Anticoagulation Management Post Pulmonary Embolism.

Pulmonary embolus (PE) carries a significant impending morbidity and mortality, especially in intermediate and high-risk patients, and the choice of initial anticoagulation that allows for therapeutic adjustment or manipulation is important. The preferred choice of anticoagulation management includes direct oral anticoagulants. Vitamin K antagonists and low-molecular-weight heparin are preferred in special populations or selected patients such as breastfeeding mothers, those with end-stage renal disease, or obese patients, among others. This article reviews the primary and longer-term considerations for anticoagulation management in patients with PE and highlights special patient populations and risk factor considerations.

[Is low-dose anticoagulation a therapeutic option for patients at high risk of bleeding with high-risk pulmonary thromboembolism].

This issue of Chinese Journal of Tuberculosis and Respiratory Diseases published an interesting case illustrating the identification, treatment, and post-treatment management of a high-risk pulmonary thromboembolism (PTE) that occurred during surgery. It was a high-risk case of PTE, but during treatment, the risk stratification changed to medium-high risk. We should dynamically assess risk stratification and develop diagnosis and treatment plans based on changes in the patient's condition. At the same time, there was a high risk of bleeding in this patient. We should try to decrease the risk of bleeding as much as possible, consider all the conditions that can be applied at that time and on a local level, and devise a safe and effective treatment plan. The socio-economic status of patients may have an impact on how the final diagnosis and treatment plan are implemented. We need to communicate fully with patients, consider comprehensively, and prepare contingency plans to ensure patients' life safety to the greatest extent possible.

[Successful treatment of high-risk pulmonary embolism with low-dose anticoagulation: a case report].

Reperfusion is considered as the cornerstone of the treatment of high-risk pulmonary embolism (PE). However, when thrombolysis is contraindicated and surgery or interventional therapy is not available, the treatment of high-risk PE becomes very difficult. To our knowledge, there are no reports of successful treatment of high-risk PE with low-dose anticoagulation. On November 30, 2021, a 56-year-old male patient with subarachnoid hemorrhage was admitted to the emergency department of the First Affiliated Hospital of Chongqing Medical University. On the second day of admission, the patient suddenly went into shock during aneurysm clipping. After implementing D-dimer, markers of myocardial injury, echocardiography and computed tomography pulmonary angiography, a high-risk PE was diagnosed. Due to the contraindication of thrombolysis and the refusal of endovascular treatment, he was eventually cured with low-dose anticoagulation combined with vasopressors.

Direct Oral Anticoagulants in Chronic Thromboembolic Pulmonary Hypertension: First Meta-Analysis of Prospective Studies.

Direct oral anticoagulants (DOACs) are becoming increasingly popular clinically, but their safety and effectiveness profile in patients with chronic thromboembolic pulmonary hypertension (CTEPH) is not well-established. Literature from the PubMed and EMBASE databases was systematically screened up to February 2024 to identify relevant studies on the use of DOACs in CTEPH patients. The bias risk of RCTs was assessed using the Cochrane Risk of Bias Tool 2.0. The quality of observational prospective cohorts was assessed using the Newcastle-Ottawa Scale tool. Data pooled from different studies were analyzed. Results from 4 studies were gathered, including 2 randomized controlled trials and 2 prospective cohorts, with a total of 2038 patients, of which 751 were on DOACs and 1287 were on vitamin K antagonists (VKAs). Similar rates of all-cause mortality (3.33% vs 3.33%, RD = -0.01%, 95% CI [-0.02%, 0.00%], P = .17), VTE recurrence (1.46% vs 2.12%, RD = -0.00%, 95% CI [-0.01%, 0.01%], P = .92) were observed. DOACs were associated with a nonsignificant reduction in bleeding events including major bleeding (2.22% vs 3.71%, RD = -0.01%, 95% CI [-0.04%, 0.01%], P = .30), any bleeding (5.33% vs 9.94%, RD = -0.03%, 95% CI [-0.07%, 0.01%], P = .10), and minor bleeding (4.17% vs 13.3%, RD = -0.06%, 95% CI [-0.23%, 0.10%], P = .45). Data pooled from existing perspective trials suggests the use of DOACs in CTEPH patients as an effective and safe alternative to VKAs.

Pulmonary Thromboembolism following Russell's Viper Bites.

Snakebite envenoming and its resulting complications are serious threats to the health of vulnerable people living in rural areas of developing countries. The knowledge of the heterogeneity of symptoms associated with snakebite envenoming and their management strategies is vital to treat such life-threatening complications to save lives. Russell's viper envenomation induces a diverse range of clinical manifestations from commonly recognised haemotoxic and local effects to several rare conditions that are often not reported. The lack of awareness about these unusual manifestations can affect prompt diagnosis, appropriate therapeutic approaches, and positive outcomes for patients. Here, we report pulmonary thromboembolism that developed in three patients following Russell's viper envenomation and demonstrate their common clinical features and diagnostic and therapeutic approaches used. All patients showed clinical signs of local (oedema) and systemic (blood coagulation disturbances) envenomation, which were treated using polyvalent antivenom. They exhibited elevated heart rates, breathlessness, and reduced oxygen saturation, which are non-specific but core parameters in the diagnosis of pulmonary embolism. The recognition of pulmonary embolism was also achieved by an electrocardiogram, which showed sinus tachycardia and computed tomography and echocardiogram scans further confirmed this condition. Anti-coagulant treatment using low-molecular-weight heparin offered clinical benefits in these patients. In summary, this report reinforces the broad spectrum of previously unreported consequences of Russell's viper envenomation. The constant updating of healthcare professionals and the dissemination of major lessons learned in the clinical management of snakebite envenoming through scientific documentation and educational programs are necessary to mitigate the adverse impacts of venomous snakebites in vulnerable communities.

Sildenafil improves hemodynamic changes caused by acute pulmonary embolism by inhibiting Rho kinase activity.

OBJECTIVE: This study examined the effects of sildenafil on acute pulmonary embolism (APE) using a rat model. METHODS: Sprague-Dawley rats were randomly divided into the sham, pulmonary thromboembolism (PTE), and sildenafil groups. The sham and PTE groups received normal saline once daily via gavage for 14 consecutive days, whereas the sildenafil group received sildenafil (0.5 mg/kg/day) once daily via gavage for 14 consecutive days. Autologous emboli were prepared from blood samples collected from the left femoral artery of rats in each group on day 13, and autologous emboli were injected into the jugular vein cannula of rats in the PTE and sildenafil groups on day 14. Sham-treated rats received the same volume of saline. Right systolic ventricular pressure (RVSP) and mean pulmonary arterial pressure (MPAP) were used to assess pulmonary embolism, and western blotting and enzyme-linked immunosorbent assay were used to detect relevant markers. RESULTS: The Rho kinase signaling pathway was significantly activated in rats with APE, and sildenafil significantly inhibited this activation. CONCLUSIONS: Sildenafil protected against APE through inhibiting Rho kinase activity, thereby reducing pulmonary vasoconstriction and decreasing elevated pulmonary arterial pressure. These findings might provide new ideas for the clinical treatment of acute pulmonary thromboembolism.

Curcumin alleviates myocardial inflammation, apoptosis, and oxidative stress induced by acute pulmonary embolism by regulating microRNA-145-5P/insulin receptor substrate 1 axis.

The treatment of patients with acute pulmonary embolism (APE) is extremely challenging due to the complex clinical presentation and prognosis of APE related to the patient's hemodynamic status and insufficient arterial blood flow and right ventricular overload. Protective efficacy against cardiovascular diseases of curcumin, a common natural polyphenolic compound, which has antithrombotic properties and reduces platelet accumulation in the circulation by inhibiting thromboxane synthesis has been demonstrated. However, the direct effect of curcumin on APE has rarely been studied. Therefore, the present study aimed to investigate the therapeutic potential of curcumin in APE and associated myocardial injury to provide new insights into curcumin as a promising competitive new target for the treatment of APE. A suspension of 12 mg/kg microspheres was injected intravenously into rats. An APE rat model was built. Before modeling, intragastric 100 mg/kg curcumin was given, and/or lentiviral plasmid vector targeting microRNA-145-5p or insulin receptor substrate 1 (IRS1) was injected. Pulmonary artery pressure was measured to assess right ventricular systolic pressure (RVSP). Hematoxylin and eosin (H&E) staining was performed on liver tissues and myocardial tissues of APE rats. TUNEL (terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling) staining and immunohistochemical (IHC) staining were conducted to measure apoptosis and CyPA-CD147 expression in the myocardium, respectively. Inflammatory indices interleukin-1beta (IL-1ß), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) were measured by ELISA in cardiac tissues. RT-qPCR and Western blot were performed to determine the expression levels of related genes. In addition, by dual luciferase reporter assay and RIP assay, the relationship between microRNA-145-5p and insulin receptor substrate 1 (IRS1) was confirmed. In results: curcumin improved APE-induced myocardial injury, reduced myocardial tissue edema, and thrombus volume. It attenuated APE-induced myocardial inflammation and apoptosis, as well as reduced lung injury and pulmonary artery pressure. Curcumin promoted microRNA-145-5p expression in APE rat myocardium. MicroRNA-145-5p overexpression protected against APE-induced myocardial injury, and microRNA-145-5p silencing abolished the beneficial effects of curcumin in APE-induced myocardial injury. IRS1 was targeted by microRNA-145-5p. IRS1 silencing attenuated APE-induced myocardial injury, and enhanced therapeutic effect of curcumin on myocardial injury in APE rats. In conclusion, curcumin alleviates myocardial inflammation, apoptosis, and oxidative stress induced by APE by regulating microRNA-145-5p/IRS1 axis.

Angio-Jet Thrombolysis for Traumatic Inferior Vena Cava Thrombosis; Case Report and Review of Literature.

Background: Inferior vena cava thrombosis (IVC-Th) is a rare clinical entity after blunt abdominal trauma. It has both diagnostic and therapeutic dilemmas. Pulmonary embolism is the most dreadful complication and the leading cause of mortality after IVC-Th. Therefore, accurate prompt diagnosis is crucial. Objective: The aim of this article was to present a case of IVC-Th in a young male patient who had a blunt traumatic abdominal injury after a motor vehicle accident. Case presentation: The patient was brought to emergency department and was successfully managed by angio-jet thrombolysis. He developed a transient contrast nephropathy that was recovered after continuous renal replacement therapy. Several management options have been proposed in the literature, including conservative, endovascular and operative management. Conclusion: Angio-jet is a recent promising technique for managing of venous thrombosis. However, its use in cases of IVC-Th is not extensively discussed in the literature.

Biomarkers Profile in Provoked Versus Unprovoked Deep Venous Thrombosis.

Venous thromboembolism (VTE), including deep venous thrombosis (DVT) and pulmonary embolism (PE), represents a substantial healthcare challenge. Provoked and unprovoked DVT cases carry distinct risks and treatment considerations. Recognizing the limitations of this classification, molecular markers may enhance diagnostic precision and guide anticoagulation therapy duration relying on patient history and risk factors. This preliminary, open-label, prospective cohort study was conducted including 15 patients (10 provoked DVT and 5 unprovoked DVT) and a control group of healthy plasmatic subjects. Plasma levels of 9 biomarkers were measured at diagnosis (baseline, day 0, and D0) and after 30 days (day 30-D30). Patient demographics, clinical data, and biomarker concentrations were analyzed. Serum concentrations of D-dimer, von Willebrand factor, C-reactive protein, and Anti-Xa were elevated in DVT groups at D0 compared to controls. No significant differences were observed between the provoked and unprovoked groups on the day of diagnosis and 30 days later. Over 30 days, the provoked group exhibited significant biomarker changes related to temporal assessment. No significant differences were noted in the biomarker profile between provoked and unprovoked DVT groups. This study is indicative of the concept of individualized thrombosis assessment and subsequent treatment for VTE. Larger cohorts are warranted to validate these findings and further define the most appropriate use of the molecular markers.

A Case Report of Pulmonary Embolectomy Under Cardiopulmonary Bypass in a Patient with Intracranial Hemorrhage and History of Heparin-Induced Thrombocytopenia.

Pulmonary embolism is a common complication after intracranial hemorrhage. As thrombolysis is contraindicated in this situation, surgical pulmonary embolectomy may be indicated in case of high-risk pulmonary embolism but requires transient anticoagulation with heparin during cardiopulmonary bypass. We report the case of a patient with a history of heparin-induced thrombocytopenia who presented with a high-risk pulmonary embolism 10 days after the spontaneous onset of a voluminous intracerebral hematoma. Despite high doses of heparin required to run the cardiopulmonary bypass and subsequent anticoagulation by danaparoid sodium, the brain hematoma remained stable and the patient was discharged without complications 30 days after surgery.

Structured benefit-risk assessment for enoxaparin, in the context of its label extension, for the extended treatment of deep vein thrombosis and pulmonary embolism, and prevention of its recurrence in patients with active cancer.

PURPOSE: Guidelines recommend low-molecular-weight heparins (LMWHs) for patients with cancer-associated thrombosis. However, until recently, only dalteparin and tinzaparin were approved in the European Economic Area (EEA) for these patients. This study compares the benefit-risk profile of enoxaparin with dalteparin and tinzaparin for the extended treatment of deep vein thrombosis (DVT) and pulmonary embolism (PE), and prevention of recurrence in adult patients with active cancer. METHODS: A semi-quantitative structured benefit-risk assessment was conducted for the label-extension application of enoxaparin based on the benefit-risk action team descriptive framework: define decision context; determine key benefit and risk outcomes; identify data sources; extract data; interpret results. RESULTS: The key benefits were defined as reduced all-cause mortality and venous thromboembolism (VTE) recurrence (including symptomatic DVT, fatal PE or non-fatal PE); the key risks were major and non-major bleeding of clinical significance, and heparin-induced thrombocytopenia (HIT). Enoxaparin demonstrated comparable effects for the reduction of VTE recurrence and all-cause mortality versus other EEA-approved LMWHs (dalteparin, tinzaparin). There was no evidence of a significant difference between enoxaparin and the comparator groups with regard to incidence of major and non-major bleeding. The data on HIT were too limited to assess the difference between the two groups. CONCLUSIONS: The assessment demonstrated a favourable benefit-risk profile for enoxaparin similar to that of other EEA-approved LMWHs for the treatment of DVT and PE and the prevention of recurrence in patients with active cancer and thus supported the label-extension approval.

Acute pulmonary embolism in cancer patients admitted to intensive care unit: Impact of anticoagulant treatment on 90-day mortality and risk factors, results of a multicentre retrospective study.

BACKGROUND: Acute pulmonary embolism (PE) is a life-threatening situation in cancer patients. In this situation, anticoagulant therapy is complex to administer due to the risk of bleeding. Only few studies have been conducted when these patients are admitted to the intensive care unit (ICU). The aim of this study was to assess the association between anticoagulation strategies as well as other factors with 90-day mortality in patients with cancer and PE admitted to ICU. Major bleeding was also evaluated according to the type of anticoagulation. METHODS: Retrospective study carried out in 4 ICUs in France over a 12-year period (2009-2021). All patients with cancer and PE were included. An overlap propensity score weighting analysis was performed in the subgroup of patients treated with either unfractionated heparins (UFH) alone or low-molecular-weight heparins (LMWH) alone on 90-day mortality and major bleeding. RESULTS: A total of 218 consecutive cancer patients admitted to ICU and presenting PE were included. The 90-day mortality rate was 42 % for the global cohort. After propensity score analysis in the subgroup of patients treated with either "UFH alone" (n = 80) or "LMWH alone" (n = 71), the 90-day mortality was similar in patients treated with UFH alone (42.6 %) vs LMWH alone (39.9 %): OR = 1.124, CI 95 % [0.571-2.214], p = 0.750. There was a significant increased toward major bleeding rates in the "UFH alone" group (25.5 %) as compared to "LMWH alone" group (11.5 %), p = 0.04. CONCLUSION: In 218 patients admitted to ICU and presenting PE, the 90-day mortality rate was 42 %. Treatment with UFH alone was associated with a mortality comparable to treatment with LMWH alone but it appeared to be more prone to major bleeding.

Impact of chronic oral glucocorticoid treatment on mortality in patients with COVID-19: analysis of a population-based cohort.

OBJECTIVES: While glucocorticoid (GC) treatment initiated for COVID-19 reduces mortality, it is unclear whether GC treatment prior to COVID-19 affects mortality. Long-term GC use raises infection and thromboembolic risks. We investigated if patients with oral GC use prior to COVID-19 had increased mortality overall and by selected causes. DESIGN: Population-based observational cohort study. SETTINGS: Population-based register data in Sweden. PARTICIPANTS: All patients infected with COVID-19 in Sweden from January 2020 to November 2021 (n=1 200 153). OUTCOME MEASURES: Any prior oral GC use was defined as ≥1 GC prescription during 12 months before index. High exposure was defined as ≥2 GC prescriptions with a cumulative prednisolone dose ≥750 mg or equivalent during 6 months before index. GC users were compared with COVID-19 patients who had not received GCs within 12 months before index. We used Cox proportional hazard models and 1:2 propensity score matching to estimate HRs and 95% CIs, controlling for the same confounders in all analyses. RESULTS: 3378 deaths occurred in subjects with any prior GC exposure (n=48 806; 6.9%) and 14 850 among non-exposed (n=1 151 347; 1.3%). Both high (HR 1.98, 95% CI 1.87 to 2.09) and any exposure (1.58, 1.52 to 1.65) to GCs were associated with overall death. Deaths from pulmonary embolism, sepsis and COVID-19 were associated with high GC exposure and, similarly but weaker, with any exposure. High exposure to GCs was associated with increased deaths caused by stroke and myocardial infarction. CONCLUSION: Patients on oral GC treatment prior to COVID-19 have increased mortality, particularly from pulmonary embolism, sepsis and COVID-19.

Therapeutic efficacy of tranexamic acid on traumatic brain injury: a systematic review and meta-analysis.

OBJECTIVE: Tranexamic acid (TXA) demonstrates therapeutic efficacy in the management of traumatic brain injury (TBI). The objective of this systematic review and meta-analysis was to evaluate the safety and effectiveness of TXA in patients with TBI. METHODS: The databases, namely PubMed, Embase, Web of Science, and Cochrane Library databases, were systematically searched to retrieve randomized controlled trials (RCTs) investigating the efficacy of TXA for TBI from January 2000 to November 2023. RESULTS: The present meta-analysis incorporates ten RCTs. Compared to the placebo group, administration of TXA in patients with TBI resulted in a significant reduction in mortality (P = 0.05), hemorrhage growth (P = 0.03), and volume of hemorrhage growth (P = 0.003). However, no significant impact was observed on neurosurgery outcomes (P = 0.25), seizure occurrence (P = 0.78), or pulmonary embolism incidence (P = 0.52). CONCLUSION: The administration of TXA is significantly associated with reduced mortality and hemorrhage growth in patients suffering from TBI, while the need of neurosurgery, seizures, and incidence of pulmonary embolism remains comparable to that observed with placebo.

Ultrasound-Assisted Catheter-Directed Thrombolysis for the Management of Pulmonary Embolism: A Single Center Experience in a Community Hospital.

Current guidelines recommend anticoagulation alone for low-risk pulmonary embolism (PE) with the addition of systemic thrombolysis for high-risk PE. However, treatment recommendations for intermediate-risk PE are not well-defined. Due to bleeding risks associated with systemic thrombolysis, ultrasound-assisted catheter-directed thrombolysis (USAT) has evolved as a promising treatment modality. USAT is thought to decrease the rate of major bleeding by using localized delivery with lower thrombolytic dosages. Currently, there is little guidance on the implementation of USAT in the real-world clinical setting. This study was designed to evaluate our experience with USAT at this single community hospital with a newly initiated Pulmonary Embolism Response Team (PERT). All patients identified by the PERT with an acute PE diagnosed by a computed tomography (CT) scan from January 2021 to January 2023 were included. During the study period, there were 89 PERT activations with 40 patients (1 high-risk and 37 intermediate-risk PE) receiving USAT with alteplase administered at a fixed rate of 1 mg/h per catheter for 6 h. The primary efficacy outcome was the change in Pulmonary Embolism Severity Index (PESI) score within 48 h after USAT. The primary safety outcome was major bleeding within 72 h. The mean age was 57.4 ± 17.4 years and 50% (n = 20) were male, 17.5% (n = 7) had active malignancy, and 20% (n = 8) had a history of prior deep vein thrombosis (DVT) or PE. The mean PESI score decreased from baseline to 48 h post-USAT (84.7 vs 74.9; p = 0.025) and there were no major bleeding events. The overall hospital length of stay was 7.5 ± 9.8 days and ICU length of stay was 2.2 ± 2.8 days. This study outlined our experience at this single community hospital which resulted in an improvement in PESI scores and no major bleeding events observed.

Evaluating pharmacological THRomboprophylaxis in Individuals undergoing superficial endoVEnous treatment across NHS and private clinics in the UK: a multi-centre, assessor-blind, randomised controlled trial-THRIVE trial.

INTRODUCTION: Endovenous therapy is the first choice management for symptomatic varicose veins in NICE guidelines, with 56-70 000 procedures performed annually in the UK. Venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), is a known complication of endovenous therapy, occurring at a rate of up to 3.4%. Despite 73% of UK practitioners administering pharmacological thromboprophylaxis to reduce VTE, no high-quality evidence supporting this practice exists. Pharmacological thromboprophylaxis may have clinical and cost benefit in preventing VTE; however, further evidence is needed. This study aims to establish whether when endovenous therapy is undertaken: a single dose or course of pharmacological thromboprophylaxis alters the risk of VTE; pharmacological thromboprophylaxis is associated with an increased rate of bleeding events; pharmacological prophylaxis is cost effective. METHODS AND ANALYSIS: A multi-centre, assessor-blind, randomised controlled trial (RCT) will recruit 6660 participants from 40 NHS and private sites across the UK. Participants will be randomised to intervention (single dose or extended course of pharmacological thromboprophylaxis plus compression) or control (compression alone). Participants will undergo a lower limb venous duplex ultrasound scan at 21-28 days post-procedure to identify asymptomatic DVT. The duplex scan will be conducted locally by blinded assessors. Participants will be contacted remotely for follow-up at 7 days and 90 days post-procedure. The primary outcome is imaging-confirmed lower limb DVT with or without symptoms or PE with symptoms within 90 days of treatment. The main analysis will be according to the intention-to-treat principle and will compare the rates of VTE at 90 days, using a repeated measures analysis of variance, adjusting for any pre-specified strongly prognostic baseline covariates using a mixed effects logistic regression. ETHICS AND DISSEMINATION: Ethical approval was granted by Brent Research Ethics Committee (22/LO/0261). Results will be disseminated in a peer-reviewed journal and presented at national and international conferences. TRIAL REGISTRATION NUMBER: ISRCTN18501431.

Kidney Transplant Recipient With Cerebral Paradoxical Embolism Following Recurrent Idiopathic Deep Vein Thrombosis and Pulmonary Embolism: Case Report and Review of the Literature.

Paradoxical embolism occurs when a thrombus crosses an intracardiac defect into the systemic circulation. Here, we present the case of a 35-yearold male kidney transplant recipient with a cerebral paradoxical embolism associated with a spontaneous venous thromboembolism. This patient had recurrent deep venous thrombosis and showering emboli to the lung and paradoxically to the brain through patent foramen ovale, and we treated him successfully. The role of bubble echocardiography was essential in diagnosis to avoid contrast-induced nephropathy. This is the first successfully managed case of a kidney transplant recipient with recurrent idiopathic deep vein thrombosis, pulmonary embolism, and cerebral paradoxical embolism. Bubble echocardiography was an excellent alternative to contrast angiography to avoid nephrotoxicity. Vitamin K antagonists are superior to direct oral anticoagulants, especially among nonadherent/noncompliant patients.

Eugenol Suppresses Platelet Activation and Mitigates Pulmonary Thromboembolism in Humans and Murine Models.

Platelets assume a pivotal role in the pathogenesis of cardiovascular diseases (CVDs), emphasizing their significance in disease progression. Consequently, addressing CVDs necessitates a targeted approach focused on mitigating platelet activation. Eugenol, predominantly derived from clove oil, is recognized for its antibacterial, anticancer, and anti-inflammatory properties, rendering it a valuable medicinal agent. This investigation delves into the intricate mechanisms through which eugenol influences human platelets. At a low concentration of 2 µM, eugenol demonstrates inhibition of collagen and arachidonic acid (AA)-induced platelet aggregation. Notably, thrombin and U46619 remain unaffected by eugenol. Its modulatory effects extend to ATP release, P-selectin expression, and intracellular calcium levels ([Ca2+]i). Eugenol significantly inhibits various signaling cascades, including phospholipase Cγ2 (PLCγ2)/protein kinase C (PKC), phosphoinositide 3-kinase/Akt/glycogen synthase kinase-3ß, mitogen-activated protein kinases, and cytosolic phospholipase A2 (cPLA2)/thromboxane A2 (TxA2) formation induced by collagen. Eugenol selectively inhibited cPLA2/TxA2 phosphorylation induced by AA, not affecting p38 MAPK. In ADP-treated mice, eugenol reduced occluded lung vessels by platelet thrombi without extending bleeding time. In conclusion, eugenol exerts a potent inhibitory effect on platelet activation, achieved through the inhibition of the PLCγ2-PKC and cPLA2-TxA2 cascade, consequently suppressing platelet aggregation. These findings underscore the potential therapeutic applications of eugenol in CVDs.