAs was observed for all bleeding events.  This meta-analysis comes in agreement with previous studies and supports the use of VKAs in APS. Our study revealed that VKAs remain the gold standard for the management of APS, especially triple-positive APS. DOACs, particularly rivaroxaban, are not as effective in preventing recurrent thromboembolism in high-risk APS patients. Further studies are needed to evaluate the role of DOACs apart from rivaroxaban with a focus on their efficacy in the management of isolated or double-positive APS.

The Influence of ABCB1 (rs1045642 and rs4148738) Gene Polymorphisms on Rivaroxaban Pharmacokinetics in Patients Aged 80 Years and Older with Nonvalvular Atrial Fibrillation

INTRODUCTION

ABCB1 gene polymorphisms are associated with rivaroxaban distribution changes and adverse reactions but the data are controversial.

AIM

To evaluate the influence of ABCB1 (rs1045642 and rs4148738) gene polymorphisms on rivaroxaban pharmacokinetics in patients aged 80 years and older with nonvalvular atrial fibrillation (NAF).

METHODS

128 patients aged 80 years and older (median [Me] age 87.5 [83.0-90.0] years) with NAF were included. We performed ABCB1 (rs1045642 and rs4148738) genotyping, measured the trough steady-state plasma concentration (C_min,ss) of rivaroxaban and prothrombin time (PT) and analyzed prior medical records for clinically relevant non-major bleeding (CRNMB).

RESULTS

CC genotype carriers had no differences in C_min,ss (p > 0.05) compared with the CT and TT rs1045642 and rs4148738 genotypes carriers. CC genotype carriers had no differences in PT (p > 0.05) compared with the CT rs1045642 and rs4148738 and TT rs4148738 genotypes carriers. In the TT genotype PT levels were higher than in the CC rs1045642 genotype: Me 14.2 [13.0-16.1] sec vs 13.3 [12.4-14.5] sec (p = 0.049). Incidence of CRNMB was higher in patients with the TT genotype compared with the CC rs1045642 (29.3% vs 4.5%, p = 0.021) and rs4148738 (39.3% vs 8.1%, p = 0.008) and the CT genotype rs4148738 (39.3% vs 14.3%, p = 0.002).

CONCLUSION

ABCB1 (rs1045642 and rs4148738) polymorphisms didn't influence rivaroxaban pharmacokinetics in patients aged 80 years and older with NAF. TT carriers developed CRNMB more frequently compared with the CC rs1045642 and the CC and CT rs4148738 genotypes. The haplotype TT-TT haplotype was associated with a higher frequency of CRNMB.

New Oral Anticoagulants Open New Horizons for Cancer Patients with Venous Thromboembolism

Venous thromboembolism (VTE) is associated with increased morbidity and mortality, decreased quality of life, and higher economic burden in patients with cancer. Currently, the treatment of VTE in patients with cancer is particularly challenging. For many years, low molecular weight heparin (LMWHs) has been the standard for the treatment of cancer-associated VTE. Recently, the introduction of new oral anticoagulants (NOACs) may offer an oral anticoagulant option for some patients with cancer-associated thrombosis (CAT) as a growing body of literature supports the use of NOACs in the setting of CAT. With the use of NOAC as a new option in the management of CAT, clinicians now face several choices for the individual cancer patient with VTE. We need a more in-depth understanding of the drug properties, efficacy and safety, economic analysis that allows us to choose the most appropriate treatment for each patient. In the review, we will present an overview of CAT management, discuss the available evidence, economic costs for NOACs in the treatment of CAT, and seek to provide the best range of treatments for cancer patients.

APIXABAN'ın DOZA BAĞLI ANTİANJİYOJENİK POTANSİYELİ: Deneysel bir bakış

Amaç: Direkt oral antikoagülanlar (DOAK'lar), tromboembolizmin tedavisi ve önlenmesi için geleneksel tıbbi rejimlere iyi alternatiflerdir. Apixaban, bu yeni geliştirilen ilaçların daha popüler varyasyonlarından biridir. Antikoagülan potansiyelinin yanı sıra, olası hücresel etkiler gelecekteki çalışmaların konusu olmaya devam etmektedir. Bu çalışmanın amacı, korioallantoik membran (CAM) modelinde apiksaban'ın olası antianjiyogenik etkilerini araştırmaktı. Yöntem: Apixaban'ın 10-4, 10-5 ve 10-6 M konsantrasyonlarında ilaç peletleri hazırlandı ve yumurta inkübasyonunun dördüncü gününde korioallantoik membrana yerleştirildi. Sekizinci günde, membranların tüm vasküler yoğunlukları, bilinen bir monoklonal, insanlaştırılmış, vasküler endotelyal büyüme faktörü inhibitörü olan 10-6 M'lik bir bevacizumab konsantrasyonu ile karşılaştırıldı. Sonuçlar: 10-4 M apiksaban konsantrasyonunun, bevacizumabınkine benzer güçlü bir antianjiyogenik potansiyele sahip olduğunu bulduk. Bununla birlikte, daha düşük bir apiksaban dozunda (10-5 M, 10-6 M) orta düzeyde antianjiyogenik potansiyel vardı. Daha yüksek antianjiyogenik potansiyel dozlarının (10-4 M konsantrasyon) daha düşük dozlarda apiksaban (10-5 M, 10-6 M) ile karşılaştırılması, önemli istatistiksel farklılıklar ortaya çıkardı (p < 0.05). Sonuç: Sonuçlarımız, yüksek doz apiksaban'ın güçlü antianjiyogenik potansiyele sahip olduğunu göstermektedir. Bu etkinin kesin mekanizması bilinmemektedir. Bu pilot sonuçlar, DOAK'lara yeni bir bakış elde etmek için daha ileri çalışmalarla doğrulanmalıdır.

Direct oral anticoagulants in patients with chronic thromboembolic pulmonary hypertension and the presence of recent thrombus during pulmonary endarterectomy

Patients with chronic thromboembolic pulmonary hypertension (CTEPH) require lifelong anticoagulant therapy. The safety and efficacy of direct oral anticoagulant (DOAC) in the chronic and transitional management of CTEPH has not been investigated. We performed a retrospective analysis of 405 consecutive pulmonary endarterectomy (PEA) cases at the University of California, San Diego, from July 2015 through July 2017. PEA specimen was reviewed for the presence of acute or subacute thrombotic material distinct from the expected chronic disease removed at the time of PEA by two investigators blinded to the patient information. Of 405 PEA cases, 166 patients (41.0%) were anticoagulated with one of three available DOACs; 239 (59.0%) presented on either oral vitamin-K antagonist or chronic injectable therapy. There were no significant differences in baseline characteristics between DOAC and non-DOAC groups. Evidence of recent thrombus was observed in 22 (13.3%) in the DOAC group versus 16 (6.7%) within the non-DOAC group. The odds ratio of DOACs usage and evidence of recent thrombus was 2.34 (95% confidence interval: 1.1-5.0, p = 0.03) after adjusting for age, gender, race, body mass index, and history of antiphospholipid antibody syndrome. CTEPH patients referred for PEA while on DOAC therapy were twice as likely to have associated acute or subacute thrombi present at the time of surgery compared with those on more traditional, non-DOAC anticoagulant therapies. This raises questions of the safety and efficacy of DOACs in the chronic management of CTEPH.