Background: Chronic kidney disease (CKD) and its advanced stage, end-stage renal disease (ESRD), affect millions worldwide and are associated with a paradoxical hemostatic imbalance—marked by both increased thrombotic and bleeding risks—which complicates anticoagulant use and demands clearer, evidence-based clinical guidance. Design: This study is a critical review synthesizing the current literature on anticoagulant therapy in CKD and ESRD, with emphasis on altered pharmacokinetics, clinical complications, and therapeutic adjustments. Data Sources: PubMed, Scopus, and Google Scholar were searched for articles discussing anticoagulation in CKD/ESRD, focusing on pharmacokinetics, clinical outcomes, and dosing recommendations. Study Selection: Studies examining the safety, efficacy, and pharmacokinetics of anticoagulants—including heparin, low-molecular-weight heparin (LMWH), warfarin, and direct oral anticoagulants (DOACs)—in CKD and ESRD populations were included. Data Extraction and Synthesis: Key findings were summarized to highlight the dose modifications, therapeutic considerations, and clinical challenges in managing anticoagulation in CKD/patients with ESRD. Emphasis was placed on balancing thrombotic and bleeding risks and identifying gaps in existing guidelines. Results: Patients with CKD and ESRD exhibit a paradoxical hypercoagulable state marked by platelet dysfunction, altered coagulation factors, and vascular endothelial damage. This condition increases the risk of thrombotic events, such as deep vein thrombosis (DVT) and pulmonary embolism (PE), while simultaneously elevating bleeding risks. Hemodialysis and CKD-associated variables further complicate the management of coagulation. Among anticoagulants, unfractionated heparin (UFH) is preferred due to its short half-life and adjustability based on activated partial thromboplastin time (aPTT). Low-molecular-weight heparins (LMWHs) offer predictable pharmacokinetics but require dose adjustments in CKD stages 4 and 5 due to reduced clearance. Warfarin necessitates careful dosing based on the estimated glomerular filtration rate (eGFR) to maintain an international normalized ratio (INR) ≤ 4, minimizing bleeding risks. Direct oral anticoagulants (DOACs), particularly Apixaban, are recommended for patients with eGFR < 15 mL/min or those on dialysis, although data on other DOACs in CKD remain limited. The lack of comprehensive guidelines for anticoagulant use in CKD and ESRD highlights the need for individualized, patient-centered approaches that account for comorbidities, genetics, and clinical context. Conclusions: Managing anticoagulation in CKD/ESRD is challenging due to complex coagulation profiles and altered pharmacokinetics. Judicious dosing, close monitoring, and patient-centered care are critical. High-quality randomized controlled trials are needed to establish clear guidelines and optimize therapy for this vulnerable population.

Embolic stroke of undetermined source (ESUS) is a clinical event with an undelineated embolic etiology after the initial stroke workup. Once stroke specialists confirm ESUS, evaluation of rhythm disorders such as atrial fibrillation, specific cardiac pathologies (cardiomyopathy, left atrial cardiopathy, left-atrial septal pouch, aortic or mitral valve disease, cardiac neoplasm, right-to-left shunts, or device-related thrombus), and acquired hypercoagulable states, which may occasionally be related to malignancy, should be performed. While most ESUS patients require appropriate antiplatelet therapy, certain subsets may require oral anticoagulation. However, routine prescription of oral anticoagulants in the absence of documented atrial fibrillation, cancer-related thrombosis, or cardiac thrombosis is discouraged. Shared decision-making between the patient and the physician about additional diagnostic and therapeutic decisions is particularly encouraged in this condition, given the limited availability of high-quality clinical data and considerable uncertainty about the safety and efficacy of therapeutic options and clinical outcomes.

Background: Percutaneous left atrial appendage occlusion (LAAO) is an established nonpharmacologic strategy for stroke prevention in atrial fibrillation (AF). Its comparative effectiveness and safety relative to contemporary medical therapy, including direct oral anticoagulants (DOACs), remain uncertain following recent large randomized controlled trials (RCTs). Methods: We performed a systematic review and meta-analysis of RCTs comparing catheter-based LAAO with medical therapy in AF patients. PubMed, CENTRAL, and ScienceDirect were searched from inception through May 2026. Dichotomous outcomes were pooled as risk ratios (RRs) with 95% confidence intervals (CIs) using random-effects models. The primary outcome was the composite primary endpoint. Secondary outcomes included all-cause death, cardiovascular death, all stroke/TIA, ischemic stroke/TIA, systemic embolism, major bleeding, and nonprocedural major bleeding. Risk of bias was assessed using ROB 2. Results: Six RCTs were included, contributing 7073 participants (3729 LAAO; 3344 medical therapy). LAAO was not associated with significant differences in the composite endpoint (RR 1.02; 95% CI 0.85–1.23), all-cause death (RR 1.02; 95% CI 0.79–1.31), cardiovascular death (RR 0.93; 95% CI 0.67–1.29), all stroke/TIA (RR 1.06; 95% CI 0.81–1.38), ischemic stroke/TIA (RR 1.24; 95% CI 0.88–1.76), systemic embolism (RR 0.76; 95% CI 0.12–4.77), or total major bleeding (RR 0.93; 95% CI 0.77–1.13). LAAO significantly reduced nonprocedural bleeding (RR 0.54; 95% CI 0.46–0.63; p < 0.0001; I² = 0.0%). Heterogeneity was low to moderate across outcomes. Conclusions: No significant differences were observed between LAAO and medical therapy for the composite endpoint, mortality, or thromboembolic outcomes; however, confidence intervals for ischemic stroke/TIA and systemic embolism remained wide and cannot exclude a clinically meaningful excess of thromboembolic events after LAAO. LAAO was associated with a substantial and consistent reduction in nonprocedural bleeding. These findings suggest LAAO may be considered an individualized alternative to oral anticoagulation for selected patients with high bleeding risk or anticoagulation intolerance, weighing upfront procedural risk against this bleeding benefit, while uncertainty for rare thromboembolic outcomes remains to be resolved.