Berberine promotes the degradation of phenylacetic acid to prevent thrombosis by modulating gut microbiota.

BACKGROUND: Berberine is the main bioactive constituent of Coptis chinensis, a quaternary ammonium alkaloid. While berberine's cardiovascular benefits are well-documented, its impact on thrombosis remains not fully understood. PURPOSE: This study investigates the potential of intestinal microbiota as a novel target for preventing thrombosis, with a focus on berberine, a natural compound known for its effectiveness in managing cardiovascular conditions. METHODS: Intraperitoneal injection of carrageenan induces the secretion of chemical mediators such as histamine and serotonin from mast cells to promote thrombosis. This model can directly and visually observe the progression of thrombosis in a time-dependent manner. Thrombosis was induced by intravenous injection of 1 % carrageenan solution (20 mg/kg) to all mice except the vehicle control group. Quantitative analysis of gut microbiota metabolites through LC/MS. Then, the gut microbiota of mice was analyzed using 16S rRNA sequencing to assess the changes. Finally, the effects of gut microbiota on thrombosis were explored by fecal microbiota transplantation. RESULTS: Our research shows that berberine inhibits thrombosis by altering intestinal microbiota composition and related metabolites. Notably, berberine curtails the biosynthesis of phenylacetylglycine, a thrombosis-promoting coproduct of the host-intestinal microbiota, by promoting phenylacetic acid degradation. This research underscores the significance of phenylacetylglycine as a thrombosis-promoting risk factor, as evidenced by the ability of intraperitoneal phenylacetylglycine injection to reverse berberine's efficacy. Fecal microbiota transplantation experiment confirms the crucial role of intestinal microbiota in thrombus formation. CONCLUSION: Initiating our investigation from the perspective of the gut microbiota, we have, for the first time, unveiled that berberine inhibits thrombus formation by promoting the degradation of phenylacetic acid, consequently suppressing the biosynthesis of PAG. This discovery further substantiates the intricate interplay between the gut microbiota and thrombosis. Our study advances the understanding that intestinal microbiota plays a crucial role in thrombosis development and highlights berberine-mediated intestinal microbiota modulation as a promising therapeutic approach for thrombosis prevention.

Alleviation of endothelial dysfunction of Pheretima guillemi (Michaelsen)-derived protein DPf3 in ponatinib-induced thrombotic zebrafish and mechanisms explored through ox-LDL-induced HUVECs and TMT-based proteomics.

ETHNOPHARMACOLOGICAL RELEVANCE: Thrombus generation is one of the leading causes of death in human, and vascular endothelial dysfunction is a major contributor to thrombosis. Pheretima guillemi (Michaelsen), a traditional medicinal animal known as "Dilong", has been utilized to cure thrombotic disorders for many years. DPf3, a group of functional proteins extracted from P. guillemi, has been characterized and identified to possess antithrombotic bioactivity via in vitro and ex vivo experiments. AIM OF THE STUDY: This study is aimed to investigate the vascular-protection activity and related mechanism of antithrombotic protein DPf3 purified from Pheretima guillelmi systematically. MATERIALS AND METHODS: The antithrombotic activity and vascular endothelium protection effect of DPf3 was explored in vivo using ponatinib-induced vascular endothelial injury zebrafish thrombus model. Then, (hi) ox-LDL-induced HUVECs was applied to investigate the protection mechanism of DPf3 against the injury of vascular endothelium. In addition, TMT-based proteomics analysis was used to study the biomarkers, biological processes and signal pathways involved in the antithrombotic and vascular protective effects of DPf3 holistically. RESULTS: DPf3 exerted robust in vivo antithrombosis and vascular endothelial protection ability. DPf3 was identified to prevent HUVECs from damage by reducing ROS production, and to reduce monocyte adhesion by decreasing the protein content of adhesion factor VCAM 1. DPf3 was also observed to weaken the migration ability of injured cells and inhibit abnormal angiogenesis. The mechanism of DPf3's antithrombotic and vascular protective activity was mainly related to the regulation of lipid metabolism, energy metabolism, complement and coagulation system, ECM receptor interaction, MAPK signal pathway, etc. CONCLUSIONS: This study demonstrates that DPf3 has strong antithrombotic and endothelial protective effects. The endothelial protective ability and related mechanisms of DPf3 provide a scientific reference for the traditional use of earthworms in the treatment of thrombosis.

Supplementation with Ashitaba (Angelica keiskei) Yellow Stem Exudate Prevents Aging-Induced Thrombotic Tendencies and Systemic Inflammation Without Affecting Body Weight Gain in Mice.

Angelica keiskei Koidzumi (Ashitaba) is a traditional folk medicine and health supplement in Japan. Ashitaba yellow stem exudate (AYE) contains abundant chalcones and thus has the potential to treat and prevent many pathological states such as cancer, inflammation, obesity, diabetics, thrombosis, and hypertension. Levels of plasminogen activator inhibitor 1 (PAI-1), a key regulator of the fibrinolytic system, increase with age in mouse plasma. Therefore, we aimed to determine the effects of AYE on plasma thrombotic parameters in aging mice. Long-term (52 weeks) AYE supplementation significantly decreased age-induced increases of PAI-1 in mouse plasma. Supplementation with AYE decreased levels of the acute-phase and fibrinolytic protein plasma plasminogen, and significantly decreased those of tumor necrosis factor α. These results suggested that continuous intake of AYE throughout life decreases age-induced systemic inflammation and prevents thrombotic tendencies without affecting body weight gain in aged mice. Our findings showed that supplementing diets with AYE might help to prevent thrombotic diseases in elderly individuals.

Antithrombin III supplementation during neonatal and pediatric extracorporeal membrane oxygenation.

BACKGROUND: Bleeding and thrombosis are common extracorporeal membrane oxygenation (ECMO) complications associated with increased mortality. Heparin is the most commonly used ECMO anticoagulant, employed in 94% of cases. Reduced antithrombin III (AT3) levels could decrease heparin effectiveness. Neonates have inherently lower levels of AT3 than adults, and pediatric patients on ECMO can develop AT3 deficiency. One potential approach for patients on ECMO with AT3 deficiency is exogenous AT3 supplementation. However, there is conflicting data concerning the use of AT3 for pediatric and neonatal patients on ECMO. METHODS: We analyzed the Bleeding and Thrombosis during ECMO database of 514 neonatal and pediatric patients on ECMO. We constructed daily regression models to determine the association between AT3 supplementation and rates of bleeding and thrombosis. Given the physiological differences between pediatric patients and neonates, we constructed separate models for each. RESULTS: AT3 administration was associated with increased rates of daily bleeding among pediatric (adjusted odds ratio [aOR] 1.59, p < 0.01) and neonatal (aOR 1.37, p = 0.04) patients. AT3 supplementation did not reduce the rate of thrombosis for either pediatric or neonatal patients. CONCLUSION: AT3 administration was associated with increased rates of daily bleeding, a hypothesized potential complication of AT3 supplementation. In addition, AT3 supplementation did not result in lower rates of thrombosis. We recommend clinicians utilize caution when considering supplementing patients on ECMO with exogenous AT3.

Rivaroxaban for Prevention of Thrombotic Events, Hospitalization, and Death in Outpatients With COVID-19: A Randomized Clinical Trial.

BACKGROUND: COVID-19 (coronavirus disease 2019) is associated with heightened risks of venous and arterial thrombosis and hospitalization due to respiratory failure. To assess whether prophylactic anticoagulation can safely reduce the frequency of venous and arterial thrombosis, hospitalization, and death in nonhospitalized patients with symptomatic COVID-19 and at least one thrombosis risk factor, we conducted the PREVENT-HD double-blind, placebo-controlled randomized trial (A Study of Rivaroxaban to Reduce the Risk of Major Venous and Arterial Thrombotic Events, Hospitalization and Death in Medically Ill Outpatients With Acute, Symptomatic COVID-19] Infection). METHODS: PREVENT-HD was conducted between August 2020 and April 2022 at 14 US integrated health care delivery networks. A virtual trial design used remote informed consent and clinical monitoring and facilitated data collection through electronic health record integration with a cloud-based research platform. Nonhospitalized patients with symptomatic COVID-19 and at least one thrombosis risk factor were enrolled and randomly assigned to either 10 mg of oral rivaroxaban or placebo daily for 35 days. The primary efficacy outcome was time to first occurrence of a composite of symptomatic venous thromboembolism, myocardial infarction, ischemic stroke, acute limb ischemia, non-central nervous system systemic arterial embolism, hospitalization, or death through day 35. The principal safety end point was International Society on Thrombosis and Hemostasis critical-site or fatal bleeding. The last study visit was on day 49. RESULTS: The study was terminated prematurely because of enrollment challenges and a lower-than-expected blinded pooled event rate. A total of 1284 patients underwent randomization with complete accrual of primary events through May 2022. No patients were lost to follow-up. The primary efficacy outcome occurred in 22 of 641 in the rivaroxaban group and 19 of 643 in the placebo group (3.4% versus 3.0%; hazard ratio, 1.16 [95% CI, 0.63-2.15]; P=0.63). No patient in either group experienced critical-site or fatal bleeding. One patient receiving rivaroxaban had a major bleed. CONCLUSIONS: The study was terminated prematurely after enrollment of 32% of planned accrual because of recruitment challenges and lower-than-expected event rate. Rivaroxaban prescribed for 35 days in nonhospitalized patients with symptomatic COVID-19 at risk for thrombosis did not appear to reduce a composite end point of venous and arterial thrombotic events, hospitalization, and death. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT04508023.

Preventive effect and mechanism of Tibetan tea extract on thrombosis in arachidonic acid-induced zebrafish determined via RNA-seq transcriptome profiles.

Thrombosis is a key pathological event in cardiovascular diseases and is also the most important targeting process for their clinical management. In this study, arachidonic acid (AA) was used to induce thrombus formation in zebrafish larvae. Blood flow, red blood cell (RBCs) aggregation and cellular oxidative stress were measured to evaluate the antithrombotic effect of Tibetan tea (TT). Meanwhile, the potential molecular mechanism was further explored by transcriptome sequencing (RNA-seq). The results indicated that TT could significantly restore heart RBCs intensity of thrombotic zebrafish, whilst decreasing RBCs accumulation in the caudal vein. The transcriptome analysis revealed that the preventive effect of TT on thrombosis could be mostly attributed to changes in lipid metabolism related signaling pathways, such as fatty acid metabolism, glycerollipid metabolism, ECM-receptor interaction and steroid biosynthesis signaling pathway. This study demonstrated that Tibetan tea could alleviate thrombosis by reducing oxidative stress levels and regulating lipid metabolism.

Optimal Anticoagulation on TAVI Patients Based on Thrombotic and Bleeding Risk and the Challenge Beyond: A Systematic Review and Meta-Analysis.

Transcatheter Aortic Valve Replacement (TAVR) has been established as the treatment of choice for symptomatic aortic stenosis, while it is expanding in all risk-related group categories of patients, gaining gradually ground over the surgical approach. However, complications and adverse events are yet to be effectively limited and diminished with thrombotic and hemorrhagic events being rooted as a crucial topic of discussion. Favorable anticoagulation pharmacotherapy options are constantly being revised and tested, whilst guidelines are being modified to meet current clinical evidence. This review aims to systematically assess already existing guidelines on anticoagulation in post-TAVI patients and examine novel regimens for the specific use, like apixaban, rivaroxaban, and other anticoagulants, essentially constructing a holistic point of view on future progress on this matter. The added complexity brought by coagulation-affecting comorbidities such as atrial fibrillation, coronary artery disease, and more contributes to the direct association of the topic to the quality of healthcare as a public service. The literature was systematically searched to examine the effectiveness and safety of various anticoagulation treatments and cross-evaluate them based on the according category of patients that were assigned to. Clinical trials, observational studies and systematic reviews were included and, eventually, conclusive remarks and future considerations were developed and presented. In the category of patients without prior indication to anticoagulation, SAPT was proven safer and still effective, when antiplatelet therapies were compared, while a comparison of antiplatelet versus anticoagulation strategies noted the first one, with limited data, as the optimal one. Lastly, direct oral anticoagulants were shown to be safe substitutes for vitamin K antagonists for patients with prior indication to anticoagulation.

Effect of high-dose statin therapy on coagulation factors: Lowering of factor XI as a modifier of fibrin clot properties in coronary artery disease.

BACKGROUND: Multiple pleiotropic effects of statins include antithrombotic properties with formation of looser fibrin networks more susceptible to lysis. Recently, rosuvastatin 20 mg/d has been reported to decrease coagulation factors (F) VII, FVIII and FXI in venous thrombosis patients. OBJECTIVES: We investigated how high-dose statin therapy recommended in coronary artery disease (CAD) alters plasma levels of coagulation factors and if such changes might affect fibrin clot properties. METHODS: We studied 130 advanced CAD patients, who initially did not achieve the target low-density lipoprotein cholesterol (LDL-C). Before high-dose statin therapy (rosuvastatin 40 mg/d or atorvastatin 80 mg/d) and 6-12 months after its initiation, FII, FV, FVII, FVIII, FIX, FX, FXI and fibrinogen were assessed. We evaluated the impact of statin-induced alterations to the factors on plasma fibrin clot permeability (Ks) reflecting a fibrin pore size, and clot lysis time (CLT) reflecting fibrinolytic potential. RESULTS: At baseline LDL-C (median 3.2, interquartile range 2.7-3.7 mmol/L) was independently associated solely with FXI (ß = 0.58, P < 0.001). Median LDL-C reduction by 25% (P < 0.001) on high-dose statin treatment was accompanied by lowering of FVII, FVIII, and FXI (for all P < 0.001). On high-dose statin treatment, Ks (R = 0.65, P < 0.001) inversely associated with CRP (ß = -0.41, P < 0.001), LDL-C (ß = -0.26, P = 0.001), and FXI (ß = -0.18, P = 0.016). In turn, CLT (R = 0.45, P < 0.001) was positively associated with LDL-C (ß = 0.19, P = 0.043) and FXI (ß = 0.17, P = 0.049). CONCLUSIONS: High-dose statin therapy in CAD patients decreases FVII, FVIII, and FXI. The statin-induced reduction in FXI may contribute to less prothrombotic fibrin clot phenotype, indicating additional antithrombotic effect of high-dose statins.

Flavonoids as a therapeutical option for the treatment of thrombotic complications associated with COVID-19.

The SARS-CoV-2 outbreak has been one of the largest public health crises globally, while thrombotic complications have emerged as an important factor contributing to mortality. Therefore, compounds that regulate the processes involved in thrombosis could represent a dietary strategy to prevent thrombotic complications involved in COVID-19. In August 2022, various databases were consulted using the keywords "flavonoids", "antiplatelet", "anticoagulant", "fibrinolytic", and "nitric oxide". Studies conducted between 2019 and 2022 were chosen. Flavonoids, at concentrations mainly between 2 and 300 µM, are capable of regulating platelet aggregation, blood coagulation, fibrinolysis, and nitric oxide production due to their action on multiple receptors and enzymes. Most of the studies have been carried out through in vitro and in silico models, and limited studies have reported the in vivo and clinical effect of flavonoids. Currently, quercetin has been the only flavonoid evaluated clinically in patients with COVID-19 for its effect on D-dimer levels. Therefore, clinical studies in COVID-19 patients analyzing the effect on platelet, coagulant, fibrinolytic, and nitric oxide parameters are required. In addition, further high-quality studies that consider cytotoxic safety and bioavailability are required to firmly propose flavonoids as a treatment for the thrombotic complications implicated in COVID-19.

Trough anti-Xa activity after intermediate dose nadroparin for thrombosis prophylaxis in critically ill patients with COVID-19 and acute kidney injury.

Our objective was to assess the incidence of drug bioaccumulation in critically ill COVID-19 patients with AKI receiving intermediate dose nadroparin for thrombosis prophylaxis. We conducted a Prospective cohort study of critically ill COVID-19 patients. In patients on intermediate dose nadroparin (5700 IU once daily) we assessed the incidence of bioaccumulation (trough anti-Xa level > 0.2 IU/mL) stratified according to presence of AKI. We quantified this association using multilevel analyses. To assess robustness of our observations, we explored the association between AKI and anti-Xa activity in patients receiving high dose nadroparin (> 5700 IU). 108 patients received intermediate dose nadroparin, of whom 24 had AKI during 36 anti-Xa measurements. One patient with AKI (4.2% [95%CI 0.1-21%]) and 1 without (1.2% [95%CI 0.03-6.5%]) developed bioaccumulation (p = 0.39). Development of AKI was associated with a mean increase of 0.04 (95%CI 0.02-0.05) IU/ml anti-Xa activity. There was no statistically significant association between anti-Xa activity and AKI in 51 patients on high dose nadroparin. There were four major bleeding events, all in patients on high dose nadroparin. In conclusion, Bioaccumulation of an intermediate dose nadroparin did not occur to a significant extent in critically ill patients with COVID-19 complicated by AKI. Dose adjustment in AKI may be unnecessary.

Danshensu prevents thrombosis by inhibiting platelet activation via SIRT1/ROS/mtDNA pathways without increasing bleeding risk.

BACKGROUND: Coronary thrombosis and its correlated disorders are main healthcare problems globally. The therapeutic effects of current treatments involving antiplatelet drugs are not fully satisfactory. Danshensu (DSS) is an important monomer obtained from Salvia miltiorrhiza roots that have been widely employed for vascular diseases in medicinal practices. Nonetheless, the underlying mechanisms of DSS are not fully unraveled. PURPOSE: The objective of this study was to penetrate the antithrombotic and antiplatelet mechanisms of DSS. METHODS: Network pharmacology assay was used to forecast the cellular mechanisms of DSS for treating thrombosis. The work focused the impacts of DSS on platelet activation by analyzing aggregation and adhesion in vitro. Flow cytometry, western blotting, CM-H2DCFDA staining and mitochondrial function assays were performed to reveal the molecular mechanisms. The model of common carotid artery thrombus induced by ferric chloride was established. The wet weight of thrombus was measured, and the thrombosis was observed by hematoxylin and eosin (H&E) staining, in order to support the inhibitory effect of DSS on thrombosis. RESULTS: Data mining found the antithrombotic effect of DSS is related to platelet activation and the core target is silent information regulator 1 (SIRT1). We confirmed that DSS dose-dependently inhibited platelet activation in vitro. DSS was further demonstrated to induce the expression of SIRT1 and decreased reactive oxygen species (ROS) burden and thereby prevented mitochondrial dysfunction. Mitochondrial function tests further indicated that DSS prevented mitochondrial DNA (mtDNA) release, which induced activation of platelet in a dendritic cell specific intercellular-adhesion-molecule-3 grabbing non-integrin (DC-SIGN)-dependent manner. In carotid artery injury model induced by ferric chloride, DSS inhibited the development of carotid arterial thrombosis. More encouragingly, in tail bleeding time assay, DSS did not augment bleeding risk. CONCLUSION: These findings indicated that DSS effectively inhibited platelet activation by depressing the collection of ROS and the release of platelet mtDNA without arousing hemorrhage risk. DSS might represent a promising candidate drug for thrombosis and cardiovascular disease therapeutics.

Antithrombin supplementation for prevention of vascular thrombosis after pediatric liver transplantation.

AIMS: After liver transplantation (LT), synthesis of coagulation factors by the graft recovers faster for pro thrombotic than anti thrombotic factors, resulting in a potential pro thrombotic imbalance. We studied the thrombotic and hemorrhagic complications in our pediatric LT series, providing supplementation of fresh frozen plasma (FFP) and/or antithrombin (AT) in the prophylactic antithrombotic regimen. METHODS: This was a retrospective observational single center study. All isolated pediatric LTs performed between 1/11/2009 and 31/12/2019 (n = 181) were included. Postoperatively, in addition to low molecular weight heparin, 22 patients (12%) received FFP (10 ml/kg twice daily for 10 days), 27 patients (15%) were given FFP (reduced duration) and AT (50-100 IU/kg/day if AT activity remained <70%), and 132 (73%) received AT only. Complications, outcome, and coagulation profiles in postoperative days 0-10 were analyzed. RESULTS: In all three treatment groups, AT activity normalized by day 4 while prothrombin remained <70% of normal until day 9. Hepatic artery thrombosis (HAT), portal vein thrombosis (PVT), and hemorrhagic complications occurred in 2.8%, 3.3%, and 3.9% of LTs. One- and 5-year patient and graft survival were 88% (±2.4% Standard Error) and 84% (±2.5%), and 86% (±2.6%) and 84% (±2.7%), respectively, without difference between groups. HAT were associated with low AT on days 0 and 1, and PVT with low AT on day 0. CONCLUSIONS: Low antithrombin activity after LT was associated with postoperative thromboses. FFP and/or AT supplementation allowed early normalization of AT activity, while thrombotic or hemorrhagic complications were rare, suggesting efficient and safe management of post-LT coagulopathy.

Rivaroxaban Monotherapy vs Combination Therapy With Antiplatelets on Total Thrombotic and Bleeding Events in Atrial Fibrillation With Stable Coronary Artery Disease: A Post Hoc Secondary Analysis of the AFIRE Trial.

Importance: Appropriate regimens of antithrombotic therapy for patients with atrial fibrillation (AF) and coronary artery disease (CAD) have not yet been established. Objective: To compare the total number of thrombotic and/or bleeding events between rivaroxaban monotherapy and combined rivaroxaban and antiplatelet therapy in such patients. Design, Setting, and Participants: This was a post hoc secondary analysis of the Atrial Fibrillation and Ischemic Events With Rivaroxaban in Patients With Stable Coronary Artery Disease (AFIRE) open-label, randomized clinical trial. This multicenter analysis was conducted from February 23, 2015, to July 31, 2018. Patients with AF and stable CAD who had undergone percutaneous coronary intervention or coronary artery bypass grafting 1 or more years earlier or who had angiographically confirmed CAD not requiring revascularization were enrolled. Data were analyzed from September 1, 2020, to March 26, 2021. Interventions: Rivaroxaban monotherapy or combined rivaroxaban and antiplatelet therapy. Main Outcomes and Measures: The total incidence of thrombotic, bleeding, and fatal events was compared between the groups. Cox regression analyses were used to estimate the risk of subsequent events in the 2 groups, with the status of thrombotic or bleeding events that had occurred by the time of death used as a time-dependent variable. Results: A total of 2215 patients (mean [SD] age, 74 [8.2] years; 1751 men [79.1%]) were included in the modified intention-to-treat analysis. The total event rates for the rivaroxaban monotherapy group (1107 [50.0%]) and the combination-therapy group (1108 [50.0%]) were 12.2% (135 of 1107) and 19.2% (213 of 1108), respectively, during a median follow-up of 24.1 (IQR, 17.3-31.5) months. The mortality rate was 3.7% (41 of 1107) in the monotherapy group and 6.6% (73 of 1108) in the combination-therapy group. Rivaroxaban monotherapy was associated with a lower risk of total events compared with combination therapy (hazard ratio, 0.62; 95% CI, 0.48-0.80; P < .001). Monotherapy was an independent factor associated with a lower risk of subsequent events compared with combination therapy. The mortality risk after a bleeding event (monotherapy, 75% [6 of 8]; combination therapy, 62.1% [18 of 29]) was higher than that after a thrombotic event (monotherapy, 25% [2 of 8]; combination therapy, 37.9% [11 of 29]). Conclusions and Relevance: Rivaroxaban monotherapy was associated with lower risks of total thrombotic and/or bleeding events than combination therapy in patients with AF and stable CAD. Tapered antithrombotic therapy with a sole anticoagulant should be considered in these patients. Trial Registration: ClinicalTrials.gov Identifier: NCT02642419.

A case report of Budd-Chiari syndrome with cardiac complications and low SPO2 successfully managed by an integrated-approach

Budd-Chiari syndrome [BCS] is a rare, potentially life-threatening condition characterized by the triad of abdominal pain, ascites, and hepatomegaly (with or without jaundice). There will be an underlying disorder in most cases. The diagnosis, as well as management of the case, requires a multidisciplinary approach. The treatment should aim at reducing the presenting symptoms as well as removing the underlying pathology. Here we explain a case report of a 21-year-old male patient in the subacute stage of BCS with its complications and considered as a candidate for liver transplantation. His liver enzymes, PT/INR, D- dimer, and homocysteine values were above normal levels. The arterial oxygen saturation level was subnormal, and he was on supportive oxygen supplement. Inferior venacava [IVC] Doppler revealed a non-obstructive intrahepatic thrombus. The patient was treated with Homoeopathic medicine Arsenicum album and Arnica montana, given as an adjuvant to conventional treatment.

Prophylactic Rivaroxaban Therapy for Left Ventricular Thrombus After Anterior ST-Segment Elevation Myocardial Infarction.

OBJECTIVES: The aim of this study was to investigate the effects of rivaroxaban on left ventricle thromboprophylaxis in patients with anterior ST-segment elevation myocardial infarction (STEMI). BACKGROUND: Anterior STEMI is associated with an increased risk of left ventricular thrombus (LVT) formation. The contemporary role of prophylactic rivaroxaban therapy remains unclear. METHODS: We randomly assigned 279 patients with anterior STEMI who had undergone primary percutaneous coronary intervention to receive, in a 1:1 ratio, low-dose rivaroxaban (2.5 mg twice daily for 30 days) and dual antiplatelet therapy (DAPT) or only DAPT. The primary efficacy outcome was the LVT formation within 30 days. Net clinical adverse events were assessed at 30 days and 180 days, including all-cause mortality, LVT, systemic embolism, rehospitalization for cardiovascular events, and bleeding. RESULTS: The addition of low-dose rivaroxaban to DAPT reduced LVT formation within 30 days compared with only DAPT (0.7% vs 8.6%; HR: 0.08; 95% CI: 0.01-0.62; P = 0.015; P < 0.001 for superiority). Net clinical adverse events were lower within 30 days in the rivaroxaban group versus those in the only DAPT group and remained relatively low throughout the follow-up period. There were no significant differences in bleeding events between the 2 groups in 30 days and 180 days. However, 1 case of intracranial hemorrhage (major bleeding) occurred in the rivaroxaban group within 30 days. CONCLUSIONS: Our results supported that the short-duration addition of low-dose rivaroxaban to DAPT could prevent LVT formation in patients with anterior STEMI following primary percutaneous coronary intervention. A larger multiple-institution study is necessary to determine the generalizability.

Prevention of arterial and venous thrombotic events in symptomatic peripheral arterial disease patients after lower extremity revascularization in the VOYAGER PAD trial: Dual anticoagulant/antiplatelet regimen vs antiplatelet therapy alone.

BACKGROUND: Vascular disease burden after lower extremity revascularization (LER) comprises more than the first event, more vascular beds than the local arteries, and more than one clinical event type. OBJECTIVES: Assess total arterial and venous thrombotic burden after LER for symptomatic peripheral artery disease (PAD) and effect of low-dose anticoagulation added to low-dose antiplatelet therapy. PATIENTS/METHODS: VOYAGER PAD randomized 6564 symptomatic PAD patients undergoing LER to rivaroxaban 2.5 mg twice-daily or placebo on aspirin background. Marginal proportional-hazards models used to generate treatment hazard ratios and associated 95% CIs for first and total events; non-thrombotic deaths treated as competing terminal events. Incidence rates calculated as number of events per 100 patient-years follow-up. RESULTS: Over 2.5 years (median), first and total thrombotic event rates: 7.1 and 10.3 events/100 patient-years, respectively, in placebo group. Two-thirds (925/1372) of total thrombotic events (arterial 95%, venous 5%) were nonfatal first events. Nearly one-third of patients with first event had a second arterial or venous thrombotic event. Rivaroxaban plus aspirin reduced first and total arterial and venous thrombotic events to 5.4 and 7.9 events/100 patient-years, respectively, a reduction in total thrombotic events over aspirin of 23% (HR: 0.77, 95%CI: 0.67-0.89, p = .0005), preventing 6.1 total arterial and venous thrombotic events at 3 years. CONCLUSIONS: Assessing total arterial and venous thrombotic events, not just first events, provides more complete information about disease burden and absolute on-treatment impact. Following LER, judicious modulation of more than one coagulation pathway can provide broader benefit than intensifying inhibition of one hemostatic system component.

Purification and characterization of a novel thermostable anticoagulant protein from medicinal leech Whitmania pigra Whitman.

ETHNOPHARMACOLOGICAL RELEVANCE: The prevalence of cardiovascular disease (CVD) is increasing worldwide. Despite significant improvements in novel targeted treatment agents, natural products purified from medicinal animals with minimal side effects have attracted much attention. Several native proteins explored from suck-blood leeches, such as non-thermostable hirudin and its variants, revealed potent anticoagulant activity. Traditional Chinese medicine clinics have proved that non-suck-blood leech Whitmania pigra Whitman (W. pigra) also played notable roles in CVD treatments even after decoction. However, only a few natural proteins and peptides have been identified from the fresh material of this medicinal species. AIM OF THE STUDY: We aimed to purify and characterize thermostable anticoagulant proteins from W. pigra for further development of a therapeutic agent for thrombosis. MATERIALS AND METHODS: W. pigra crude extract was prepared by decoction in water. Anticoagulant proteins were purified by DEAE cellulose DE-52, Sephadex G-75, and reversed-phase liquid chromatography sequentially and analyzed by SDS-PAGE and LC-MS/MS for structural information. In addition, we conducted in vitro anticoagulant experiments, including plasma recalcification time (PRT) assay, fibrinolytic assay, activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT), fibrinogen (Fib) assay, and cell viability assays. Furthermore, a carrageenan-induced chronic thromboembolism model was employed in ICR mice, and four coagulation factors (APTT, PT, TT, and Fib) activities were determined after intragastric administration. RESULTS: The anticoagulant protein WP-77 has a relative molecular weight of ca. 20.8 kDa. It was effective over a broad temperature range from 20 °C to 100 °C and a pH 2-8 condition. The anticoagulant activity of WP-77 was retained after incubation with pepsin but was greatly inhibited by trypsin (P < 0.01). It significantly prolonged APTT and TT (P < 0.05) but had little effect on PT and Fib in vitro. Furthermore, WP-77 of a low concentration resulted in the recovery of injured EA.hy926 by thrombin. The protein also significantly prolonged APTT and TT (P < 0.01) and inhibited thrombus formation in carrageenan-induced thrombosis mice, demonstrating its antithrombotic effect in vivo. CONCLUSION: Our results suggest that WP-77 from W. pigra plays a distinct role in treating thrombotic diseases, and it is an essential substance of anticoagulant activity of non-suck-blood medicinal leeches. This thermostable anticoagulant protein could be a promising candidate for the development of clinical antithrombosis medicines.