Venous thromboembolism (VTE) is a leading cause of preventable hospital-acquired morbidity and mortality. Despite the availability of effective prophylaxis, its application in clinical practice remains inconsistent, often due to uncertainty in risk stratification. This review evaluates the validity and implementation of VTE risk assessment models (RAMs) in medical inpatients. Seven widely used RAMs, Caprini, Padua, IMPROVE, IMPROVEDD, Wells, Geneva, and Kucher e-alert, are critically examined alongside emerging digital and biomarker-enhanced tools. The Padua and IMPROVE scores show consistent reliability across various medical populations, while the Caprini RAM remains the most accurate in surgical contexts. The Wells deep vein thrombosis (DVT) and revised Geneva scores are preferred for diagnosing suspected thrombosis and pulmonary embolism, respectively. Electronic alerts, such as the Kucher and Woller models, have shown promise in increasing prophylaxis adherence and reducing symptomatic VTE events. Nonetheless, challenges like limited external validation, gaps in clinician training, and inconsistent local protocols hinder their real-world application. Future research should recalibrate RAMs for underrepresented groups, incorporate biomarkers and mobility data, and create user-friendly AI tools that can optimize the balance between thrombosis and bleeding risks. The adoption of validated, user-friendly RAMs is essential for improving thromboprophylaxis, enhancing patient safety, and reducing the burden of hospital-associated VTE.

Direct Oral Anticoagulants (DOACs) have revolutionized the treatment of thromboembolic disorders, offering targeted, effective, and safer alternatives to traditional anticoagulants like heparins and vitamin K antagonists (VKAs). Despite their benefits, DOACs have drawbacks, including an increased risk of gastrointestinal bleeding and unsuitability for patients with mechanical heart valves. Recent research has highlighted Factor XI (FXI) as a promising anticoagulation target due to its significant role in pathological thrombosis and minor involvement in normal hemostasis. Abelacimab, an antibody that inhibits FXI, has shown potential in transforming anticoagulation therapy by sparing hemostasis. This review provides a comprehensive analysis of abelacimab, examining its clinical pharmacology and its pharmacokinetic and pharmacodynamic properties. It scrutinizes abelacimab's safety profile and key monitoring parameters. The current evidence supporting its use and potential future research strengthening its position in anticoagulant therapy is also discussed. The objective is to enhance understanding and contribute to discussions around developing safer anticoagulants, particularly for patients at risk for thrombosis.

Background: Antiphospholipid Syndrome (APS) is an autoimmune condition that increases thrombosis risk. Although Vitamin K antagonists (VKA) are standard treatment, interest in direct oral anticoagulants (DOAC) has grown. Recent studies evaluated DOAC across all APS subgroups. This review updates our understanding of DOAC's efficacy and safety compared to VKA in preventing thrombotic complications, integrating new findings into the literature. Methods: A systematic review across PubMed/Medline, Embase, and Cochrane was conducted in accordance with PRISMA guidelines. The quality of randomized controlled trials (RCTs) and cohort studies was assessed using the Cochrane Risk of Bias tool and the Newcastle-Ottawa Scale, respectively. Meta-analysis calculated odds ratios (OR) using the random effect model for arterial and venous thrombotic and bleeding outcomes Results: Of a total of 2385 records identified, the meta-analysis included 11 studies, comprising 5 RCTs and 7 observational studies, with a combined total of 1813 participants. The analysis revealed no significant difference in the odds of venous thromboembolism (VTE) between DOAC and VKA (OR = 0.80; 95% CI 0.41-1.56). However, a significant increase in thromboembolism recurrence was noted in triple-positive APS patients using DOAC compared to VKA (OR = 3.62; 95% CI 1.10-11.98). The risk of major bleeding was similar between DOAC and VKA (OR = 1.02; 95% CI 0.62-1.68). Additionally, the pooled analysis indicated a higher risk of arterial thrombosis with DOAC (OR = 6.21; 95% CI 2.06-18.76). Conclusion: Overall, findings suggest DOAC are comparably safe but increase the risk of arterial thrombosis and VTE in triple-positive APS, favoring warfarin for prophylaxis.

Background: Nutritional deficiency anemias—including iron, vitamin B12, and folate deficiencies—are common worldwide and are increasingly recognized as potential contributors to venous thromboembolism (VTE). Mechanistic and epidemiologic data suggest that anemia may promote thrombosis through hypoxia, endothelial activation, reactive thrombocytosis, and hyperhomocysteinemia. However, a focused synthesis of clinical and genetic evidence specifically linking nutritional deficiency anemia to VTE has been lacking. Methods: We conducted a systematic search of PubMed and the Cochrane Library from inception to 30 September 2025 to identify studies assessing nutritional deficiency anemia in relation to VTE outcomes. Eligible studies included observational designs, case reports, case series, and Mendelian randomization (MR) analyses. Quality assessment followed the Newcastle–Ottawa Scale (NOS), Joanna Briggs Institute (JBI) checklists, and ROB-MR. The review was registered in PROSPERO (CRD420251235479). Results: Seven studies met the inclusion criteria. Observational analytical studies consistently showed that anemia was associated with adverse VTE-related outcomes. Lower hemoglobin predicted higher short-term mortality in acute pulmonary embolism (HR 1.16 per 1 g/dL decrease), increased symptomatic VTE among hospitalized patients (RR 1.94), and greater long-term bleeding and mortality risk in VTE cohorts (HRs 1.41–2.89). Iron-deficiency anemia increased the odds of VTE in population-based data (OR 1.43), and case reports described unprovoked DVT in young adults with moderate to severe anemia. The MR study indicated a potential causal association between anemia traits and thrombosis at unusual anatomical sites (OR 1.446). No study demonstrated a significant association with recurrent VTE. Most analytical studies were rated as good–high quality. Conclusion: Across multiple study designs, anemia—particularly iron-deficiency anemia and low baseline hemoglobin—appears to be an underrecognized factor associated with elevated VTE risk and adverse VTE-related outcomes. However, direct evidence for vitamin B12- and folate-deficiency anemia remains limited, and further well-designed prospective studies are required to confirm causality and clarify the contribution of specific nutritional deficiency subtypes, as well as to support integration of anemia assessment into VTE risk models.

Background: Tumor thrombus (TT), defined as intravascular extension of malignant tissue, is a distinct manifestation of cancer-associated thrombosis driven by malignant vascular invasion rather than fibrin-rich clot. Despite limited evidence, anticoagulant therapy is frequently prescribed empirically. This systematic review synthesized available data on the effectiveness and safety of anticoagulation in adults with solid tumor–associated TT. Methods: A PRISMA (2020) compliant systematic review (PROSPERO-registered) was conducted using PubMed/MEDLINE, Embase, and CENTRAL through September 2025. Eligible studies included adults with solid tumor–associated TT who received anticoagulation and reported thrombus response, thromboembolic recurrence, survival, or bleeding outcomes. Results were synthesized narratively in accordance with SWiM guidance. Risk of bias was assessed using the Newcastle–Ottawa Scale and the Joanna Briggs Institute tools, and the certainty of evidence was assessed using the GRADE approach. Results: Eight studies met the inclusion criteria, comprising three retrospective cohort studies and five case reports. Anticoagulants evaluated included low-molecular-weight heparin, vitamin K antagonists, direct oral anticoagulants, unfractionated heparin, and parenteral direct thrombin inhibitors. Across all studies, anticoagulation alone was not associated with radiographic regression of TT. Apparent thrombus resolution occurred exclusively following tumor-directed or mechanical interventions, such as surgical thrombectomy or percutaneous aspiration, and could not be attributed to anticoagulation alone. Evidence for a reduction in thromboembolic recurrence was limited, heterogeneous, and inconsistently adjudicated as bland thrombosis versus malignant embolic disease. No survival benefit attributable to anticoagulation was demonstrated. In contrast, anticoagulant therapy was associated with a clinically meaningful risk of major bleeding, particularly among patients with renal cell carcinoma–associated TT. Overall certainty of evidence ranged from very low to moderate. Conclusion: Current evidence does not demonstrate a consistent benefit of routine anticoagulation for isolated TT. Anticoagulation may be appropriate when conventional indications are present (e.g., pulmonary embolism, proximal deep-vein thrombosis, atrial fibrillation, catheter-associated thrombosis). Tumor-directed therapy remains the primary determinant of outcomes. Prospective studies are needed to define optimal management strategies. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/view/CRD420251111117 , identifier CRD420251111117.

Purpose: Apolipoprotein B (apoB), a direct measure of atherogenic lipoprotein particles, is recommended by clinical guidelines for cardiovascular risk assessment, particularly when low-density lipoprotein cholesterol (LDL-C) underestimates risk. Despite these endorsements, apoB testing remains significantly underutilized in clinical practice. This study evaluated the knowledge and practices of physicians and pharmacists in Saudi Arabia regarding apoB testing and its role in lipid management and cardiovascular risk stratification. Methods: Cross-sectional survey-based study conducted with physicians and pharmacists across healthcare institutions using a validated questionnaire. Results: A total of 158 participants completed the questionnaire, including 80 physicians (50.6%) and 78 pharmacists (49.4%). The overall mean knowledge score was 4.70 ± 3.13 (out of a maximum score of 10). Participants specializing in family medicine, cardiology, and ambulatory care had the highest mean knowledge scores among specialties. Physicians demonstrated a significantly higher knowledge score than pharmacists (6.00 ± 2.99 vs 3.36 ± 2.69; P < 0.001). While 69.6% recognized apoB as a direct measure of atherogenic lipoprotein particles, only 53.8% correctly identified it as the most reliable marker of residual atherosclerotic cardiovascular disease risk in patients with lipid profile discordance. A significantly higher proportion of participants with high knowledge reported measuring apoB levels or considering it whenever available in their practice than those with moderate and low levels of knowledge (88.2%, 53.1%, and 24.1%, respectively; P < 0.001). Conclusion: ApoB testing remains underutilized among physicians and pharmacists in Saudi Arabia despite guideline recommendations. Targeted educational initiatives and national-level strategies are needed to enhance awareness and integration of apoB testing in risk assessment practices.