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Objective: Hemodialysis catheter-related right atrial thrombus (CRAT) is a rare and fatal complication related with catheter. Treatment recommendations are controversial. We reported our institution's recent three cases in managing CRAT and review and analyze the reported cases of CRAT in hemodialysis patients., Methods: A systematic search of the PubMed, Embase and Web of Science databases was conducted to identify the therapy and outcome data in hemodialysis CRAT patients., Results: From 1975 to November 2023, a total of previous 144 cases which reported in the literatures and three new cases in our institution of CRAT in hemodialysis were included and analyzed. Overall mortality was 18.1% (26/144). Most of cases can be detected by echocardiography. Thirty-three patients had no treatment, except for catheter removal, replacement or antibiotics, but eleven of them have died. Thrombolytic therapy was adopted in 14 cases but only nine cases was successful, the remaining cases need to further therapy. Eventually, 71 cases have been treated by anticoagulation and 34 cases received thrombectomy., Conclusions: We recommend that the replacement of the catheter and anticoagulation combined with thrombolysis is a preferred therapy. Thrombectomy should be considered when other methods fail or new complication happened. Thrombolysis alone has a low success rate but may be useful in combination with anticoagulant therapy., Competing Interests: Declarations Ethics approval and consent to participate The case was approved by the Human Ethics Committee of the First Affiliated Hospital of Chongqing Medical University (Number:2023 − 315). Consent for publication The patient provided written informed consent. Clinical trial number Not applicable. Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

Background: In symptomatic high-risk patients with severe mitral valve regurgitation (MR), who are not eligible for surgery, Transcatheter edge-to-edge repair (TEER) or transcatheter mitral valve replacement (TMVR) may be an option, especially when surgical mitral valve repair by annuloplasty has been performed earlier. After TMVR, the appropriate anticoagulation regimen is still matter of debate., Case Presentation: We here report on a 78-year-old frail lady with heart failure and atrial fibrillation who underwent surgical reconstruction of the mitral valve nine years ago. Due to high surgical risk and after heart team discussion, TMVR using a transcatheter aortic valve prosthesis (valve-in-ring concept) was performed successfully via the transapical access route. Several months later, an excellent result could be confirmed. Since surgical excision of the left atrial appendage was carried out during first surgery, oral anticoagulation was withdrawn. Two months later, the patient presented with a massive LA thrombus mass and severe stenosis of the mitral valve prosthesis requiring re-do surgery., Conclusions: Management of anticoagulation in patients with atrial fibrillation and successfully performed LAA excision is still a matter of debate, in particular after transcatheter heart valve implantation in mitral position. TMVR devices may be very thrombogenic. Thus, caution should be used whenever discontinuing oral anticoagulation in these patients. Despite the lack of evidence, withdrawal of anticoagulation should be avoided here, especially in the absence of bleeding complications. Left atrial appendage closure or excision should not influence this decision., Competing Interests: Declarations Ethics approval and consent to participate Not applicable. Consent for publication Written informed consent was given by the patient. Competing interests The authors declare no competing interests. Clinical trial number Not applicable., (© 2024. The Author(s).)

Introduction: Vitamin-K antagonists (VKA) are considered the first-line anticoagulants for thrombotic antiphospholipid syndrome (TAPS), particularly with triple positivity or arterial events. However, thrombotic recurrence remains high despite anticoagulation and other clinical issues may arise. Long-term parenteral anticoagulants may therefore be considered, however little is known about the viability of fondaparinux in this setting., Materials and Methods: We describe the efficacy and safety of long-term fondaparinux for TAPS (>3-months duration) treated at a single centre in the UK. Clinical features and the outcomes of recurrence and bleeding were reviewed using electronic patient records., Results: 46 patients were identified with history of either venous or arterial TAPS and a total 175 patient-years using fondaparinux (median duration 2.7 years/patient (IQR 1.4-4.8)). 43 (93%) had VKA as first-line anticoagulation with a median duration of 6.5 years (IQR 4.0 - 9.8). All patients received fondaparinux as second-to fourth-line anticoagulation.Thrombosis recurrence occurred in 1 (1%) patient (0.6 events/100-patient years). Major, clinically relevant non-major (CRNM) or minor bleeding occurred in 2 (7%), 5 (10.9%) and 8 (17.4%) patients respectively. Major/CRNM bleeding rates were 1.1 and 2.9 events/100-patient-years. Age >65years was associated with bleeding ( p = .047) and concurrent antiplatelets were associated with major/CRNM bleeding ( p = .011). Logistic regression showed increasing age was associated with bleeding (OR = 1.097, p = .009)., Conclusions: We suggest that fondaparinux may be used for TAPS when VKA is not appropriate. Thrombotic recurrence was infrequent, and the number of major bleeding events appeared comparable to conventional therapies., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: This study aims to evaluate the safety and efficacy of a short-term, low dose, weight-based subcutaneous enoxaparin protocol (SEP) in maintaining the patency of arteriovenous (AV) access with recurrent thrombosis., Methods: Prospective follow-up of 25 patients who presented to a tertiary institution with recurrent AV access thrombosis and treated with anticoagulation according to SEP following successful thrombectomy. Patency and safety outcomes of SEP were studied., Results: The participants were 66.4 ± 10.2 years old and predominantly male (60%) and of Chinese ethnicity (72%). The AV accesses had a median age of 1.4 (0.6, 5.6) years with 60% being non-autogenous arteriovenous access while 40% were autogenous arteriovenous access. Thrombolytic agents (urokinase (72%) or alteplase (28%)) were used in all procedures while adjunct thrombectomy device was used in only four procedures. The mean dose of enoxaparin was 36.0 ± 8.2 mg or 0.64 ± 0.1 mg/kg/day for a mean duration 30.0 days (Interquartile range: 27.5, 31.0). One patient developed minor bleeding episode. Kaplan-Meier analysis demonstrated that the mean thrombosis-free survival pre- versus post-SEP adoption was 27.3 (95% CI 17.9-36.7) versus 183.5 (95% CI 100.1-266.9) days ( p  < 0.001). After adjusting for the type of thrombolytic agent, use of adjunct thrombectomy device, cutting balloon, drug-coated balloon, and stent graft, SEP remained a significant factor associated with longer thrombosis-free patency (HR 0.166: 95% CI 0.070-0.392, p  < 0.001)., Discussion: SEP appears to be a feasible and safe thromboprophylaxis method to improve thrombosis-free patency for AV access with recurrent thrombosis., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

BACKGROUND Incidental findings of renal infarct secondary to thrombosis in acutely ill patients present a unique challenge in diagnosis. We present a case of idiopathic renal infarct to highlight its workup and management and encourage further investigation of renal infarctions. CASE REPORT A 68-year-old woman with a past medical history of diet-controlled diabetes, hypertension, and hyperlipidemia presented to the Emergency Department (ED) for abdominal pain. She was found to be in diabetic ketoacidosis with pyelonephritis, so she was admitted to the Intensive Care Unit (ICU) for insulin and dextrose drip. Due to her abdominal pain, she underwent computed tomography (CT) of her abdomen and pelvis with contrast. This revealed multifocal infarcts of her right kidney with noncalcified thrombus at the proximal right renal artery. Subsequent CT angiography confirmed a right renal artery thrombus. She was started on subcutaneous enoxaparin and downgraded to basic level of care. Her history was negative for prior thrombosis, hypercoagulable state, and abdominal trauma. Echocardiogram and limited hypercoagulable workup were largely unremarkable. A multidisciplinary team evaluated the patient and recommended no surgical intervention. Following downgrade from the ICU, the patient was transitioned from enoxaparin to apixaban. She was discharged with plans for anticoagulation for 6 months, aspirin daily, and repeat CT angiogram abdomen/pelvis in 1 month. CONCLUSIONS This case illustrates the difficulties in elucidating the cause of incidental renal thrombosis in an acutely ill patient. Diagnostic workup is limited in the inpatient setting, but therapeutic anticoagulation remains the standard of treatment regardless of etiology.

Cancer-associated thrombosis (CAT) remains a challenging aspect of managing patients with cancer. This review discusses evidence regarding anticoagulants in the treatment of CAT, with particular emphasis on direct oral anticoagulants (DOAC). Apixaban, rivaroxaban and edoxaban have proven attractive alternatives to low-molecular weight heparins, and interactions with medical cancer treatment does not pose a major challenge. The majority of guidelines have endorsed the use of DOAC, and we highlight points to consider when choosing the optimal anticoagulant for the individual patient., (Published under Open Access CC-BY-NC-BD 4.0. https://creativecommons.org/licenses/by-nc-nd/4.0/.)

Background: Patients with mechanical prosthetic heart valves must be treated with vitamin K antagonists (VKA) due to an increased risk of valve thrombosis and systemic embolism., Objectives: To assess the effects of the COVID-19 pandemic on VKA treatment control in patients with mechanical prosthetic heart valves., Methods: We conducted a retrospective nationwide cohort study using the Clalit Health Services database. The cohort included patients who underwent either aortic or mitral valve replacement using a prosthetic mechanical valve. The primary outcomes included the overall time in therapeutic range (TTR) and the percent of patients with a TTR < 50% during the first year of the COVID-19 pandemic compared to preceding year., Results: The cohort included 2381 patients. The percentage of patients who had at least two international normalized ratio (INR) tests during the first year of the COVID-19 pandemic was significantly lower compared to the year preceding the pandemic (81% and 87%, respectively, P < 0.001). In both years, the percentage of patients without any documented INR test was high (31.5% in the first COVID-19 pandemic year and 28.9% in the preceding year, P < 0.001). TTR was significantly lower during the 1st year of the COVID-19 pandemic compared to the preceding year (68.1% ± 26 and 69.4% ± 24, P = 0.03). A TTR > 50% was demonstrated in 78% and 81% during the pandemic and the preceding year, P = 0.009., Conclusions: We noted overall poor VKA control in patients with mechanical heart valves. During the COVID-19 pandemic, VKA control became even worse as reflected by significantly lower TTR and INR tests rates.

Background: Congenital portosystemic shunts (CPSS) are rare congenital abnormalities causing abnormal blood flow between the portal vein and systemic circulation. This study reports on the peri-operative anticoagulation management of CPSS patients post closure, focusing on the incidence of thrombotic and bleeding complications., Methods: This is a single-center retrospective analysis of CPSS patients who underwent surgery or endovascular intervention between 2005 and 2021. The protocol included unfractionated heparin (UFH) during and immediately after surgery, followed by either warfarin or low molecular weight heparin (LMWH) postoperatively. Outcomes assessed included postoperative thrombotic and bleeding complications., Results: A total of 44 patients were included. Postoperatively, 89% received treatment-dose UFH, transitioning to warfarin or LMWH at discharge. Thrombotic complications occurred in 16% of patients, predominantly in the superior mesenteric vein. Surgical interventions and continuous infusion of tissue plasminogen activator (tPA) were used for clot resolution. Bleeding complications were observed in 64% of patients, primarily managed with transfusions and temporary UFH interruption. No deaths related to thrombotic, or bleeding events were reported., Conclusions: Our findings underscore the delicate balance required in anticoagulation management for CPSS patients, revealing an occurrence of both thrombotic and bleeding complications postoperatively., Levels of Evidence: Level II, retrospective study., Competing Interests: Conflicts of interest None of the authors have financial disclosures related to the submitted work., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Purpose of Review: Although lung transplantation stands as the gold standard curative therapy option for end-stage lung disease, the scarcity of available organs poses a significant challenge in meeting the escalating demand. This review provides an overview of recent advancements in ambulatory respiratory assist systems, selective anticoagulation therapies that target the intrinsic pathway, and innovative surface coatings to enable permanent respiratory support as a viable alternative to lung transplantation., Recent Findings: Several emerging ambulatory respiratory assist systems have shown promise in both preclinical and clinical trials. These systems aim to create more biocompatible, compact, and portable forms of extracorporeal membrane oxygenation that can provide long-term respiratory support. Additionally, innovative selective anticoagulation strategies, currently in various stages of preclinical or clinical development, present a promising alternative to currently utilized nonselective anticoagulants. Moreover, novel surface coatings hold the potential to locally prevent artificial surface-induced thrombosis and minimize bleeding risks., Summary: This review of recent advancements toward permanent respiratory support summarizes the development of ambulatory respiratory assist systems, selective anticoagulation therapies, and novel surface coatings. The integration of these evolving device technologies with targeted anticoagulation strategies may allow a safe and effective mode of permanent respiratory support for patients with chronic lung disease., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Patients with thrombotic antiphospholipid syndrome (APS) are at high risk for recurrent thrombosis, and indefinite anticoagulation is recommended. Patients with APS merit indefinite anticoagulation, and vitamin K antagonists (VKAs) have historically been the standard treatment. Direct oral anticoagulants (DOACs) present an appealing alternative to VKAs. Due to their pharmacokinetic and pharmacodynamic characteristics, DOACs offer advantages over VKAs, namely the lack of need for laboratory monitoring, the usage of a fixed dosage, and the absence of significant interaction with dietary components and drugs. The efficacy and safety of DOACs in patients with APS have been studied in four phase II/III clinical trials (three with rivaroxaban and one with apixaban). These studies showed DOACs' inferiority compared to VKAs in preventing recurrent thrombosis. Recurrence was significantly greater in patients with arterial thrombotic events and a triple positivity for antiphospholipid antibodies. No differences were observed in the incidence of venous thromboembolism between both groups. Major bleeding was similar in patients treated with DOACs or VKAs. Several observational studies have reported similar results. This review aims to analyse the existing evidence on the efficacy and safety of DOACs for secondary prevention in patients with APS.

Concomitant direct oral anticoagulants (DOACs) and tyrosine kinase inhibitor targeting vascular endothelial growth factor receptor (anti-VEGF TKI) have been associated with a higher risk of bleeding. Nevertheless, concomitant administration seems frequent in clinical practice in patients with cancer-associated thrombosis and appears to be safe according to the retrospective study by Boileve A. et al. But the risk of an additional pharmacokinetic interaction between anti-VEGF TKI and DOACs must be considered, in case of P-glycoprotein (P-gp) inhibition by the TKI. We describe a case report with a major bleeding event in a renal metastatic cancer patient treated with cabozantinib and rivaroxaban. This case highlights the difficult therapeutic decision in a complex patient with cancer-associated thrombosis, who refused the anticoagulant subcutaneous route. Accumulation of bleeding risk factors (genito-urinary tumor localization) was additive to several pharmacodynamic interactions (acetylsalicylic acid, venlafaxine) and a potential pharmacokinetic interaction between cabozantinib and rivaroxaban. Indeed, cabozantinib-related P-glycoprotein inhibition could have led to a supratherapeutic level of rivaroxaban, contributing partly to the bleeding event. Before combining an anti-VEGF TKI and DOACs, a multidisciplinary pretherapeutic assessment seems crucial to evaluate the patient's bleeding risk factors, pharmacodynamic interactions, and the risk of pharmacokinetic interactions mediated by P-gp., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Introduction and Objective: Mitral stenosis (MS) is one of the most frequently observed valvular heart lesions in developing countries and is due to different etiologies. The effects of anticoagulation in different types of left atrial appendage (LAA) are unknown. The current study aimed to determine the resolution of LAA thrombus on transesophageal echocardiography (TEE) after three months of optimal anticoagulation in patients with different types of LAA at baseline cardiac computed tomography of patients with severe MS., Methods: This prospective cohort study observed the frequency of LAA thrombus resolution after three months of anticoagulation therapy in patients with severe MS. The response rate in different morphologies of LAA and locations was also assessed. Thrombus resolution after three months of warfarin therapy was assessed on repeat TEE., Results: A total of 88 patients were included, mean age 37.95±11.87 years. Repeat TEE showed thrombus resolution in only 27.3% of patients. The rate of thrombus resolution was 8/12 (66.7%), 4/28 (14.3%), 8/36 (22.2%), and 4/12 (33.3%) for patients with cactus, cauliflower, chicken wing, and windsock LAA type, respectively. The resolution rate was 0/12 (0%), 4/44 (9.1%), and 20/32 (62.5%) for patients with thrombus in the base, body, and tip of the LAA, respectively., Conclusion: The cactus type of LAA morphology and thrombus at the LAA tip responded well to three months of anticoagulation, however, patients with thrombus in the LAA base and body and cauliflower and chicken wing morphology were non-responders and could benefit from early referral for surgical management., (Copyright © 2024 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.)

A systemic inflammatory response occurs during SARS-CoV2 infection and is associated with hypercoagulability and thrombotic events. From March 2020 in our hospital different dosages of low-molecular weight heparin (LMWH) were introduced according to the level of patient care intensity. Because bleeding episodes occurred in hospitalized COVID-19 patients on heparin, the dosage of LMWH at the end of first wave was tailored on the severity of COVID-19. The aim of this study is to describe bleeding and thrombotic events in patients hospitalized with SARS-CoV2 infection on LMWH therapy in the two waves of COVID-19 and analyze the factors associated with these events. Among 1143 patients enrolled in the COVID-19 Network registry, 912 were included in the analysis, 537 of them admitted during the first wave and 375 during the second. Bleeding events were 30 (3.3%): 22 (2.4%) major and 8 (0.9%) non-major. Arterial and venous thrombotic events were 6 (0.7%) and 24 (2.6%). The incidence of venous thrombotic events was higher in the first than in the second wave (0.29% [95% CI 0.20-0.45] events/day vs. 0.05% [95% CI 0.02-0.16]), with a 71% risk reduction (95% CI 22%-94%). The incidence of bleeding was 0.33% (95% CI 0.22-0.50) vs 0.14% events/day (95% CI 0.07-0.28), with no statistical between-wave difference (HR 0.41 95% CI 0.16-1.08). After adjusting for the competing risks of death and comorbidities, patients in the second wave had lower odds to have thrombotic events than in the first wave (0.24 HR [95% C.I. 0.07-0.89]). In this retrospective study on COVID-19 we found a low rate of hemorrhagic and thrombotic events, that may be explained by the absence in the case material of patients admitted to intensive care unit., (© 2024. The Author(s), under exclusive licence to Società Italiana di Medicina Interna (SIMI).)

Objective: The aim of this prospective study was to (1) objectively quantify the impact of sex on platelet function in patients with peripheral artery disease (PAD) taking antiplatelet and anticoagulant medications and (2) to develop and test a personalized, iterative algorithm that personalizes thromboprophylaxis that incorporates platelet function testing., Background: Women with PAD have worse outcomes as compared with their male counterparts despite having lower risk factors. This health disparity may be mitigated by personalizing thromboprophylaxis regimens., Methods: Patients undergoing revascularization were enrolled. Serial thromboelastography (TEG) and TEG with platelet mapping (TEG-PM) were performed up to 6 months postoperatively to determine objective coagulation profiles. In a subset of patients, the Antiplatelet Coagulation Exactness (ACE) algorithm was implemented, where patients were iteratively evaluated with TEG and given antiplatelet medications to maintain platelet inhibition at >29%. Statistical analysis was performed using unpaired t test, analysis of variance, and Fisher exact test., Results: One hundred eighty-one patients met the study criteria. Fifty-eight (32%) patients were females and 123 (68%) were males. In the Aspirin cohort, females showed significantly greater clot strength as maximum amplitude - arachidonic acid (MA AA ) and significantly lower platelet inhibition than males: (37.26 vs 32.38, P <0.01) and (52.95% vs 61.65%, P <0.05), respectively. In the Clopidogrel cohort, females showed higher Maximum Amplitude - Adenosine Diphosphate (MA ADP ) (42.58 vs 40.35, P = not significant [NS]) compared with males. Females on dual antiplatelet therapy had higher MA ADP (39.74 vs 35.07, P =NS) and lower platelet inhibition (45.25% vs 54.99%, P= NS) than males. The incidence of thrombosis of the revascularized segment, defined as thrombotic event, was objectively identified on an arterial duplex. Women showed significantly higher thrombotic events than men (22.95% vs 10.57%, P< 0.05) on the same medication. In our pilot study, implementation of the ACE algorithm led to a significant decrease in the thrombosis rate (3%), including nonthrombotic events for females, versus the historic thrombotic rate (22%) from our institution., Conclusions: Women with PAD exhibited higher platelet reactivity, clot strength, and reduced platelet inhibition in response to antiplatelet therapy. The use of the ACE algorithm to tailor antiplatelet medication in patients with PAD post-revascularization, resulted in a significant decrease in thrombotic event rates. This may serve as an opportune way to mitigate outcome sex-specific disparities caused by inadequate thromboprophylaxis in women., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: American Association for Thoracic Surgery and The International Society for Heart and Lung Transplantation (AATS/ISHLT) guidelines recommend warfarin in patients with continuous-flow left ventricular assist devices (LVADs) to reduce the risk of device thrombosis and systemic embolization. Left ventricular assist device patients often undergo elective and emergent procedures that require interrupted anticoagulation. Data and experience vary on the optimal strategy to rapidly reverse warfarin in LVAD patients when an emergent procedure is planned., Objective: The purpose of this study was to describe the use of 4-factor prothrombin complex concentrate (PCC4) for warfarin reversal in patients with LVADs undergoing elective and emergent procedures., Methods: This retrospective, single-center, cohort review describes the use of PCC4 in patients with LVADs who require warfarin reversal for elective or emergent procedures. The primary outcome was a composite incidence of pump thrombosis, venous thromboembolism, and ischemic stroke within 30 days of PCC4 administration., Results: In total, 14 patients received 17 administrations of PCC4. One patient received 3 administrations, and 1 other patient received 2 administrations during separate encounters. The median dose was 500 units or 6.6 units/kg (range = 4.2-14.1 units/kg). Of the PCC4 administrations, 82% (14/17) were for low bleed risk procedures and 76% (13/17) were for elective procedures. There were no cases of pump thrombosis, venous thromboembolism, or stroke within 30 days of the procedure., Conclusions and Relevance: Low-dose PCC4 appears to be a safe and effective temporary reversal strategy for patients with LVADs undergoing low-bleed risk elective procedures., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Aims: Ischemic strokes in patients on oral anticoagulant therapy (OAT) despite optimal adherence pose a therapeutic challenge. We assessed the utility of transesophageal echocardiography (TEE) in identifying potential competing cardiac causes for stroke that occurred despite adequate OAT., Methods: This retrospective observational study included patients admitted for acute ischemic stroke between January 2022 and June 2023 who were on OAT for an established long-term indication. Transthoracic and transesophageal echocardiography, along with assessment of OAT adherence, were conducted. Demographic data, OAT details, and stroke characteristics were analysed to determine the influence of TEE findings on therapeutic decisions., Results: We included 26 patients. TEE identified potential cardiac competing stroke mechanisms in 88% of cases, with valvular thrombi and left atrial or appendage thrombus being predominant. Infective endocarditis, often asymptomatic, was unexpectedly prevalent. TEE significantly influenced therapeutic decisions, especially in cases where transthoracic echocardiography was inconclusive., Conclusions: TEE may be crucial for unravelling the mechanisms of ischemic stroke in patients on adequate OAT, guiding precise therapeutic strategies and potentially reducing the risk of recurrent embolic events. Our findings underscore the limitations of standard echocardiography in detecting cardiac embolic sources and emphasize the importance of tailored decision-making in secondary stroke prevention., (Copyright © 2024 Italian Federation of Cardiology - I.F.C. All rights reserved.)

Objective: Extracorporeal membrane oxygenation (ECMO) requires systemic anticoagulation to reduce the risk of thromboembolic events. Despite its historic role, activated clotting time (ACT) remains a widely used heparin monitoring method. Systematic evidence on the association of ACT-guided monitoring with hemorrhagic or thromboembolic complications does not exist., Design: Systematic literature review and meta-analysis (Scopus and PubMed, July 2023)., Setting: All cohort studies., Participants: Patients receiving ECMO support., Intervention: Anticoagulation monitoring with ACT., Measurements and Main Results: We identified 3,177 publications, with 8 studies reporting the average ACT values for patients with and without bleeding. Meta-analysis revealed no significant difference in the compared groups (SMD = 0.69; 95% CI -0.05 to 1.43, p = 0.069; I 2  = 87.4%). Three studies (n = 117 patients) reported on the average ACT values for patients with thrombosis, without significant differences in ACT between patients with and without thrombosis (SMD = 0.47; 95% CI -0.50 to 1.44, p = 0.342; I 2  = 81.1%)., Conclusions: Even though ACT is a widely used heparin monitoring tool, the evidence on its association with hemorrhagic or thromboembolic events is still controversial and limited. Further studies are essential to elucidate the role of ACT in anticoagulation monitoring during ECMO support., Competing Interests: Declaration of competing interest All authors have no conflicts of interest., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Left ventricular (LV) thrombus formation remains a post-acute myocardial infarction (AMI) complication even in the modern era of early reperfusion. The optimal anticoagulation regimen in this clinical scenario is poorly defined. The present meta-analysis sought to investigate the efficacy and safety profile of direct oral anticoagulants (DOACs) compared with vitamin K antagonists (VKAs) for the management of LV thrombus after AMI. A systematic literature review was conducted in electronic databases to identify studies reporting efficacy and safety outcome data regarding the use of DOACs versus VKAs for patients with LV thrombus after AMI. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated, and random-effects meta-analyses were conducted to synthesize pooled ORs. Eight studies comprising a total of 605 patients were included. DOACs were associated with an almost twofold higher likelihood of thrombus resolution compared with VKAs (pooled OR 1.95 [1.25 to 3.04], p = 0.003, I 2 = 0%), and decreased the risk of systemic embolism by 70% (pooled OR 0.30 [0.12 to 0.75]; p = 0.01, I 2 = 0%). The use of DOACs was associated with a 54% lower risk of bleeding compared with VKAs (pooled OR 0.46 [0.26 to 0.84], p = 0.01, I 2 = 0%). Overall, patients receiving DOACs had a 63% lower risk of reaching the composite outcome of safety and efficacy compared with patients using VKAs (pooled OR 0.37 [0.23 to 0.60], p <0.0001, I 2 = 0%). In conclusion, DOACs appear to have a more favorable efficacy and safety profile compared with VKAs for the management of LV thrombus related to AMI., Competing Interests: Declaration of competing interest The authors have no competing interests to declare., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Aims: The optimal antithrombotic therapy to balance the risk of thrombosis and bleeding in patients who undergo transcatheter aortic valve implantation (TAVI) is unknown. This systematic review/network meta-analysis of randomized controlled trials (RCTs) aimed to evaluate the efficacy and safety of different oral anticoagulant (OAC) and antiplatelet regimens in patients post-TAVI., Methods and Results: MEDLINE, Embase, CENTRAL, and ClinicalTrials.gov were searched from inception to April 2023. Co-primary outcomes were all-cause death and major bleeding. We conducted Bayesian network meta-analyses to compare all interventions simultaneously. For each outcome, we generated odds ratios (ORs) with 95% credible intervals using a random-effects model with informative priors, and ranked interventions based on mean surface under the cumulative ranking curve. We included 11 RCTs (n = 6415), including 1 unpublished RCT. Three trials enrolled patients with an indication for an OAC. Overall risk of bias was low or with some concerns. Median age was 81 years. Median follow-up was 6 months. The combination of OAC plus single antiplatelet therapy (SAPT) increased the risk of all-cause death compared with dual antiplatelet therapy (DAPT) (OR 1.78, 95% credible interval 1.15-2.77). No other comparisons for all-cause death were significantly different. For major bleeding, SAPT reduced the risk compared with DAPT, direct-acting OAC, and OAC + SAPT (OR 0.20-0.40), and DAPT reduced the risk compared with OAC + SAPT. SAPT and DAPT ranked best for all-cause death, while SAPT ranked best for major bleeding., Conclusion: In post-TAVI patients, SAPT may provide the optimal balance of reducing thrombotic events while minimizing the risk of bleeding., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Atrial fibrillation (AF) is the most frequently encountered arrhythmia in the clinical practice and is associated with stroke. In clinical practice, CHAD2DS2-VASc score is used as a tool to decide whether anticoagulation is needed. In those patients with high bleeding risk or falls, surgical ligation of the left atrial appendage (LAA) or percutaneous closure devices are strategies used to mitigate these challenges. However, there is no guideline advising on what patient's specific factors should be considered in determining initiation or continuation of anticoagulation post LAA ligation. Herein, we report the case of a patient with surgical ligation who developed large atrial thrombus requiring emergent median sternotomy., (Copyright© South Dakota State Medical Association.)

Background: Clot-in-transit is associated with high mortality, but optimal management strategies remain uncertain. The aim of this study was to compare the outcomes of different treatment strategies in patients with clot-in-transit., Methods: This is a retrospective study of patients with documented clot-in-transit in the right heart on echocardiography across 2 institutions between January 2020 and October 2023. The primary outcome was a composite of in-hospital mortality, resuscitated cardiac arrest, or hemodynamic decompensation., Results: Among 35 patients included in the study, 10 patients (28.6%) received anticoagulation alone and 2 patients (5.7%) received systemic thrombolysis, while 23 patients (65.7%) underwent catheter-based therapy (CBT; 22 mechanical thrombectomy and 1 catheter-directed thrombolysis). Over a median follow-up of 30 days, 9 patients (25.7%) experienced the primary composite outcome. Compared with anticoagulation alone, patients who received CBT or systemic thrombolysis had significantly lower rates of the primary composite outcome (12% versus 60%; log-rank P <0.001; hazard ratio, 0.13 [95% CI, 0.03-0.54]; P =0.005) including a lower rate of death (8% versus 50%; hazard ratio, 0.10 [95% CI, 0.02-0.55]; P =0.008), resuscitated cardiac arrest (4% versus 30%; hazard ratio, 0.12 [95% CI, 0.01-1.15]; P =0.067), or hemodynamic deterioration (4% versus 30%; hazard ratio, 0.12 [95% CI, 0.01-1.15]; P =0.067)., Conclusions: In this study of CBT in patients with clot-in-transit, CBT or systemic thrombolysis was associated with a significantly lower rate of adverse clinical outcomes, including a lower rate of death compared with anticoagulation alone driven by the CBT group. CBT has the potential to improve outcomes. Further large-scale studies are needed to test these associations., Competing Interests: Dr Bangalore is on the Advisory Board of Abbott Vascular, Boston Scientific, Biotronik, Amgen, Pfizer, Merck, Reata, Inari, and Truvic. The other authors report no conflicts.

Background: Left atrial thrombus (LAT) formation is associated with thromboembolic events., Objective: To investigate the incidence and associated factors of LAT in patients with atrial fibrillation (AF) who had been receiving anticoagulation therapy for more than 4 weeks, and to develop a prediction model using clinical and echocardiographic features., Methods: Medical records of 1,122 patients with AF (mean age, 59.4 ± 11.0 years, 58.3% male) who were on anticoagulation more than 4 weeks and underwent transesophageal echocardiography (TEE) were evaluated. The main outcome was the presence of LAT on TEE., Results: Warfarin and non-vitamin K oral anticoagulants were used in 74.4% and 25.6% of the patients at the time of examination, respectively. LAT was present in 60 patients (5.3%). Presence of LAT on TEE was associated with age ≥ 75 years (odds ratio [OR] 2.13 [95% confidence interval, 0.94-4.58]), persistent/permanent AF (OR 2.61 [1.42-4.93]), CHA 2 DS 2 -VASc score ≥ 3 points (OR 1.91 [1.05-3.48]), left ventricular ejection fraction < 40% (OR 2.35 [1.07-4.81]), and severe left atrial enlargement (OR 3.52 [1.89-6.79]). The presence of moderate-to-severe mitral regurgitation was associated with a lower risk of LAT (OR 0.13 [0.04-0.34]). A scoring system composed of the aforementioned predictors showed excellent discrimination performance (area under the curve 0.791 [95% CI, 0.727-0.854])., Conclusions: LAT was present in a considerable number of patients who were already receiving anticoagulation therapy. A prediction model that combines clinical and echocardiographic predictors could be useful in distinguishing patients who require imaging evaluations before left atrial intervention., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)

Thrombotic manifestations, mainly venous thromboembolism (VTE) and stroke, are the most common and potentially life-threatening presentations of antiphospholipid syndrome (APS). The management of APS requires the assessment of the antiphospholipid antibodies (aPL) profile, of concurrent systemic lupus erythematosus or other systemic autoimmune diseases and the presence of risk factors for cardiovascular disease and bleeding. Anticoagulation with vitamin K antagonists (VKA) remains the cornerstone of therapy for thrombotic APS. As platelets play a central role in APS, low-dose aspirin is the first option for primary thromboprophylaxis in asymptomatic aPL carriers, and also plays a role as combination therapy with VKAs in arterial thrombosis. Treatment with direct oral anticoagulants (DOACs) could be considered in certain low-risk situations, although they are not recommended in patients with arterial thrombosis or triple positive aPL. Adjuvant therapies such as hydroxychloroquine and statins may be useful in complex settings such as thrombotic recurrences or high risk of bleeding. In this article, we review the evidence and the recommendations of the guidelines for the treatment of APS, and provide a critical and practical approach of its management from our clinical perspective., (Copyright © 2024 Elsevier España, S.L.U. All rights reserved.)

All foreign bodies inserted in the circulatory system are thrombogenic and require temporary or lifelong antithrombotic therapies to prevent thrombosis. The adequate level of anticoagulation during the first few months determines the long-term durability, particularly for mechanical prostheses, and also for biological valves. Suboptimal anticoagulation is the most frequent source of mechanical valve thrombosis (MVT). The patient's clinical presentation decides how mechanical prosthetic valve obstruction is managed. If the mechanical valve thrombosis is obstructive and the patient is in a critical condition with hemodynamic instability, an immediate surgical intervention should be performed. The thrombolytic treatment is an option for left mechanical valve thrombosis in patients who have high surgical risk and no contraindications and also for right heart valve thrombosis. In non-obstructive thrombosis on the mechanical valve, patients can be asymptomatic, requiring optimization of the anticoagulant treatment. Both obstructive and non-obstructive thrombus formed on the mechanical prosthesis can result in embolic events. If the thrombus persists following anticoagulant treatment, the recommended options include thrombolytic treatment or redo surgery. Pannus can also cause obstruction of the prosthesis for which surgical treatment is the only option. While these clinical scenarios may initially appear to have straightforward solutions in terms of surgery, thrombolysis, or effective anticoagulation, real-world clinical experience often proves more complex. For instance, a patient with some usual comorbidities and non-obstructive mechanical valve thrombosis, experiencing symptoms solely by repeated systemic embolizations, might undergo all three therapeutic options due to the unpredictable nature of MVT. Therefore, treatment indications can intersect both on the time axis and depending on the patient's clinical status and the expertise of the center where he is hospitalized. Moreover, the European and American guidelines show subtle but important differences. The aim of this review was to compare these differences, comment on recent studies and evidence gaps, propose a more pragmatic algorithm combining all current recommendations, and highlight important research directions for this disease that has dominated the cardiovascular landscape for more than five decades, but for which there have been no significant recent changes in management., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Objective: The initiation of extracorporeal membrane oxygenation (ECMO) triggers complex coagulation processes necessitating systemic anticoagulation. Therefore, anticoagulation monitoring is crucial to avoid adverse events such as thrombosis and hemorrhage. The main aim of this work was to analyze the association between anti-Xa levels and thrombosis occurrence during ECMO support., Design: Systematic literature review and meta-analysis (Scopus and PubMed, up to July 29, 2023)., Setting: All retrospective and prospective studies., Participants: Patients receiving ECMO support., Intervention: Anticoagulation monitoring during ECMO support., Measurements and Main Results: A total of 16 articles with 1,968 patients were included in the review and 7 studies in the meta-analysis (n = 374). Patients with thrombosis had significantly lower mean anti-Xa values (standardized mean difference -0.36, 95% confidence interval [CI] -0.62 to -0.11, p < 0.01). Furthermore, a positive correlation was observed between unfractionated heparin infusion and anti-Xa levels (pooled estimate of correlation coefficients 0.31, 95% CI 0.19 to 0.43, p < 0.001). The most common adverse events were major bleeding (42%) and any kind of hemorrhage (36%), followed by thromboembolic events (30%) and circuit or oxygenator membrane thrombosis (19%). More than half of the patients did not survive to discharge (52%)., Conclusions: This work revealed significantly lower levels of anti-Xa in patients experiencing thromboembolic events and a positive correlation between anti-Xa and unfractionated heparin infusion. Considering the contemplative limitations of conventional monitoring tools, further research on the role of anti-Xa is warranted. New trials should be encouraged to confirm these findings and determine the most suitable monitoring strategy for patients receiving ECMO support., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Antiphospholipid syndrome (APS) is characterized by thrombosis (which may be venous, arterial, or microvascular) and/or pregnancy morbidity in association with persistently positive antiphospholipid antibodies. Although thrombosis and pregnancy morbidity are the main clinical criteria for a diagnosis of APS in the revised Sapporo (Sydney) criteria, recently published American College of Rheumatology/European Alliance of Associations for Rheumatology classification criteria for APS have significantly refined the diagnostic algorithm to include a scoring system clustered into 6 clinical domains (macrovascular venous thromboembolism, macrovascular arterial thrombosis, microvascular thrombosis, obstetric, cardiac valve, and hematologic). Diagnosis of APS is complicated by the fact that significant heterogeneity exists in patients' clinical presentation, underlying vascular risk factors, and methods of detecting antiphospholipid antibodies. Despite the autoimmune nature of APS, anticoagulation remains the main strategy for secondary prevention of thrombosis. Furthermore, optimal antithrombotic treatment in APS patients with arterial thrombosis remains controversial due to a paucity of data from randomized controlled studies. In this paper, we present 2 cases and highlight the diagnostic and therapeutic challenges they pose and how we approach them in the light of current evidence., Competing Interests: Declaration of competing interests J.E.M. has no conflict of interest to declare. D.J.A. received funding from Bayer plc and from LEO Pharma for research outside this project., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Abstract: Thrombophilia is one of the principal features of paroxysmal nocturnal hemoglobinuria (PNH) and constitutes the main cause of disease morbidity/mortality. Anticomplement treatment has revolutionized the natural history of PNH, with control of the hemolytic process and abolition of thrombotic events (TEs). However, no guidelines exist for the management of thromboembolic complications in this setting, with type and duration of anticoagulation depending on individual practices. Besides, a scarcity of data is present on the efficacy of direct oral anticoagulants (DOACs). Herein, we accrued a large real-world cohort of patients with PNH from 4 US centers to explore features, predictors of TE, and anticoagulation strategies. Among 267 patients followed up for a total of 2043 patient-years, 56 (21%) developed TEs. These occurred at disease onset in 43% of cases, involving more frequently the venous system, typically as Budd-Chiari syndrome. Rate of TEs was halved in patients receiving complement inhibitors (21 vs 40 TEs per 1000 patient-years in untreated cases, with a 2-year cumulative incidence of thrombosis of 3.9% vs 18.3%, respectively), and varied according to PNH granulocytes and erythrocytes clone size, type, disease activity parameters, as well as number (≥2 mutations, or less) and variant allelic frequency of PIGA mutations. Anticoagulation with warfarin (39%), DOACs (37%), and low-molecular weight heparin (16%) was administered for a median of 29 months (interquartile range [IQR], 9-61.8). No thrombotic recurrence was observed in 19 patients treated with DOACs at a median observation of 17.1 months (IQR, 8.9-45) whereas 14 cases discontinued anticoagulation without TE recurrence at a median time of 51.4 months (IQR, 29.9-86.8)., (© 2024 American Society of Hematology. Published by Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.)

Opinion Statement: Cancer-associated thrombosis (CAT) has been identified as the second most prevalent cause of death after cancer itself. Moreover, the risk of thrombotic events in cancer patients increases due to anticancer drugs, such as tyrosine kinase inhibitors (TKIs). Venous thromboembolism (VTE) as well as arterial thromboembolic (ATE) events are present in CAT. Although VTE occurs more frequently, ATE events are very significant and in some cases are more dangerous than VTE. Guidelines for preventing thrombosis refer mainly VTE as well as the contribution of ATE events. Several factors are involved in thrombosis related to cancer, but the whole pathomechanism of thrombosis is not clear and may differ between patients. The activation of the coagulation system and the interaction of cancer cells with other cells including platelets, endothelial cells, monocytes, and neutrophils are promoted by a hypercoagulable state caused by cancer. We present an update on the pathomechanisms of CAT and the effect of anticancer drugs, mainly targeted therapies with a focus on TKIs. Considering the risk of bleeding associated with anticoagulation in each cancer patient, the anticoagulation strategy may involve the use of FXIa inhibitors, direct oral anticoagulants, and low-molecular-weight heparin. Further research would be valuable in developing strategies for reducing CAT., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background:  Patients with a mechanical heart valve (MHV) require oral anticoagulation. Poor anticoagulation control is thought to be associated with adverse outcomes, but data are limited., Objective:  To assess the risks of clinical outcomes in patients with a MHV and poor anticoagulation control on warfarin., Methods:  We conducted a retrospective study of consecutive patients undergoing MHV implantation at a tertiary care center (2010-2019). Primary outcome was a composite of ischemic stroke, systemic embolism, or prosthetic valve thrombosis. Major bleeding and death were key secondary outcomes. We constructed multivariable regression models to assess the association between time in therapeutic range (TTR) on warfarin beyond 90 days after surgery with outcomes., Results:  We included 671 patients with a MHV (80.6% in aortic, 14.6% in mitral position; mean age 61 years, 30.3% female). Median follow-up was 4.9 years, mean TTR was 62.5% (14.5% TTR <40%, 24.6% TTR 40-60%, and 61.0% TTR >60%). Overall rates of the primary outcome, major bleeding, and death were 0.73, 1.41, and 1.44 per 100 patient-years. Corresponding rates for patients with TTR <40% were 1.31, 2.77, and 3.22 per 100 patient-years. In adjusted analyses, every 10% decrement in TTR was associated with a 31% increase in hazard for the primary outcome (hazard ratio [HR]: 1.31, 95% confidence interval [CI]: 1.13-1.52), 34% increase in major bleeding (HR: 1.34, 95% CI: 1.17-1.52), and 32% increase in death (HR: 1.32, 95% CI: 1.11-1.57)., Conclusion:  In contemporary patients with a MHV, poor anticoagulation control on warfarin was associated with increased risks of thrombotic events, bleeding, and death., Competing Interests: I.J. has received consultancy fees from AstraZeneca, Novo Nordisk, and Boehringer Ingelheim and is supported by unrestricted research grants from Stockholm County Council, Swedish Heart-Lung Foundation, AstraZeneca, and Swedish Society of Cardiology. J.W.E. has received honoraria and/or research support from Anthos, AZ, Bayer, BI, BMS, DSI, Idorsia, Janssen, Merck, and Pfizer. M.R. has received honoraria support in the past from Bayer, BI, and Pfizer. S.S. has received research funding from Octapharma and honoraria from Alexion, Bayer, Boehringer Ingelheim, Bristol-Myers Squibb, Daiichi-Sankyo, Pfizer, and Sanofi. S.J.C. has received honoraria or research grants from Bayer, BMS, Pfizer, AstraZeneca, Javelin, Daiichi Sankyo. The remaining authors have no conflicting interests to report., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).)

Objectives: To derive systematic review-informed, modified Delphi consensus regarding the management of children on extracorporeal membrane oxygenation (ECMO) undergoing invasive procedures or interventions developed by the Pediatric Anticoagulation on ECMO CollaborativE (PEACE) Consensus Conference., Data Sources: A structured literature search was performed using PubMed, EMBASE, and Cochrane Library (CENTRAL) databases from January 1988 to May 2021., Study Selection: ECMO anticoagulation and hemostasis management in the perioperative period and during procedures., Data Extraction: Two authors reviewed all citations independently, with a third independent reviewer resolving any conflicts. Seventeen references were used for data extraction and informed recommendations. Evidence tables were constructed using a standardized data extraction form., Data Synthesis: Risk of bias was assessed using the Quality in Prognosis Studies tool. The evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation system. Forty-eight experts met over 2 years to develop evidence-based recommendations and, when evidence was lacking, expert-based consensus statements for the management of bleeding and thrombotic complications in pediatric ECMO patients. A web-based modified Delphi process was used to build consensus via the Research And Development/University of California Appropriateness Method. Consensus was defined as greater than 80% agreement. Four good practice statements, 7 recommendations, and 18 consensus statements are presented., Conclusions: Although agreement among experts was strong, important future research is required in this population for evidence-informed recommendations., Competing Interests: The Executive Committee (Drs. Alexander, Muszynski, Bembea, Cheifetz, Steiner, and Barbaro) served as arbitrators for conflict of interest management. Dr. Alexander’s institution received funding from Novartis (Prospective Trial to Assess the Angiotensin ReceptorBlocker Neprilysin Inhibitor LCZ696 Versus Angiotensin-Converting Enzyme Inhibitor for the Medical Treatment of Pediatric HF [PANORAMA-HF]). Drs. Muszynski and Alexander’s institutions received funding from the National Institutes of Health (NIH); they received support for article research from the NIH. Dr. Alexander’s institution received funding from the Extracorporeal Life Support Organization and Novartis. Dr. Emani received funding from Cheisi Pharma and Cellvie Bio. The remaining authors have disclosed that they do not have any potential conflicts of interest., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies.)

Catheter related atrial thrombus (CRAT) is a devastating complication associated with tunneled hemodialysis catheter. Abiotrophia defectiva is a rare fastidious pathogen implicated predominantly in culture negative infective endocarditis. Here we report three cases of CRAT in maintenance hemodialysis patients with variable clinical presentation caused by Abiotrophia defectiva. Video assisted thoracoscopic retrieval of atrial thrombus is a novel technique which is scarcely reported in medical literature for surgical management of large atrial thrombus. Our cases were managed by timely administration of antibiotics and anticoagulants followed by surgical retrieval of atrial thrombus with removal of tunneled dialysis catheter. This case series illustrates the importance of prompt diagnosis, appropriate anticoagulation with antibiotics, and mini-invasive surgical removal of atrial thrombus for the management of CRAT., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Objectives: To derive systematic-review informed, modified Delphi consensus regarding the management of bleeding and thrombotic complications during pediatric extracorporeal membrane oxygenation (ECMO) for the Pediatric ECMO Anticoagulation CollaborativE Consensus Conference., Data Sources: A structured literature search was performed using PubMed, EMBASE, and Cochrane Library (CENTRAL) databases from January 1988 to May 2021., Study Selection: The management of bleeding and thrombotic complications of ECMO., Data Extraction: Two authors reviewed all citations independently, with a third independent reviewer resolving conflicts. Twelve references were used for data extraction and informed recommendations. Evidence tables were constructed using a standardized data extraction form., Data Synthesis: Risk of bias was assessed using the Quality in Prognosis Studies tool. The evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation system. Forty-eight experts met over 2 years to develop evidence-based recommendations and, when evidence was lacking, expert-based consensus statements for the management of bleeding and thrombotic complications in pediatric ECMO patients. A web-based modified Delphi process was used to build consensus via the Research And Development/University of California Appropriateness Method. Consensus was defined as greater than 80% agreement. Two good practice statements, 5 weak recommendations, and 18 consensus statements are presented., Conclusions: Although bleeding and thrombotic complications during pediatric ECMO remain common, limited definitive data exist to support an evidence-based approach to treating these complications. Research is needed to improve hemostatic management of children supported with ECMO., Competing Interests: The Executive Committee (Drs. Alexander, Muszynski, Bembea, Cheifetz, Steiner, and Barbaro) served as arbitrators for conflict-of-interest management. Dr. Alexander’s institution received funding from Novartis (Prospective Trial to Assess the Angiotensin Receptor Blocker Neprilysin Inhibitor LCZ696 Versus Angiotensin-Converting Enzyme Inhibitor for the Medical Treatment of Pediatric HF [PANORAMA-HF]). Dr. Patregnani discloses consultation payments from MNK Pharmaceuticals and Pfizer. Dr. Bembea’s institution received funding from the National Institute of Neurologic Disorder and Stroke (R01NS106292), the Grifols Investigator Sponsored Research Grant, and the Department of Defense. Drs. Bembea, Alexander, and Muszynski received support for article research from the National Institutes of Health (NIH). Dr. Patregnani received funding from Mallinckrodt Pharmaceutical. Drs. Alexander and Muszynski’s institutions received funding from the NIH. Dr. Alexander’s institution received funding from the Extracorporeal Life Support Organization and Novartis. Dr. Cheifetz received funding from UptoDate. The remaining authors have disclosed that they do not have any potential conflicts of interest., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies.)

In response to growing recognition that nonadherence prevents children, adolescents, and young adults from achieving the therapeutic benefits of anticoagulant medication, the International Society on Thrombosis and Haemostasis Scientific and Standardization Committee Subcommittee on Pediatric and Neonatal Thrombosis and Hemostasis convened a working party on medication adherence. The primary aim of this article was to synthesize recommendations from the larger adherence science literature to provide guidance regarding the classification, collection, and interpretation of anticoagulation adherence data. The secondary aim of this article was to evaluate the degree to which trials published from 2013 to 2023 adhered to these guidance recommendations. As less than half of all trials reported on adherence and none included all recommended elements, the proposed International Society on Thrombosis and Haemostasis Scientific and Standardization Committee guidance has the potential to enhance the rigor and reproducibility of pediatric anticoagulant research., Competing Interests: Declaration of competing interests M.E.M., V.I., S.J., A.B., M.R., C.D.T., K.E.T., and L.L.-J. have no conflicts of interest to declare. N.A.G. receives or has recently received (past 12 months) consultancy fees from Anthos Therapeutics, Bayer, and the University of Colorado–affiliated Academic Research Organization CPC Clinical Research for roles in clinical trial planning or oversight committees (eg, advisory committee; steering committee; data and safety monitoring committee) in pharmaceutical industry–sponsored pediatric multicenter clinical trials of antithrombotic agents. He also receives consultancy fees from Novartis for data and safety monitoring committee membership in multicenter clinical trials of an immunomodulatory agent. His employer, Johns Hopkins University, receives salary support on his behalf from Boehringer-Ingelheim for data coordinating center leadership for a pediatric antithrombotic multicenter prospective observational study., (Copyright © 2024 International Society on Thrombosis and Haemostasis. Published by Elsevier Inc. All rights reserved.)

Mechanical prosthetic valve thrombosis (MPVT) is a common complication of valvular implantations. This study compared the efficacy and safety of different treatments for MPVT. A systematic search of electronic databases identified studies evaluating surgical, anticoagulant, and thrombolytic therapies. Although several studies of different types have been conducted to evaluate the efficacy of these treatment strategies the lack of randomized controlled trials has resulted in the inability to make a definitive conclusion about the pros and cons of these treatments. Recent treatments, such as slow and ultraslow infusion of thrombolytics, showed comparable efficacy and lower complication rates than traditional methods. Inadequate anticoagulant use is a major risk factor for MPVT, highlighting the importance of prevention. Treatment selection should be individualized based on patient factors and available expertise. Overall, slow and ultraslow infusion of thrombolytics may be a promising treatment option for MPVT., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Optimal first-trimester anticoagulation is still challenging in pregnant women with mechanical heart valves (MHVs) requiring high-dose warfarin. This multicenter prospective study aims to determine the optimal anticoagulation regimens for pregnant patients with MHVs., Methods: All women were allocated to one of three treatment options during first trimester including lone low-molecular-weight heparin (LMWH), combination of LMWH + 2.5 mg warfarin, and LMWH+4 mg warfarin. Primary maternal outcome included a combination of death, thromboembolism, severe bleeding, and need for treatment of mechanical valve thrombosis (MVT). Any fetal loss was determined as primary fetal outcome., Results: The study included 78 pregnancies in 65 women with MHVs. Primary maternal outcome rate was 44%, 12.5%, 3.5%, respectively. The rates of primary maternal outcome (44 vs 3.5%, P < .001), obstructive MVT (16 vs 0%, P = .04), MVT requiring treatment (28 vs 0%, P = .003), and cerebral embolism (24 vs 3.4%, P = .041) were found to be significantly higher in lone LMWH group compared to LMWH + 4 mg warfarin group. Moreover, the rates of primary maternal outcome (12.5 vs 44%, P = .015) and treatment for MHV thrombus (4.2 vs 28%, P = .049) were significantly lower in LMWH + 2.5 mg warfarin group compared to lone LMWH group. The incidences of fetal loss were 8 (32%) in the lone LMWH group, 8 (33.3%) in LMWH + 2.5 mg warfarin group, and 11 (37.9%) in LMWH + 4 mg warfarin group (P = .890 for 3-group).Warfarin related-embryopathy was not observed in any case., Conclusions: The combined anticoagulation strategy of LMWH plus low-dose warfarin during the first trimester of pregnancy may result in less maternal complications with comparable fetal outcomes in patients with MHVs., Condensed Abstract: Low-molecular-weight heparin (LMWH) is thought to be safer for the fetus, however it is suspected to be less protective for the mother. To solve this dilemma, the authors suggested a novel anticoagulation strategy in pregnant women with prosthetic valves. Seventy-eight pregnancies of 65 women (median age 32 [27-35] years) were included in the study. A combination of LMWH and a reduced dose warfarin were associated with low rates of thrombus-related complications in pregnant patients with mechanical heart valves., Competing Interests: Conflict of interest All of the authors have no conflict of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Left ventricular assist devices (LVADs) have emerged as a successful treatment option for patients with end-stage heart failure. Compared with the best medical therapy, LVADs improve survival and enhance functional capacity and quality of life. However, two major complications compromise this patient population's outcomes: thrombosis and bleeding. Despite technological innovations and better hemocompatibility, these devices alter the rheology, triggering the coagulation cascade and, therefore, require antithrombotic therapy. Anticoagulation and antiplatelet therapies represent the current standard of care. Still, inconsistency in the literature exists, especially whether antiplatelet therapy is required, whether direct oral anticoagulants can replace vitamin K antagonists and even whether phosphodiesterase type 5 inhibitors with their antithrombotic effects could be added to the regimen of anticoagulation., Methods and Analysis: We will perform a living systematic review with network meta-analysis and indirect comparison between current antithrombotic therapies, which have and have not been directly compared within clinical trials and observational studies. We will systematically search the following electronic sources: Cochrane Central Register of Controlled Trials (CENTRAL), Medical Literature Analysis and Retrieval System Online (MEDLINE) and Excerpta Medica Database (EMBASE). We will exclusively examine studies published in English from 2016 to the present. Studies conducted before 2016 will be omitted since our primary focus is evaluating continuous flow devices. Two independent reviewers will assess the articles by title, abstract and full text; any disagreement will be resolved through discussion, and a third reviewer will be involved if necessary. The Cochrane Risk of Bias tool will be used to assess the risk of bias. We will then conduct a pairwise meta-analysis; if the assumption of transitivity is satisfied, we will proceed with network meta-analysis using Bayesian methodology., Ethics and Dissemination: Formal ethical approval is not required as no primary data are collected. This systematic review and network meta-analysis will delineate the risks of stroke, thromboembolic events, pump thrombosis, gastrointestinal bleeding and mortality in patients equipped with LVADs who are subjected to various antithrombotic regimens. The findings will be disseminated via a peer-reviewed publication and presented at conference meetings. This will enhance clinical practice and guide future research on anticoagulation strategies within this distinct patient cohort., Prospero Registration Number: CRD42023465288., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Based on the results of randomized clinical trials (RCT) assessing direct oral anticoagulants (DOACs) for the treatment of patients with cancer-associated thrombosis (CAT), DOACs have been proposed as alternative to low molecular weight heparin by several international guidelines. However, the proportion of CAT patients who would have not been eligible for such trials is currently unknown. Our primary aim was to assess the proportion of patients seen in clinical practice for acute CAT who would not have been eligible for CARAVAGGIO or HOKUSAI-VTE RCT. Secondary aim was to describe patients outcomes according to eligibility. In a multicenter, observational study, all patients consecutively admitted from January 2017 to December 2019 for an acute CAT event were retrospectively analyzed. Patients were classified according to the presence or absence of non-inclusion criteria for CARAVAGGIO or HOKUSAI-VTE RCT. Event free survival during a 6-month follow-up were analyzed as secondary endpoints. Among the 302 patients (women: 53 %, mean age: 67.9 ± 13.2) analyzed, 138 (46 %) for HOKUSAI-VTE cancer and 161 (53 %) for CARAVAGGIO met one or more non-inclusion criteria. Main criteria were upper limb and unsual site thrombosis (n = 63, 18.5 %), anemia/thrombopenia (n = 43, 14.2 %), brain tumors (n = 33, 10.9 %), ECOG PS >2 (n = 28, 9.3 %), severe renal failure (n = 16, 5.3 %). At 6 months, the event-free survival rate was not statistically different between the two groups. Almost half of CAT patients would have not been able to participate to a modern DOAC RCT. Evaluation of DOACs safety and efficacy in this subset of patients deserves further research., Competing Interests: Declaration of Competing Interest No conflicts of interest., (Copyright © 2023 SPLF and Elsevier Masson SAS. All rights reserved.)

Background: The direct oral anticoagulants (DOACs) are now commonly regarded as first line anticoagulants in most cases of venous thromboembolism (VTE). However, the optimal choice of subsequent anticoagulant in instances of first line DOAC failure is unclear., Objectives: To describe and compare outcomes with second line anticoagulants used after DOAC failure., Methods: Patients seen at an urban hospital system for an episode of acute VTE initially treated with either apixaban or rivaroxaban who experienced a subsequent recurrent thrombosis while on anticoagulation (1st recurrent thrombosis) were included., Results: In total, 166 patients after apixaban or rivaroxaban failure were included. Following DOAC failure (1st recurrent thrombosis), the subsequent anticoagulant was warfarin in 60 patients (36%), dabigatran in 42 patients (25%), and enoxaparin in 64 patients (39%). Enoxaparin was preferentially prescribed in patients with a malignancy-associated etiology for 1st recurrent thrombosis (p < 0.01). The median follow-up time in our cohort was 16 months. There was no difference in 2nd recurrent thrombosis-free survival (p = 0.72) or risk for major bleeding event (p = 0.30) among patients treated with dabigatran, warfarin, or enoxaparin., Conclusions: In this retrospective analysis of patients failing first line DOAC therapy, rates of 2nd recurrent thrombosis and bleeding did not differ among subsequently chosen anticoagulants. Our study provides evidence that the optimal 2nd anticoagulant is not clear, and the choice of 2nd anticoagulant should continue to balance patient preference, cost, and provider experience., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Cancer patients are at risk of venous thromboembolism (VTE), its recurrence, but also at risk of bleeding while anticoagulated. In addition, cancer therapies have been associated to increased VTE risk. Guidelines for VTE treatment in cancer patients recommend low molecular weight heparins (LMWH) or direct oral anticoagulants (DOAC) for the initial treatment, DOAC for VTE short-term treatment, and LMWH or DOAC for VTE long-term treatment. This consensus article arises from a collaboration between different Spanish experts on cancer-associated thrombosis. It aims to reach an agreement on a practical document of recommendations for action allowing the healthcare homogenization of cancer-associated thrombosis (CAT) patients in Spain considering not only what is known about VTE management in cancer patients but also what is done in Spanish hospitals in the clinical practice. The text summarizes the current knowledge and available evidence on the subject in Spain and provides a series of practical recommendations for CAT management and treatment algorithms to help clinicians to manage CAT over time., (© 2024. The Author(s).)

Introduction: We conducted this pilot study to assess direct oral anticoagulants (DOACs) in the prevention of microvascular thrombosis., Materials and Methods: Five patients undergoing microvascular free tissue transplantation received rivaroxaban or apixaban (depending on their home medication). We compared this group to 19 patients who received enoxaparin subcutaneously. We evaluated the rate of graft loss due to microvascular thrombosis and the number of transfusions administered intra- and postoperatively., Results: There was no graft loss due to microvascular thrombosis in either of the groups. There was no significant difference in the number of intraoperative (study group mean 1.00 (SE 0.32) vs. control group mean 1.11 (SE 0.59); p = 0.876) and postoperative (study group mean 1.2 (SE 0.37) vs. control group mean 1.74 (SE 0.34); p = 0.310) red blood cell transfusions., Conclusion: Based on our results in this pilot study, DOACs can be used with microvascular flaps. Further studies with larger sample sizes should be performed to find an optimal medication regimen both for patients already taking DOACs and perhaps even for those not taking DOACs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Introduction: Recommendations about proper anticoagulation in obese patients, body mass index (BMI) > 30 kg/m2, are not yet clearly defined. Obese patients were included in randomized controlled trials comparing new anticoagulants (NOACs) with warfarin in patients with atrial fibrillation or thromboembolism., Methods: We performed a medline search entering proper criteria and finally 6 post-hoc analysis of RCTs, reporting outcome according to BMI, were included in this meta-analysis. Two major outcomes were considered end points in our meta-analysis; thrombosis, including ischemic cerebral events (transient or not) and venous thrombosis (DVD) /pulmonary embolism (PE) and bleeding, including major bleeding and clinically relevant non-major bleeding., Results: In the NOACs treated group, thrombosis occurred less frequently in obese vs non-obese patients; RR and 95 % CI 0,75 (0,58-0,97), p = 0,03, while low heterogeneity was observed (I 2= 40 %). In the warfarin treated subgroup there was statistically significant difference with less thrombotic events occurring in the obese vs non-obese patients; RR and (95 % CI) 0,80 (0,66-0,98), p = 0,03, and heterogeneity was low (I 2  = 24 %). This protective effect called the obesity paradox is limited to obese patients anticoagulated for non-valvular atrial fibrillation (NVAF); RR (95 % CI) was 0,70 (0,58-0,85) p = 0,03 and I 2  = 24 %. Bleeding events were similar under both NOACs and warfarin in obese vs non-obese analysis., Conclusions: Obese patients anticoagulated for NVAF with either standard dose of xabans or INR guided warfarin are more efficiently protected against thrombosis compared to non-obese patients., Competing Interests: Declaration of competing interest No conflict of interest to declare., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Growing evidence showing that systemic autoimmune diseases (SADs) are associated with a high risk of atrial fibrillation (AF). However, the impact of SAD on the clinical course of AF patients is largely unknown., Methods: Retrospective cohort study within a federated healthcare network (TriNetX). Using ICD codes, AF patients on anticoagulant therapy were categorized according to the presence of SAD (M32: Systemic Lupus Erythematosus (SLE); M33: Dermato-polymyositis (DMP); M34: Systemic Sclerosis (SSc); M35: Sjogren syndrome). The primary outcomes were the 5-year risks of (1) all-cause death, (2) thrombotic events (ischemic stroke, acute myocardial infarction, deep vein thrombosis, and pulmonary embolism), and (3) bleeding (intracranial (ICH) and gastrointestinal (GI)). Secondary outcomes were each component of the primary outcomes. Cox regression analysis after propensity score matching (PSM) was used to estimate hazard ratio (HR) and 95% confidence interval (95%CI)., Results: We identified 16,098 AF patients with SAD (68.2 ± 13.4 years; 71.0% female) and 828,772 AF controls (70.7 ± 12.9 years, 41.1% females). After PSM, AF patients with SAD were associated with a higher risk of all-cause death (HR 1.13, 95%CI 1.09-1.71), thrombotic events (HR 1.37, 95%CI 1.32-1.43), and hemorrhagic events (HR 1.41, 95%CI 1.33-1.50) compared to AF controls without SAD. The highest risk of all-cause death and GI bleeding was associated with SSc, while the highest risk of thrombotic events and ICH was associated with SLE., Conclusion: AF patients with SAD are associated with a high risk of all-cause death, thrombotic, and hemorrhagic events. These patients merit careful follow-up and integrated care management to improve their prognosis., (© 2024. The Author(s).)

The extensive use of therapeutic doses of heparin to prevent thrombosis in critically ill patients with COVID-19 during the pandemic has led to an increased incidence of bleeding and heparin-induced thrombocytopenia (HIT). In addition, the introduction of the AstraZeneca and Johnson&Johnson vaccines against COVID-19 into clinical practice was associated with the development of a rare but very severe, adverse thrombotic complication, vaccine-induced immune thrombotic thrombocytopenia (VITT). Thrombotic complications of VITT turned out to be similar to HIT both clinically and pathophysiologically. HIT is a potentially fatal immune-mediated adverse drug response that results in emergence of antibodies that activate platelets in the presence of heparin. HIT is characterized by a high incidence of venous and arterial thromboses, often with fatal outcomes. Currently, there are clearly defined international guidelines for the diagnosis, treatment and prevention of HIT. In case of thrombotic complications, non-heparin anticoagulants should be used.

Objectives: To assess if warfarin targeted to international normalized ratio (INR) 1.8 (range 1.5-2.0) is safe for all patients with an On-X aortic mechanical valve., Methods: This prospective, observational registry follows patients receiving warfarin targeted at an INR of 1.8 (range 1.5-2.0) plus daily aspirin (75-100 mg) after On-X aortic valve replacement. The primary end point is a composite of thromboembolism, valve thrombosis and major bleeding. Secondary end points include the individual rates of thromboembolism, valve thrombosis and major bleeding, as well as the composite in subgroups of home or clinic-monitored INR and risk categorization for thromboembolism. The control was the patient group randomized to standard-dose warfarin (INR 2.0-3.0) plus daily aspirin 81 mg from the PROACT trial., Results: A total of 510 patients were enroled at 23 centres in the UK, USA and Canada. Currently, the median follow-up duration is 3.4 years, and median achieved INR is 1.9. The primary composite end point rate in the low INR patients is 2.31% vs 5.39% (95% confidence interval 4.12-6.93%) per patient-year in the PROACT control group, constituting a 57% reduction. Results are consistent in subgroups of home or clinic-monitored, and high-risk patients, with reductions of 56%, 57% and 57%, respectively. Major and total bleeding are decreased by 85% and 73%, respectively, with similar rates of thromboembolic events. No valve thrombosis occurred., Conclusions: Interim results suggest that warfarin targeted at an INR of 1.8 (range 1.5-2.0) plus aspirin is safe and effective in patients with an On-X aortic mechanical valve with or without home INR monitoring., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery.)

Objective: Postoperative thrombotic complications represent a unique challenge in cranial neurosurgery as primary treatment involves therapeutic anticoagulation. The decision to initiate therapy and its timing is nuanced, as surgeons must balance the risk of catastrophic intracranial hemorrhage (ICH). With limited existing evidence to guide management, current practice patterns are subjective and inconsistent. The authors assessed their experience with early therapeutic anticoagulation (≤ 7 days postoperatively) initiation for thrombotic complications in neurosurgical patients undergoing cranial surgery to better understand the risks of catastrophic ICH., Methods: Adult patients treated with early therapeutic anticoagulation following cranial surgery were considered. Anticoagulation indications were restricted to thrombotic or thromboembolic complications. Records were retrospectively reviewed for demographics, surgical details, and anticoagulation therapy start. The primary outcome was the incidence of catastrophic ICH, defined as ICH resulting in reoperation or death within 30 days of anticoagulation initiation. As a secondary outcome, post-anticoagulation cranial imaging was reviewed for new or worsening acute blood products. Fisher's exact and Wilcoxon rank-sum tests were used to compare cohorts. Cumulative outcome analyses were performed for primary and secondary outcomes according to anticoagulation start time., Results: Seventy-one patients satisfied the inclusion criteria. Anticoagulation commenced on mean postoperative day (POD) 4.3 (SD 2.2). Catastrophic ICH was observed in 7 patients (9.9%) and was associated with earlier anticoagulation initiation (p = 0.02). Of patients with catastrophic ICH, 6 (85.7%) had intra-axial exploration during their index surgery. Patients with intra-axial exploration were more likely to experience a catastrophic ICH postoperatively compared to those with extra-axial exploration alone (OR 8.5, p = 0.04). Of the 58 patients with postoperative imaging, 15 (25.9%) experienced new or worsening blood products. Catastrophic ICH was 9 times more likely with anticoagulation initiation within 48 hours of surgery (OR 8.9, p = 0.01). The cumulative catastrophic ICH risk decreased with delay in initiation of anticoagulation, from 21.1% on POD 2 to 9.9% on POD 7. Concurrent antiplatelet medication was not associated with either outcome measure., Conclusions: The incidence of catastrophic ICH was significantly increased when anticoagulation was initiated within 48 hours of cranial surgery. Patients undergoing intra-axial exploration during their index surgery were at higher risk of a catastrophic ICH.

Development of thrombosis is closely associated with poor prognosis in cancer patients. Cancer patients often fulfill Virchow's triad of hyper-coagulable state, vascular endothelial injury, and venous stasis. Cancer cells aberrantly express a variety of procoagulant factors, including tissue factor and podoplanin. Chemotherapeutic agents and radiation cause vascular endothelial injury, and reduced daily activity and bed rest for chemotherapy lead to venous stasis. Due to these factors, cancer patients are at high risk of developing thrombosis. Cancer patients are also at high risk of bleeding when they have disseminated intravascular coagulation and/or chemotherapy-induced thrombocytopenia as complications. International societies, such as the American Society of Clinical Oncology and the International Initiative on Thrombosis and Cancer (ITAC), have published clinical guidelines to help physicians better manage cancer-associated thrombosis (CAT). These guidelines recommend use of low molecular weight heparin or direct oral anticoagulants for the prevention of CAT, but unfortunately use of these drugs is not approved in Japan. This gap between Japan and other countries needs to be closed., (© 2024. Japanese Society of Hematology.)

Cancer-associated thrombosis (CAT) is an important prognostic factor for an increasing number of cancer patients. Understanding of CAT among cancer care providers has grown in recent years, and guidelines for the prevention and treatment of CAT have been published in Japan and around the world. In this article, we introduce these major guidelines and discuss differences we identified between the Japanese guidelines and those of other countries, with a focus on problems and issues. Insurance coverage of low-molecular-weight heparin and indications for primary prevention with direct oral anticoagulants in particular require urgent consideration., (© 2024. Japanese Society of Hematology.)

Thrombotic antiphospholipid syndrome (TAPS) is characterized by thrombosis and persistently positive tests for antiphospholipid antibodies or lupus anticoagulant (LAC). Triple-positive APS has the highest risk of recurrent thrombosis, but no studies have focused on recurrent thrombosis in patients with single-positive TAPS. We conducted a retrospective cohort study of patients with single-positive TAPS diagnosed at Lifespan Health System, Rhode Island, to determine the rates and risk factors for recurrent thrombosis. Between January 2001 and April 2022, 128 patients were assessed who had single-positive APS (LAC = 98, aCL = 21, aβ2GPI = 9) and who had been followed for a total of 1453.8 patient-years (median follow-up 3.04 years). The initial antithrombotic regimen was warfarin in 44 %, a direct oral anticoagulant (DOAC) in 34 %, enoxaparin in 2 %, and no antithrombotic therapy or antiplatelet therapy only in 20 %. Recurrent thrombosis occurred in 16 (12.5 %) with a recurrent thrombosis rate of 3.08 per 100 patient-years. Systemic lupus erythematosus was the only variable significantly associated with recurrent thrombosis in a model adjusted for age, sex, body mass index, and type of positive APS test. All 16 patients with recurrent thrombosis were initially treated with warfarin, and, at the time of recurrent thrombosis, 13 patients remained on warfarin and three were off anticoagulation. In conclusion, the recurrent thrombosis rate in single-positive APS is low, and not all patients with a single-positive test may need indefinite anticoagulation with warfarin. Larger prospective studies are required to confirm this finding and establish optimal anticoagulation regimens for low-risk TAPS., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: There were no conflicts of interest for Dr. Bakow and Lisa Yanek. Dr. Chaturvedi has received honoraria for consulting or advisory board participation from Alexion, Sanofi Genzyme, Sobi, Takeda, and UCB pharmaceuticals. Her institution has received research funding on her behalf from Takeda. She has also received honoraria/royalties from UpToDate.com and Dynamed,com. In the last 36 months, Dr. Crowther has received Personal Funding or has sat on Advisory Boards for Astra Zeneca, Hemostasis Reference Laboratories, Syneos Health, and Eversana. He has prepared educational materials and/or presented talks for Bayer, Pfizer, and CSL Behring. He has participated in various medicolegal activities relating to thrombosis, anticoagulant drugs, or other aspects of hematological practice. He has also worked with multiple for-profit and not-for-profit entities such as Up To Date and medical communication companies. He holds the Leo Pharma Chair in Thromboembolism, endowed at McMaster University., (Copyright © 2024 Elsevier Ltd. All rights reserved.)